Struct qt_core::QTemporaryFile

#[repr(C)]
pub struct QTemporaryFile { /* private fields */ }

The QTemporaryFile class is an I/O device that operates on temporary files.

C++ class: QTemporaryFile.

C++ documentation:

The QTemporaryFile class is an I/O device that operates on temporary files.

QTemporaryFile is used to create unique temporary files safely. The file itself is created by calling open(). The name of the temporary file is guaranteed to be unique (i.e., you are guaranteed to not overwrite an existing file), and the file will subsequently be removed upon destruction of the QTemporaryFile object. This is an important technique that avoids data corruption for applications that store data in temporary files. The file name is either auto-generated, or created based on a template, which is passed to QTemporaryFile's constructor.

Example:

      // Within a function/method…
      QTemporaryFile file;
      if (file.open()) {
          // file.fileName() returns the unique file name
      }
      // The QTemporaryFile destructor removes the temporary file
      // as it goes out of scope.

Reopening a QTemporaryFile after calling close() is safe. For as long as the QTemporaryFile object itself is not destroyed, the unique temporary file will exist and be kept open internally by QTemporaryFile.

The file name of the temporary file can be found by calling fileName(). Note that this is only defined after the file is first opened; the function returns an empty string before this.

A temporary file will have some static part of the name and some part that is calculated to be unique. The default filename will be determined from QCoreApplication::applicationName() (otherwise qt_temp) and will be placed into the temporary path as returned by QDir::tempPath(). If you specify your own filename, a relative file path will not be placed in the temporary directory by default, but be relative to the current working directory.

Specified filenames can contain the following template XXXXXX (six upper case "X" characters), which will be replaced by the auto-generated portion of the filename. Note that the template is case sensitive. If the template is not present in the filename, QTemporaryFile appends the generated part to the filename given.

Implementations

impl QTemporaryFile

pub unsafe fn auto_remove(&self) -> bool

Returns true if the QTemporaryFile is in auto remove mode. Auto-remove mode will automatically delete the filename from disk upon destruction. This makes it very easy to create your QTemporaryFile object on the stack, fill it with data, read from it, and finally on function return it will automatically clean up after itself.

Calls C++ function: bool QTemporaryFile::autoRemove() const.

C++ documentation:

Returns true if the QTemporaryFile is in auto remove mode. Auto-remove mode will automatically delete the filename from disk upon destruction. This makes it very easy to create your QTemporaryFile object on the stack, fill it with data, read from it, and finally on function return it will automatically clean up after itself.

Auto-remove is on by default.

See also setAutoRemove() and remove().

pub unsafe fn create_local_file_q_string( file_name: impl CastInto<Ref<QString>> ) -> QPtr<QTemporaryFile>

Use QTemporaryFile::createNativeFile(QFile &file) instead.

Calls C++ function: static QTemporaryFile* QTemporaryFile::createLocalFile(const QString& fileName).

Warning: no exact match found in C++ documentation. Below is the C++ documentation for static QTemporaryFile *QTemporaryFile::createLocalFile(QFile &file):

Use QTemporaryFile::createNativeFile(QFile &file) instead.

pub unsafe fn create_local_file_q_file( file: impl CastInto<Ref<QFile>> ) -> QPtr<QTemporaryFile>

Use QTemporaryFile::createNativeFile(QFile &file) instead.

Calls C++ function: static QTemporaryFile* QTemporaryFile::createLocalFile(QFile& file).

C++ documentation:

Use QTemporaryFile::createNativeFile(QFile &file) instead.

pub unsafe fn create_native_file_q_string( file_name: impl CastInto<Ref<QString>> ) -> QPtr<QTemporaryFile>

This is an overloaded function.

Calls C++ function: static QTemporaryFile* QTemporaryFile::createNativeFile(const QString& fileName).

C++ documentation:

This is an overloaded function.

Works on the given fileName rather than an existing QFile object.

pub unsafe fn create_native_file_q_file( file: impl CastInto<Ref<QFile>> ) -> QPtr<QTemporaryFile>

If file is not already a native file, then a QTemporaryFile is created in QDir::tempPath(), the contents of file is copied into it, and a pointer to the temporary file is returned. Does nothing and returns 0 if file is already a native file.

Calls C++ function: static QTemporaryFile* QTemporaryFile::createNativeFile(QFile& file).

C++ documentation:

If file is not already a native file, then a QTemporaryFile is created in QDir::tempPath(), the contents of file is copied into it, and a pointer to the temporary file is returned. Does nothing and returns 0 if file is already a native file.

For example:

QFile f(“:/resources/file.txt”);
QTemporaryFile::createNativeFile(f); // Returns a pointer to a temporary file
QFile f(“/users/qt/file.txt”);
QTemporaryFile::createNativeFile(f); // Returns 0

See also QFileInfo::isNativePath().

pub unsafe fn file_name(&self) -> CppBox<QString>

Reimplemented from QFileDevice::fileName().

Calls C++ function: virtual QString QTemporaryFile::fileName() const.

C++ documentation:

Reimplemented from QFileDevice::fileName().

Returns the complete unique filename backing the QTemporaryFile object. This string is null before the QTemporaryFile is opened, afterwards it will contain the fileTemplate() plus additional characters to make it unique.

See also fileTemplate().

pub unsafe fn file_template(&self) -> CppBox<QString>

Returns the set file template. The default file template will be called qcoreappname.XXXXXX and be placed in QDir::tempPath().

Calls C++ function: QString QTemporaryFile::fileTemplate() const.

C++ documentation:

Returns the set file template. The default file template will be called qcoreappname.XXXXXX and be placed in QDir::tempPath().

See also setFileTemplate().

pub unsafe fn meta_object(&self) -> Ptr<QMetaObject>

Calls C++ function: virtual const QMetaObject* QTemporaryFile::metaObject() const.

pub unsafe fn new() -> QBox<QTemporaryFile>

Constructs a QTemporaryFile using as file template the application name returned by QCoreApplication::applicationName() (otherwise qt_temp) followed by ".XXXXXX". The file is stored in the system's temporary directory, QDir::tempPath().

Calls C++ function: [constructor] void QTemporaryFile::QTemporaryFile().

C++ documentation:

Constructs a QTemporaryFile using as file template the application name returned by QCoreApplication::applicationName() (otherwise qt_temp) followed by “.XXXXXX”. The file is stored in the system’s temporary directory, QDir::tempPath().

See also setFileTemplate() and QDir::tempPath().

pub unsafe fn from_q_string( template_name: impl CastInto<Ref<QString>> ) -> QBox<QTemporaryFile>

Constructs a QTemporaryFile with a template filename of templateName. Upon opening the temporary file this will be used to create a unique filename.

Calls C++ function: [constructor] void QTemporaryFile::QTemporaryFile(const QString& templateName).

C++ documentation:

Constructs a QTemporaryFile with a template filename of templateName. Upon opening the temporary file this will be used to create a unique filename.

If the templateName does not contain XXXXXX it will automatically be appended and used as the dynamic portion of the filename.

If templateName is a relative path, the path will be relative to the current working directory. You can use QDir::tempPath() to construct templateName if you want use the system's temporary directory.

See also open() and fileTemplate().

pub unsafe fn from_q_object( parent: impl CastInto<Ptr<QObject>> ) -> QBox<QTemporaryFile>

Constructs a QTemporaryFile (with the given parent) using as file template the application name returned by QCoreApplication::applicationName() (otherwise qt_temp) followed by ".XXXXXX". The file is stored in the system's temporary directory, QDir::tempPath().

Calls C++ function: [constructor] void QTemporaryFile::QTemporaryFile(QObject* parent).

C++ documentation:

Constructs a QTemporaryFile (with the given parent) using as file template the application name returned by QCoreApplication::applicationName() (otherwise qt_temp) followed by “.XXXXXX”. The file is stored in the system’s temporary directory, QDir::tempPath().

See also setFileTemplate().

pub unsafe fn from_q_string_q_object( template_name: impl CastInto<Ref<QString>>, parent: impl CastInto<Ptr<QObject>> ) -> QBox<QTemporaryFile>

Constructs a QTemporaryFile with a template filename of templateName and the specified parent. Upon opening the temporary file this will be used to create a unique filename.

Calls C++ function: [constructor] void QTemporaryFile::QTemporaryFile(const QString& templateName, QObject* parent).

C++ documentation:

Constructs a QTemporaryFile with a template filename of templateName and the specified parent. Upon opening the temporary file this will be used to create a unique filename.

If the templateName does not contain XXXXXX it will automatically be appended and used as the dynamic portion of the filename.

If templateName is a relative path, the path will be relative to the current working directory. You can use QDir::tempPath() to construct templateName if you want use the system's temporary directory.

See also open() and fileTemplate().

pub unsafe fn open(&self) -> bool

A QTemporaryFile will always be opened in QIODevice::ReadWrite mode, this allows easy access to the data in the file. This function will return true upon success and will set the fileName() to the unique filename used.

Calls C++ function: bool QTemporaryFile::open().

C++ documentation:

A QTemporaryFile will always be opened in QIODevice::ReadWrite mode, this allows easy access to the data in the file. This function will return true upon success and will set the fileName() to the unique filename used.

See also fileName().

pub unsafe fn qt_metacall( &self, arg1: Call, arg2: c_int, arg3: *mut *mut c_void ) -> c_int

Calls C++ function: virtual int QTemporaryFile::qt_metacall(QMetaObject::Call arg1, int arg2, void** arg3).

pub unsafe fn qt_metacast(&self, arg1: *const c_char) -> *mut c_void

Calls C++ function: virtual void* QTemporaryFile::qt_metacast(const char* arg1).

pub unsafe fn rename(&self, new_name: impl CastInto<Ref<QString>>) -> bool

Calls C++ function: bool QTemporaryFile::rename(const QString& newName).

pub unsafe fn set_auto_remove(&self, b: bool)

Sets the QTemporaryFile into auto-remove mode if b is true.

Calls C++ function: void QTemporaryFile::setAutoRemove(bool b).

C++ documentation:

Sets the QTemporaryFile into auto-remove mode if b is true.

Auto-remove is on by default.

See also autoRemove() and remove().

pub unsafe fn set_file_template(&self, name: impl CastInto<Ref<QString>>)

Sets the static portion of the file name to name. If the file template contains XXXXXX that will automatically be replaced with the unique part of the filename, otherwise a filename will be determined automatically based on the static portion specified.

Calls C++ function: void QTemporaryFile::setFileTemplate(const QString& name).

C++ documentation:

Sets the static portion of the file name to name. If the file template contains XXXXXX that will automatically be replaced with the unique part of the filename, otherwise a filename will be determined automatically based on the static portion specified.

If name contains a relative file path, the path will be relative to the current working directory. You can use QDir::tempPath() to construct name if you want use the system's temporary directory.

See also fileTemplate().

pub unsafe fn static_meta_object() -> Ref<QMetaObject>

Returns a reference to the staticMetaObject field.

pub unsafe fn tr( s: *const c_char, c: *const c_char, n: c_int ) -> CppBox<QString>

Calls C++ function: static QString QTemporaryFile::tr(const char* s, const char* c, int n).

pub unsafe fn tr_utf8( s: *const c_char, c: *const c_char, n: c_int ) -> CppBox<QString>

Calls C++ function: static QString QTemporaryFile::trUtf8(const char* s, const char* c, int n).

Methods from Deref<Target = QFile>

pub unsafe fn copy_mut(&self, new_name: impl CastInto<Ref<QString>>) -> bool

Copies the file currently specified by fileName() to a file called newName. Returns true if successful; otherwise returns false.

Calls C++ function: bool QFile::copy(const QString& newName).

C++ documentation:

Copies the file currently specified by fileName() to a file called newName. Returns true if successful; otherwise returns false.

Note that if a file with the name newName already exists, copy() returns false (i.e. QFile will not overwrite it).

The source file is closed before it is copied.

See also setFileName().

pub unsafe fn exists_0a(&self) -> bool

This is an overloaded function.

Calls C++ function: bool QFile::exists() const.

C++ documentation:

This is an overloaded function.

Returns true if the file specified by fileName() exists; otherwise returns false.

See also fileName() and setFileName().

pub unsafe fn file_name(&self) -> CppBox<QString>

Reimplemented from QFileDevice::fileName().

Calls C++ function: virtual QString QFile::fileName() const.

C++ documentation:

Reimplemented from QFileDevice::fileName().

Returns the name set by setFileName() or to the QFile constructors.

See also setFileName() and QFileInfo::fileName().

pub unsafe fn link_mut(&self, new_name: impl CastInto<Ref<QString>>) -> bool

Creates a link named linkName that points to the file currently specified by fileName(). What a link is depends on the underlying filesystem (be it a shortcut on Windows or a symbolic link on Unix). Returns true if successful; otherwise returns false.

Calls C++ function: bool QFile::link(const QString& newName).

C++ documentation:

Creates a link named linkName that points to the file currently specified by fileName(). What a link is depends on the underlying filesystem (be it a shortcut on Windows or a symbolic link on Unix). Returns true if successful; otherwise returns false.

This function will not overwrite an already existing entity in the file system; in this case, link() will return false and set error() to return RenameError.

Note: To create a valid link on Windows, linkName must have a .lnk file extension.

See also setFileName().

pub unsafe fn meta_object(&self) -> Ptr<QMetaObject>

Calls C++ function: virtual const QMetaObject* QFile::metaObject() const.

pub unsafe fn open_1a(&self, flags: QFlags<OpenModeFlag>) -> bool

Reimplemented from QIODevice::open().

Calls C++ function: virtual bool QFile::open(QFlags<QIODevice::OpenModeFlag> flags).

C++ documentation:

Reimplemented from QIODevice::open().

Opens the file using OpenMode mode, returning true if successful; otherwise false.

The mode must be QIODevice::ReadOnly, QIODevice::WriteOnly, or QIODevice::ReadWrite. It may also have additional flags, such as QIODevice::Text and QIODevice::Unbuffered.

Note: In WriteOnly or ReadWrite mode, if the relevant file does not already exist, this function will try to create a new file before opening it.

See also QIODevice::OpenMode and setFileName().

pub unsafe fn open_3a( &self, fd: c_int, io_flags: QFlags<OpenModeFlag>, handle_flags: QFlags<FileHandleFlag> ) -> bool

This is an overloaded function.

Calls C++ function: bool QFile::open(int fd, QFlags<QIODevice::OpenModeFlag> ioFlags, QFlags<QFileDevice::FileHandleFlag> handleFlags = …).

C++ documentation:

This is an overloaded function.

Opens the existing file descriptor fd in the given mode. handleFlags may be used to specify additional options. Returns true if successful; otherwise returns false.

When a QFile is opened using this function, behaviour of close() is controlled by the AutoCloseHandle flag. If AutoCloseHandle is specified, and this function succeeds, then calling close() closes the adopted handle. Otherwise, close() does not actually close the file, but only flushes it.

The QFile that is opened using this function is automatically set to be in raw mode; this means that the file input/output functions are slow. If you run into performance issues, you should try to use one of the other open functions.

Warning: If fd is not a regular file, e.g, it is 0 (stdin), 1 (stdout), or 2 (stderr), you may not be able to seek(). In those cases, size() returns 0. See QIODevice::isSequential() for more information.

Warning: Since this function opens the file without specifying the file name, you cannot use this QFile with a QFileInfo.

See also close().

pub unsafe fn open_2a(&self, fd: c_int, io_flags: QFlags<OpenModeFlag>) -> bool

This is an overloaded function.

Calls C++ function: bool QFile::open(int fd, QFlags<QIODevice::OpenModeFlag> ioFlags).

C++ documentation:

This is an overloaded function.

Opens the existing file descriptor fd in the given mode. handleFlags may be used to specify additional options. Returns true if successful; otherwise returns false.

When a QFile is opened using this function, behaviour of close() is controlled by the AutoCloseHandle flag. If AutoCloseHandle is specified, and this function succeeds, then calling close() closes the adopted handle. Otherwise, close() does not actually close the file, but only flushes it.

The QFile that is opened using this function is automatically set to be in raw mode; this means that the file input/output functions are slow. If you run into performance issues, you should try to use one of the other open functions.

Warning: If fd is not a regular file, e.g, it is 0 (stdin), 1 (stdout), or 2 (stderr), you may not be able to seek(). In those cases, size() returns 0. See QIODevice::isSequential() for more information.

Warning: Since this function opens the file without specifying the file name, you cannot use this QFile with a QFileInfo.

See also close().

pub unsafe fn permissions_0a(&self) -> QFlags<Permission>

Reimplemented from QFileDevice::permissions().

Calls C++ function: virtual QFlags<QFileDevice::Permission> QFile::permissions() const.

C++ documentation:

Reimplemented from QFileDevice::permissions().

See also setPermissions().

pub unsafe fn qt_metacall( &self, arg1: Call, arg2: c_int, arg3: *mut *mut c_void ) -> c_int

Calls C++ function: virtual int QFile::qt_metacall(QMetaObject::Call arg1, int arg2, void** arg3).

pub unsafe fn qt_metacast(&self, arg1: *const c_char) -> *mut c_void

Calls C++ function: virtual void* QFile::qt_metacast(const char* arg1).

pub unsafe fn read_link_0a(&self) -> CppBox<QString>

Use symLinkTarget() instead.

Calls C++ function: QString QFile::readLink() const.

C++ documentation:

Use symLinkTarget() instead.

pub unsafe fn remove_mut(&self) -> bool

Removes the file specified by fileName(). Returns true if successful; otherwise returns false.

Calls C++ function: bool QFile::remove().

C++ documentation:

Removes the file specified by fileName(). Returns true if successful; otherwise returns false.

The file is closed before it is removed.

See also setFileName().

pub unsafe fn rename_mut(&self, new_name: impl CastInto<Ref<QString>>) -> bool

Renames the file currently specified by fileName() to newName. Returns true if successful; otherwise returns false.

Calls C++ function: bool QFile::rename(const QString& newName).

C++ documentation:

Renames the file currently specified by fileName() to newName. Returns true if successful; otherwise returns false.

If a file with the name newName already exists, rename() returns false (i.e., QFile will not overwrite it).

The file is closed before it is renamed.

If the rename operation fails, Qt will attempt to copy this file's contents to newName, and then remove this file, keeping only newName. If that copy operation fails or this file can't be removed, the destination file newName is removed to restore the old state.

See also setFileName().

pub unsafe fn resize_mut(&self, sz: i64) -> bool

Reimplemented from QFileDevice::resize().

Calls C++ function: virtual bool QFile::resize(qint64 sz).

C++ documentation:

Reimplemented from QFileDevice::resize().

pub unsafe fn set_file_name(&self, name: impl CastInto<Ref<QString>>)

Sets the name of the file. The name can have no path, a relative path, or an absolute path.

Calls C++ function: void QFile::setFileName(const QString& name).

C++ documentation:

Sets the name of the file. The name can have no path, a relative path, or an absolute path.

Do not call this function if the file has already been opened.

If the file name has no path or a relative path, the path used will be the application's current directory path at the time of the open() call.

Example:

QFile file;
QDir::setCurrent(“/tmp”);
file.setFileName(“readme.txt”);
QDir::setCurrent(“/home”);
file.open(QIODevice::ReadOnly);      // opens “/home/readme.txt” under Unix

Note that the directory separator "/" works for all operating systems supported by Qt.

See also fileName(), QFileInfo, and QDir.

pub unsafe fn set_permissions_mut( &self, permission_spec: QFlags<Permission> ) -> bool

Reimplemented from QFileDevice::setPermissions().

Calls C++ function: virtual bool QFile::setPermissions(QFlags<QFileDevice::Permission> permissionSpec).

C++ documentation:

Reimplemented from QFileDevice::setPermissions().

Sets the permissions for the file to the permissions specified. Returns true if successful, or false if the permissions cannot be modified.

Warning: This function does not manipulate ACLs, which may limit its effectiveness.

See also permissions() and setFileName().

pub unsafe fn size(&self) -> i64

Reimplemented from QIODevice::size().

Calls C++ function: virtual qint64 QFile::size() const.

C++ documentation:

Reimplemented from QIODevice::size().

pub unsafe fn sym_link_target_0a(&self) -> CppBox<QString>

This is an overloaded function.

Calls C++ function: QString QFile::symLinkTarget() const.

C++ documentation:

This is an overloaded function.

Returns the absolute path of the file or directory a symlink (or shortcut on Windows) points to, or a an empty string if the object isn't a symbolic link.

This name may not represent an existing file; it is only a string. QFile::exists() returns true if the symlink points to an existing file.

This function was introduced in Qt 4.2.

See also fileName() and setFileName().

Methods from Deref<Target = QFileDevice>

pub unsafe fn at_end(&self) -> bool

Reimplemented from QIODevice::atEnd().

Calls C++ function: virtual bool QFileDevice::atEnd() const.

C++ documentation:

Reimplemented from QIODevice::atEnd().

Returns true if the end of the file has been reached; otherwise returns false.

For regular empty files on Unix (e.g. those in /proc), this function returns true, since the file system reports that the size of such a file is 0. Therefore, you should not depend on atEnd() when reading data from such a file, but rather call read() until no more data can be read.

pub unsafe fn close(&self)

Reimplemented from QIODevice::close().

Calls C++ function: virtual void QFileDevice::close().

C++ documentation:

Reimplemented from QIODevice::close().

Calls QFileDevice::flush() and closes the file. Errors from flush are ignored.

See also QIODevice::close().

pub unsafe fn error(&self) -> FileError

Returns the file error status.

Calls C++ function: QFileDevice::FileError QFileDevice::error() const.

C++ documentation:

Returns the file error status.

The I/O device status returns an error code. For example, if open() returns false, or a read/write operation returns -1, this function can be called to find out the reason why the operation failed.

See also unsetError().

pub unsafe fn file_name(&self) -> CppBox<QString>

Returns the name of the file. The default implementation in QFileDevice returns a null string.

Calls C++ function: virtual QString QFileDevice::fileName() const.

C++ documentation:

Returns the name of the file. The default implementation in QFileDevice returns a null string.

pub unsafe fn file_time(&self, time: FileTime) -> CppBox<QDateTime>

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Returns the file time specified by time. If the time cannot be determined return QDateTime() (an invalid date time).

Calls C++ function: QDateTime QFileDevice::fileTime(QFileDevice::FileTime time) const.

C++ documentation:

Returns the file time specified by time. If the time cannot be determined return QDateTime() (an invalid date time).

This function was introduced in Qt 5.10.

See also setFileTime(), FileTime, and QDateTime::isValid().

pub unsafe fn flush(&self) -> bool

Flushes any buffered data to the file. Returns true if successful; otherwise returns false.

Calls C++ function: bool QFileDevice::flush().

C++ documentation:

Flushes any buffered data to the file. Returns true if successful; otherwise returns false.

pub unsafe fn handle(&self) -> c_int

Returns the file handle of the file.

Calls C++ function: int QFileDevice::handle() const.

C++ documentation:

Returns the file handle of the file.

This is a small positive integer, suitable for use with C library functions such as fdopen() and fcntl(). On systems that use file descriptors for sockets (i.e. Unix systems, but not Windows) the handle can be used with QSocketNotifier as well.

If the file is not open, or there is an error, handle() returns -1.

See also QSocketNotifier.

pub unsafe fn is_sequential(&self) -> bool

Reimplemented from QIODevice::isSequential().

Calls C++ function: virtual bool QFileDevice::isSequential() const.

C++ documentation:

Reimplemented from QIODevice::isSequential().

Returns true if the file can only be manipulated sequentially; otherwise returns false.

Most files support random-access, but some special files may not.

See also QIODevice::isSequential().

pub unsafe fn map_3a( &self, offset: i64, size: i64, flags: MemoryMapFlags ) -> *mut c_uchar

Maps size bytes of the file into memory starting at offset. A file should be open for a map to succeed but the file does not need to stay open after the memory has been mapped. When the QFile is destroyed or a new file is opened with this object, any maps that have not been unmapped will automatically be unmapped.

Calls C++ function: unsigned char* QFileDevice::map(qint64 offset, qint64 size, QFileDevice::MemoryMapFlags flags = …).

C++ documentation:

Maps size bytes of the file into memory starting at offset. A file should be open for a map to succeed but the file does not need to stay open after the memory has been mapped. When the QFile is destroyed or a new file is opened with this object, any maps that have not been unmapped will automatically be unmapped.

The mapping will have the same open mode as the file (read and/or write), except when using MapPrivateOption, in which case it is always possible to write to the mapped memory.

Any mapping options can be passed through flags.

Returns a pointer to the memory or 0 if there is an error.

See also unmap().

pub unsafe fn map_2a(&self, offset: i64, size: i64) -> *mut c_uchar

Maps size bytes of the file into memory starting at offset. A file should be open for a map to succeed but the file does not need to stay open after the memory has been mapped. When the QFile is destroyed or a new file is opened with this object, any maps that have not been unmapped will automatically be unmapped.

Calls C++ function: unsigned char* QFileDevice::map(qint64 offset, qint64 size).

C++ documentation:

Maps size bytes of the file into memory starting at offset. A file should be open for a map to succeed but the file does not need to stay open after the memory has been mapped. When the QFile is destroyed or a new file is opened with this object, any maps that have not been unmapped will automatically be unmapped.

The mapping will have the same open mode as the file (read and/or write), except when using MapPrivateOption, in which case it is always possible to write to the mapped memory.

Any mapping options can be passed through flags.

Returns a pointer to the memory or 0 if there is an error.

See also unmap().

pub unsafe fn meta_object(&self) -> Ptr<QMetaObject>

Calls C++ function: virtual const QMetaObject* QFileDevice::metaObject() const.

pub unsafe fn permissions(&self) -> QFlags<Permission>

Returns the complete OR-ed together combination of QFile::Permission for the file.

Calls C++ function: virtual QFlags<QFileDevice::Permission> QFileDevice::permissions() const.

C++ documentation:

Returns the complete OR-ed together combination of QFile::Permission for the file.

See also setPermissions().

pub unsafe fn pos(&self) -> i64

Reimplemented from QIODevice::pos().

Calls C++ function: virtual qint64 QFileDevice::pos() const.

C++ documentation:

Reimplemented from QIODevice::pos().

pub unsafe fn qt_metacall( &self, arg1: Call, arg2: c_int, arg3: *mut *mut c_void ) -> c_int

Calls C++ function: virtual int QFileDevice::qt_metacall(QMetaObject::Call arg1, int arg2, void** arg3).

pub unsafe fn qt_metacast(&self, arg1: *const c_char) -> *mut c_void

Calls C++ function: virtual void* QFileDevice::qt_metacast(const char* arg1).

pub unsafe fn resize(&self, sz: i64) -> bool

Sets the file size (in bytes) sz. Returns true if the resize succeeds; false otherwise. If sz is larger than the file currently is, the new bytes will be set to 0; if sz is smaller, the file is simply truncated.

Calls C++ function: virtual bool QFileDevice::resize(qint64 sz).

C++ documentation:

Sets the file size (in bytes) sz. Returns true if the resize succeeds; false otherwise. If sz is larger than the file currently is, the new bytes will be set to 0; if sz is smaller, the file is simply truncated.

Warning: This function can fail if the file doesn't exist.

See also size().

pub unsafe fn seek(&self, offset: i64) -> bool

Reimplemented from QIODevice::seek().

Calls C++ function: virtual bool QFileDevice::seek(qint64 offset).

C++ documentation:

Reimplemented from QIODevice::seek().

For random-access devices, this function sets the current position to pos, returning true on success, or false if an error occurred. For sequential devices, the default behavior is to do nothing and return false.

Seeking beyond the end of a file: If the position is beyond the end of a file, then seek() will not immediately extend the file. If a write is performed at this position, then the file will be extended. The content of the file between the previous end of file and the newly written data is UNDEFINED and varies between platforms and file systems.

pub unsafe fn set_file_time( &self, new_date: impl CastInto<Ref<QDateTime>>, file_time: FileTime ) -> bool

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Sets the file time specified by fileTime to newDate, returning true if successful; otherwise returns false.

Calls C++ function: bool QFileDevice::setFileTime(const QDateTime& newDate, QFileDevice::FileTime fileTime).

C++ documentation:

Sets the file time specified by fileTime to newDate, returning true if successful; otherwise returns false.

Note: The file must be open to use this function.

This function was introduced in Qt 5.10.

See also fileTime() and FileTime.

pub unsafe fn set_permissions( &self, permission_spec: QFlags<Permission> ) -> bool

Sets the permissions for the file to the permissions specified. Returns true if successful, or false if the permissions cannot be modified.

Calls C++ function: virtual bool QFileDevice::setPermissions(QFlags<QFileDevice::Permission> permissionSpec).

C++ documentation:

Sets the permissions for the file to the permissions specified. Returns true if successful, or false if the permissions cannot be modified.

Warning: This function does not manipulate ACLs, which may limit its effectiveness.

See also permissions().

pub unsafe fn size(&self) -> i64

Reimplemented from QIODevice::size().

Calls C++ function: virtual qint64 QFileDevice::size() const.

C++ documentation:

Reimplemented from QIODevice::size().

Returns the size of the file.

For regular empty files on Unix (e.g. those in /proc), this function returns 0; the contents of such a file are generated on demand in response to you calling read().

pub unsafe fn unmap(&self, address: *mut c_uchar) -> bool

Unmaps the memory address.

Calls C++ function: bool QFileDevice::unmap(unsigned char* address).

C++ documentation:

Unmaps the memory address.

Returns true if the unmap succeeds; false otherwise.

See also map().

pub unsafe fn unset_error(&self)

Sets the file's error to QFileDevice::NoError.

Calls C++ function: void QFileDevice::unsetError().

C++ documentation:

Sets the file’s error to QFileDevice::NoError.

See also error().

Methods from Deref<Target = QIODevice>

pub fn ready_read(&self) -> Signal<()>

This signal is emitted once every time new data is available for reading from the device's current read channel. It will only be emitted again once new data is available, such as when a new payload of network data has arrived on your network socket, or when a new block of data has been appended to your device.

Returns a built-in Qt signal QIODevice::readyRead that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted once every time new data is available for reading from the device’s current read channel. It will only be emitted again once new data is available, such as when a new payload of network data has arrived on your network socket, or when a new block of data has been appended to your device.

readyRead() is not emitted recursively; if you reenter the event loop or call waitForReadyRead() inside a slot connected to the readyRead() signal, the signal will not be reemitted (although waitForReadyRead() may still return true).

Note for developers implementing classes derived from QIODevice: you should always emit readyRead() when new data has arrived (do not emit it only because there's data still to be read in your buffers). Do not emit readyRead() in other conditions.

See also bytesWritten().

pub fn channel_ready_read(&self) -> Signal<(c_int,)>

This signal is emitted when new data is available for reading from the device. The channel argument is set to the index of the read channel on which the data has arrived. Unlike readyRead(), it is emitted regardless of the current read channel.

Returns a built-in Qt signal QIODevice::channelReadyRead that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted when new data is available for reading from the device. The channel argument is set to the index of the read channel on which the data has arrived. Unlike readyRead(), it is emitted regardless of the current read channel.

channelReadyRead() can be emitted recursively - even for the same channel.

This function was introduced in Qt 5.7.

See also readyRead() and channelBytesWritten().

pub fn bytes_written(&self) -> Signal<(i64,)>

This signal is emitted every time a payload of data has been written to the device's current write channel. The bytes argument is set to the number of bytes that were written in this payload.

Returns a built-in Qt signal QIODevice::bytesWritten that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted every time a payload of data has been written to the device’s current write channel. The bytes argument is set to the number of bytes that were written in this payload.

bytesWritten() is not emitted recursively; if you reenter the event loop or call waitForBytesWritten() inside a slot connected to the bytesWritten() signal, the signal will not be reemitted (although waitForBytesWritten() may still return true).

See also readyRead().

pub fn channel_bytes_written(&self) -> Signal<(c_int, i64)>

This signal is emitted every time a payload of data has been written to the device. The bytes argument is set to the number of bytes that were written in this payload, while channel is the channel they were written to. Unlike bytesWritten(), it is emitted regardless of the current write channel.

Returns a built-in Qt signal QIODevice::channelBytesWritten that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted every time a payload of data has been written to the device. The bytes argument is set to the number of bytes that were written in this payload, while channel is the channel they were written to. Unlike bytesWritten(), it is emitted regardless of the current write channel.

channelBytesWritten() can be emitted recursively - even for the same channel.

This function was introduced in Qt 5.7.

See also bytesWritten() and channelReadyRead().

pub fn about_to_close(&self) -> Signal<()>

This signal is emitted when the device is about to close. Connect this signal if you have operations that need to be performed before the device closes (e.g., if you have data in a separate buffer that needs to be written to the device).

Returns a built-in Qt signal QIODevice::aboutToClose that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted when the device is about to close. Connect this signal if you have operations that need to be performed before the device closes (e.g., if you have data in a separate buffer that needs to be written to the device).

pub fn read_channel_finished(&self) -> Signal<()>

This signal is emitted when the input (reading) stream is closed in this device. It is emitted as soon as the closing is detected, which means that there might still be data available for reading with read().

Returns a built-in Qt signal QIODevice::readChannelFinished that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted when the input (reading) stream is closed in this device. It is emitted as soon as the closing is detected, which means that there might still be data available for reading with read().

This function was introduced in Qt 4.4.

See also atEnd() and read().

pub unsafe fn at_end(&self) -> bool

Returns true if the current read and write position is at the end of the device (i.e. there is no more data available for reading on the device); otherwise returns false.

Calls C++ function: virtual bool QIODevice::atEnd() const.

C++ documentation:

Returns true if the current read and write position is at the end of the device (i.e. there is no more data available for reading on the device); otherwise returns false.

For some devices, atEnd() can return true even though there is more data to read. This special case only applies to devices that generate data in direct response to you calling read() (e.g., /dev or /proc files on Unix and macOS, or console input / stdin on all platforms).

See also bytesAvailable(), read(), and isSequential().

pub unsafe fn bytes_available(&self) -> i64

Returns the number of bytes that are available for reading. This function is commonly used with sequential devices to determine the number of bytes to allocate in a buffer before reading.

Calls C++ function: virtual qint64 QIODevice::bytesAvailable() const.

C++ documentation:

Returns the number of bytes that are available for reading. This function is commonly used with sequential devices to determine the number of bytes to allocate in a buffer before reading.

Subclasses that reimplement this function must call the base implementation in order to include the size of the buffer of QIODevice. Example:

qint64 CustomDevice::bytesAvailable() const
{
      return buffer.size() + QIODevice::bytesAvailable();
}

See also bytesToWrite(), readyRead(), and isSequential().

pub unsafe fn bytes_to_write(&self) -> i64

For buffered devices, this function returns the number of bytes waiting to be written. For devices with no buffer, this function returns 0.

Calls C++ function: virtual qint64 QIODevice::bytesToWrite() const.

C++ documentation:

For buffered devices, this function returns the number of bytes waiting to be written. For devices with no buffer, this function returns 0.

Subclasses that reimplement this function must call the base implementation in order to include the size of the buffer of QIODevice.

See also bytesAvailable(), bytesWritten(), and isSequential().

pub unsafe fn can_read_line(&self) -> bool

Returns true if a complete line of data can be read from the device; otherwise returns false.

Calls C++ function: virtual bool QIODevice::canReadLine() const.

C++ documentation:

Returns true if a complete line of data can be read from the device; otherwise returns false.

Note that unbuffered devices, which have no way of determining what can be read, always return false.

This function is often called in conjunction with the readyRead() signal.

Subclasses that reimplement this function must call the base implementation in order to include the contents of the QIODevice's buffer. Example:

bool CustomDevice::canReadLine() const
{
      return buffer.contains(‘\n’) || QIODevice::canReadLine();
}

See also readyRead() and readLine().

pub unsafe fn close(&self)

First emits aboutToClose(), then closes the device and sets its OpenMode to NotOpen. The error string is also reset.

Calls C++ function: virtual void QIODevice::close().

C++ documentation:

First emits aboutToClose(), then closes the device and sets its OpenMode to NotOpen. The error string is also reset.

See also setOpenMode() and OpenMode.

pub unsafe fn commit_transaction(&self)

Completes a read transaction.

Calls C++ function: void QIODevice::commitTransaction().

C++ documentation:

Completes a read transaction.

For sequential devices, all data recorded in the internal buffer during the transaction will be discarded.

This function was introduced in Qt 5.7.

See also startTransaction() and rollbackTransaction().

pub unsafe fn current_read_channel(&self) -> c_int

Returns the index of the current read channel.

Calls C++ function: int QIODevice::currentReadChannel() const.

C++ documentation:

Returns the index of the current read channel.

This function was introduced in Qt 5.7.

See also setCurrentReadChannel(), readChannelCount(), and QProcess.

pub unsafe fn current_write_channel(&self) -> c_int

Returns the the index of the current write channel.

Calls C++ function: int QIODevice::currentWriteChannel() const.

C++ documentation:

Returns the the index of the current write channel.

This function was introduced in Qt 5.7.

See also setCurrentWriteChannel() and writeChannelCount().

pub unsafe fn error_string(&self) -> CppBox<QString>

Returns a human-readable description of the last device error that occurred.

Calls C++ function: QString QIODevice::errorString() const.

C++ documentation:

Returns a human-readable description of the last device error that occurred.

See also setErrorString().

pub unsafe fn get_char(&self, c: *mut c_char) -> bool

Reads one character from the device and stores it in c. If c is 0, the character is discarded. Returns true on success; otherwise returns false.

Calls C++ function: bool QIODevice::getChar(char* c).

C++ documentation:

Reads one character from the device and stores it in c. If c is 0, the character is discarded. Returns true on success; otherwise returns false.

See also read(), putChar(), and ungetChar().

pub unsafe fn is_open(&self) -> bool

Returns true if the device is open; otherwise returns false. A device is open if it can be read from and/or written to. By default, this function returns false if openMode() returns NotOpen.

Calls C++ function: bool QIODevice::isOpen() const.

C++ documentation:

Returns true if the device is open; otherwise returns false. A device is open if it can be read from and/or written to. By default, this function returns false if openMode() returns NotOpen.

See also openMode() and OpenMode.

pub unsafe fn is_readable(&self) -> bool

Returns true if data can be read from the device; otherwise returns false. Use bytesAvailable() to determine how many bytes can be read.

Calls C++ function: bool QIODevice::isReadable() const.

C++ documentation:

Returns true if data can be read from the device; otherwise returns false. Use bytesAvailable() to determine how many bytes can be read.

This is a convenience function which checks if the OpenMode of the device contains the ReadOnly flag.

See also openMode() and OpenMode.

pub unsafe fn is_sequential(&self) -> bool

Returns true if this device is sequential; otherwise returns false.

Calls C++ function: virtual bool QIODevice::isSequential() const.

C++ documentation:

Returns true if this device is sequential; otherwise returns false.

Sequential devices, as opposed to a random-access devices, have no concept of a start, an end, a size, or a current position, and they do not support seeking. You can only read from the device when it reports that data is available. The most common example of a sequential device is a network socket. On Unix, special files such as /dev/zero and fifo pipes are sequential.

Regular files, on the other hand, do support random access. They have both a size and a current position, and they also support seeking backwards and forwards in the data stream. Regular files are non-sequential.

See also bytesAvailable().

pub unsafe fn is_text_mode_enabled(&self) -> bool

Returns true if the Text flag is enabled; otherwise returns false.

Calls C++ function: bool QIODevice::isTextModeEnabled() const.

C++ documentation:

Returns true if the Text flag is enabled; otherwise returns false.

See also setTextModeEnabled().

pub unsafe fn is_transaction_started(&self) -> bool

Returns true if a transaction is in progress on the device, otherwise false.

Calls C++ function: bool QIODevice::isTransactionStarted() const.

C++ documentation:

Returns true if a transaction is in progress on the device, otherwise false.

This function was introduced in Qt 5.7.

See also startTransaction().

pub unsafe fn is_writable(&self) -> bool

Returns true if data can be written to the device; otherwise returns false.

Calls C++ function: bool QIODevice::isWritable() const.

C++ documentation:

Returns true if data can be written to the device; otherwise returns false.

This is a convenience function which checks if the OpenMode of the device contains the WriteOnly flag.

See also openMode() and OpenMode.

pub unsafe fn meta_object(&self) -> Ptr<QMetaObject>

Calls C++ function: virtual const QMetaObject* QIODevice::metaObject() const.

pub unsafe fn open(&self, mode: QFlags<OpenModeFlag>) -> bool

Opens the device and sets its OpenMode to mode. Returns true if successful; otherwise returns false. This function should be called from any reimplementations of open() or other functions that open the device.

Calls C++ function: virtual bool QIODevice::open(QFlags<QIODevice::OpenModeFlag> mode).

C++ documentation:

Opens the device and sets its OpenMode to mode. Returns true if successful; otherwise returns false. This function should be called from any reimplementations of open() or other functions that open the device.

See also openMode() and OpenMode.

pub unsafe fn open_mode(&self) -> QFlags<OpenModeFlag>

Returns the mode in which the device has been opened; i.e. ReadOnly or WriteOnly.

Calls C++ function: QFlags<QIODevice::OpenModeFlag> QIODevice::openMode() const.

C++ documentation:

Returns the mode in which the device has been opened; i.e. ReadOnly or WriteOnly.

See also setOpenMode() and OpenMode.

pub unsafe fn peek_2a(&self, data: *mut c_char, maxlen: i64) -> i64

Reads at most maxSize bytes from the device into data, without side effects (i.e., if you call read() after peek(), you will get the same data). Returns the number of bytes read. If an error occurs, such as when attempting to peek a device opened in WriteOnly mode, this function returns -1.

Calls C++ function: qint64 QIODevice::peek(char* data, qint64 maxlen).

C++ documentation:

Reads at most maxSize bytes from the device into data, without side effects (i.e., if you call read() after peek(), you will get the same data). Returns the number of bytes read. If an error occurs, such as when attempting to peek a device opened in WriteOnly mode, this function returns -1.

0 is returned when no more data is available for reading.

Example:

bool isExeFile(QFile *file)
{
      char buf[2];
      if (file->peek(buf, sizeof(buf)) == sizeof(buf))
          return (buf[0] == ‘M’ && buf[1] == ‘Z’);
      return false;
}

This function was introduced in Qt 4.1.

See also read().

pub unsafe fn peek_1a(&self, maxlen: i64) -> CppBox<QByteArray>

This is an overloaded function.

Calls C++ function: QByteArray QIODevice::peek(qint64 maxlen).

C++ documentation:

This is an overloaded function.

Peeks at most maxSize bytes from the device, returning the data peeked as a QByteArray.

Example:

bool isExeFile(QFile *file)
{
      return file->peek(2) == “MZ”;
}

This function has no way of reporting errors; returning an empty QByteArray can mean either that no data was currently available for peeking, or that an error occurred.

This function was introduced in Qt 4.1.

See also read().

pub unsafe fn pos(&self) -> i64

For random-access devices, this function returns the position that data is written to or read from. For sequential devices or closed devices, where there is no concept of a "current position", 0 is returned.

Calls C++ function: virtual qint64 QIODevice::pos() const.

C++ documentation:

For random-access devices, this function returns the position that data is written to or read from. For sequential devices or closed devices, where there is no concept of a “current position”, 0 is returned.

The current read/write position of the device is maintained internally by QIODevice, so reimplementing this function is not necessary. When subclassing QIODevice, use QIODevice::seek() to notify QIODevice about changes in the device position.

See also isSequential() and seek().

pub unsafe fn put_char(&self, c: c_char) -> bool

Writes the character c to the device. Returns true on success; otherwise returns false.

Calls C++ function: bool QIODevice::putChar(char c).

C++ documentation:

Writes the character c to the device. Returns true on success; otherwise returns false.

See also write(), getChar(), and ungetChar().

pub unsafe fn qt_metacall( &self, arg1: Call, arg2: c_int, arg3: *mut *mut c_void ) -> c_int

Calls C++ function: virtual int QIODevice::qt_metacall(QMetaObject::Call arg1, int arg2, void** arg3).

pub unsafe fn qt_metacast(&self, arg1: *const c_char) -> *mut c_void

Calls C++ function: virtual void* QIODevice::qt_metacast(const char* arg1).

pub unsafe fn read_2a(&self, data: *mut c_char, maxlen: i64) -> i64

Reads at most maxSize bytes from the device into data, and returns the number of bytes read. If an error occurs, such as when attempting to read from a device opened in WriteOnly mode, this function returns -1.

Calls C++ function: qint64 QIODevice::read(char* data, qint64 maxlen).

C++ documentation:

Reads at most maxSize bytes from the device into data, and returns the number of bytes read. If an error occurs, such as when attempting to read from a device opened in WriteOnly mode, this function returns -1.

0 is returned when no more data is available for reading. However, reading past the end of the stream is considered an error, so this function returns -1 in those cases (that is, reading on a closed socket or after a process has died).

See also readData(), readLine(), and write().

pub unsafe fn read_1a(&self, maxlen: i64) -> CppBox<QByteArray>

This is an overloaded function.

Calls C++ function: QByteArray QIODevice::read(qint64 maxlen).

C++ documentation:

This is an overloaded function.

Reads at most maxSize bytes from the device, and returns the data read as a QByteArray.

This function has no way of reporting errors; returning an empty QByteArray can mean either that no data was currently available for reading, or that an error occurred.

pub unsafe fn read_all(&self) -> CppBox<QByteArray>

Reads all remaining data from the device, and returns it as a byte array.

Calls C++ function: QByteArray QIODevice::readAll().

C++ documentation:

Reads all remaining data from the device, and returns it as a byte array.

This function has no way of reporting errors; returning an empty QByteArray can mean either that no data was currently available for reading, or that an error occurred.

pub unsafe fn read_channel_count(&self) -> c_int

Returns the number of available read channels if the device is open; otherwise returns 0.

Calls C++ function: int QIODevice::readChannelCount() const.

C++ documentation:

Returns the number of available read channels if the device is open; otherwise returns 0.

This function was introduced in Qt 5.7.

See also writeChannelCount() and QProcess.

pub unsafe fn read_line_2a(&self, data: *mut c_char, maxlen: i64) -> i64

This function reads a line of ASCII characters from the device, up to a maximum of maxSize - 1 bytes, stores the characters in data, and returns the number of bytes read. If a line could not be read but no error ocurred, this function returns 0. If an error occurs, this function returns the length of what could be read, or -1 if nothing was read.

Calls C++ function: qint64 QIODevice::readLine(char* data, qint64 maxlen).

C++ documentation:

This function reads a line of ASCII characters from the device, up to a maximum of maxSize - 1 bytes, stores the characters in data, and returns the number of bytes read. If a line could not be read but no error ocurred, this function returns 0. If an error occurs, this function returns the length of what could be read, or -1 if nothing was read.

A terminating '\0' byte is always appended to data, so maxSize must be larger than 1.

Data is read until either of the following conditions are met:

• The first '\n' character is read.
• maxSize - 1 bytes are read.
• The end of the device data is detected.

For example, the following code reads a line of characters from a file:

QFile file(“box.txt”);
if (file.open(QFile::ReadOnly)) {
      char buf[1024];
      qint64 lineLength = file.readLine(buf, sizeof(buf));
      if (lineLength != -1) {
          // the line is available in buf
      }
}

The newline character ('\n') is included in the buffer. If a newline is not encountered before maxSize - 1 bytes are read, a newline will not be inserted into the buffer. On windows newline characters are replaced with '\n'.

This function calls readLineData(), which is implemented using repeated calls to getChar(). You can provide a more efficient implementation by reimplementing readLineData() in your own subclass.

See also getChar(), read(), and write().

pub unsafe fn read_line_1a(&self, maxlen: i64) -> CppBox<QByteArray>

This is an overloaded function.

Calls C++ function: QByteArray QIODevice::readLine(qint64 maxlen = …).

C++ documentation:

This is an overloaded function.

Reads a line from the device, but no more than maxSize characters, and returns the result as a byte array.

This function has no way of reporting errors; returning an empty QByteArray can mean either that no data was currently available for reading, or that an error occurred.

pub unsafe fn read_line_0a(&self) -> CppBox<QByteArray>

This is an overloaded function.

Calls C++ function: QByteArray QIODevice::readLine().

C++ documentation:

This is an overloaded function.

Reads a line from the device, but no more than maxSize characters, and returns the result as a byte array.

This function has no way of reporting errors; returning an empty QByteArray can mean either that no data was currently available for reading, or that an error occurred.

pub unsafe fn reset(&self) -> bool

Seeks to the start of input for random-access devices. Returns true on success; otherwise returns false (for example, if the device is not open).

Calls C++ function: virtual bool QIODevice::reset().

C++ documentation:

Seeks to the start of input for random-access devices. Returns true on success; otherwise returns false (for example, if the device is not open).

Note that when using a QTextStream on a QFile, calling reset() on the QFile will not have the expected result because QTextStream buffers the file. Use the QTextStream::seek() function instead.

See also seek().

pub unsafe fn rollback_transaction(&self)

Rolls back a read transaction.

Calls C++ function: void QIODevice::rollbackTransaction().

C++ documentation:

Rolls back a read transaction.

Restores the input stream to the point of the startTransaction() call. This function is commonly used to rollback the transaction when an incomplete read was detected prior to committing the transaction.

This function was introduced in Qt 5.7.

See also startTransaction() and commitTransaction().

pub unsafe fn seek(&self, pos: i64) -> bool

For random-access devices, this function sets the current position to pos, returning true on success, or false if an error occurred. For sequential devices, the default behavior is to produce a warning and return false.

Calls C++ function: virtual bool QIODevice::seek(qint64 pos).

C++ documentation:

For random-access devices, this function sets the current position to pos, returning true on success, or false if an error occurred. For sequential devices, the default behavior is to produce a warning and return false.

When subclassing QIODevice, you must call QIODevice::seek() at the start of your function to ensure integrity with QIODevice's built-in buffer.

See also pos() and isSequential().

pub unsafe fn set_current_read_channel(&self, channel: c_int)

Sets the current read channel of the QIODevice to the given channel. The current input channel is used by the functions read(), readAll(), readLine(), and getChar(). It also determines which channel triggers QIODevice to emit readyRead().

Calls C++ function: void QIODevice::setCurrentReadChannel(int channel).

C++ documentation:

Sets the current read channel of the QIODevice to the given channel. The current input channel is used by the functions read(), readAll(), readLine(), and getChar(). It also determines which channel triggers QIODevice to emit readyRead().

This function was introduced in Qt 5.7.

See also currentReadChannel(), readChannelCount(), and QProcess.

pub unsafe fn set_current_write_channel(&self, channel: c_int)

Sets the current write channel of the QIODevice to the given channel. The current output channel is used by the functions write(), putChar(). It also determines which channel triggers QIODevice to emit bytesWritten().

Calls C++ function: void QIODevice::setCurrentWriteChannel(int channel).

C++ documentation:

Sets the current write channel of the QIODevice to the given channel. The current output channel is used by the functions write(), putChar(). It also determines which channel triggers QIODevice to emit bytesWritten().

This function was introduced in Qt 5.7.

See also currentWriteChannel() and writeChannelCount().

pub unsafe fn set_text_mode_enabled(&self, enabled: bool)

If enabled is true, this function sets the Text flag on the device; otherwise the Text flag is removed. This feature is useful for classes that provide custom end-of-line handling on a QIODevice.

Calls C++ function: void QIODevice::setTextModeEnabled(bool enabled).

C++ documentation:

If enabled is true, this function sets the Text flag on the device; otherwise the Text flag is removed. This feature is useful for classes that provide custom end-of-line handling on a QIODevice.

The IO device should be opened before calling this function.

See also isTextModeEnabled(), open(), and setOpenMode().

pub unsafe fn size(&self) -> i64

For open random-access devices, this function returns the size of the device. For open sequential devices, bytesAvailable() is returned.

Calls C++ function: virtual qint64 QIODevice::size() const.

C++ documentation:

For open random-access devices, this function returns the size of the device. For open sequential devices, bytesAvailable() is returned.

If the device is closed, the size returned will not reflect the actual size of the device.

See also isSequential() and pos().

pub unsafe fn skip(&self, max_size: i64) -> i64

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Skips up to maxSize bytes from the device. Returns the number of bytes actually skipped, or -1 on error.

Calls C++ function: qint64 QIODevice::skip(qint64 maxSize).

C++ documentation:

Skips up to maxSize bytes from the device. Returns the number of bytes actually skipped, or -1 on error.

This function does not wait and only discards the data that is already available for reading.

If the device is opened in text mode, end-of-line terminators are translated to '\n' symbols and count as a single byte identically to the read() and peek() behavior.

This function works for all devices, including sequential ones that cannot seek(). It is optimized to skip unwanted data after a peek() call.

For random-access devices, skip() can be used to seek forward from the current position. Negative maxSize values are not allowed.

This function was introduced in Qt 5.10.

See also peek(), seek(), and read().

pub unsafe fn start_transaction(&self)

Starts a new read transaction on the device.

Calls C++ function: void QIODevice::startTransaction().

C++ documentation:

Starts a new read transaction on the device.

Defines a restorable point within the sequence of read operations. For sequential devices, read data will be duplicated internally to allow recovery in case of incomplete reads. For random-access devices, this function saves the current position. Call commitTransaction() or rollbackTransaction() to finish the transaction.

Note: Nesting transactions is not supported.

This function was introduced in Qt 5.7.

See also commitTransaction() and rollbackTransaction().

pub unsafe fn unget_char(&self, c: c_char)

Puts the character c back into the device, and decrements the current position unless the position is 0. This function is usually called to "undo" a getChar() operation, such as when writing a backtracking parser.

Calls C++ function: void QIODevice::ungetChar(char c).

C++ documentation:

Puts the character c back into the device, and decrements the current position unless the position is 0. This function is usually called to “undo” a getChar() operation, such as when writing a backtracking parser.

If c was not previously read from the device, the behavior is undefined.

Note: This function is not available while a transaction is in progress.

pub unsafe fn wait_for_bytes_written(&self, msecs: c_int) -> bool

For buffered devices, this function waits until a payload of buffered written data has been written to the device and the bytesWritten() signal has been emitted, or until msecs milliseconds have passed. If msecs is -1, this function will not time out. For unbuffered devices, it returns immediately.

Calls C++ function: virtual bool QIODevice::waitForBytesWritten(int msecs).

C++ documentation:

For buffered devices, this function waits until a payload of buffered written data has been written to the device and the bytesWritten() signal has been emitted, or until msecs milliseconds have passed. If msecs is -1, this function will not time out. For unbuffered devices, it returns immediately.

Returns true if a payload of data was written to the device; otherwise returns false (i.e. if the operation timed out, or if an error occurred).

This function can operate without an event loop. It is useful when writing non-GUI applications and when performing I/O operations in a non-GUI thread.

If called from within a slot connected to the bytesWritten() signal, bytesWritten() will not be reemitted.

Reimplement this function to provide a blocking API for a custom device. The default implementation does nothing, and returns false.

Warning: Calling this function from the main (GUI) thread might cause your user interface to freeze.

See also waitForReadyRead().

pub unsafe fn wait_for_ready_read(&self, msecs: c_int) -> bool

Blocks until new data is available for reading and the readyRead() signal has been emitted, or until msecs milliseconds have passed. If msecs is -1, this function will not time out.

Calls C++ function: virtual bool QIODevice::waitForReadyRead(int msecs).

C++ documentation:

Blocks until new data is available for reading and the readyRead() signal has been emitted, or until msecs milliseconds have passed. If msecs is -1, this function will not time out.

Returns true if new data is available for reading; otherwise returns false (if the operation timed out or if an error occurred).

This function can operate without an event loop. It is useful when writing non-GUI applications and when performing I/O operations in a non-GUI thread.

If called from within a slot connected to the readyRead() signal, readyRead() will not be reemitted.

Reimplement this function to provide a blocking API for a custom device. The default implementation does nothing, and returns false.

Warning: Calling this function from the main (GUI) thread might cause your user interface to freeze.

See also waitForBytesWritten().

pub unsafe fn write_char_i64(&self, data: *const c_char, len: i64) -> i64

Writes at most maxSize bytes of data from data to the device. Returns the number of bytes that were actually written, or -1 if an error occurred.

Calls C++ function: qint64 QIODevice::write(const char* data, qint64 len).

C++ documentation:

Writes at most maxSize bytes of data from data to the device. Returns the number of bytes that were actually written, or -1 if an error occurred.

See also read() and writeData().

pub unsafe fn write_char(&self, data: *const c_char) -> i64

This is an overloaded function.

Calls C++ function: qint64 QIODevice::write(const char* data).

C++ documentation:

This is an overloaded function.

Writes data from a zero-terminated string of 8-bit characters to the device. Returns the number of bytes that were actually written, or -1 if an error occurred. This is equivalent to

...
QIODevice::write(data, qstrlen(data));
...

This function was introduced in Qt 4.5.

See also read() and writeData().

pub unsafe fn write_q_byte_array( &self, data: impl CastInto<Ref<QByteArray>> ) -> i64

This is an overloaded function.

Calls C++ function: qint64 QIODevice::write(const QByteArray& data).

C++ documentation:

This is an overloaded function.

Writes the content of byteArray to the device. Returns the number of bytes that were actually written, or -1 if an error occurred.

See also read() and writeData().

pub unsafe fn write_channel_count(&self) -> c_int

Returns the number of available write channels if the device is open; otherwise returns 0.

Calls C++ function: int QIODevice::writeChannelCount() const.

C++ documentation:

Returns the number of available write channels if the device is open; otherwise returns 0.

This function was introduced in Qt 5.7.

See also readChannelCount().

Methods from Deref<Target = QObject>

pub unsafe fn find_child<T>( &self, name: &str ) -> Result<QPtr<T>, FindChildError>

where QObject: DynamicCast<T>, T: StaticUpcast<QObject>,

Finds a child of self with the specified object name and casts it to type T.

The search is performed recursively. If there is more than one child matching the search, the most direct ancestor is returned. If there are several direct ancestors, it is undefined which one will be returned.

Returns an error if there is no child object with object name name or the found object cannot be cast to T.

pub fn destroyed(&self) -> Signal<(*mut QObject,)>

This signal is emitted immediately before the object obj is destroyed, and can not be blocked.

Returns a built-in Qt signal QObject::destroyed that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted immediately before the object obj is destroyed, and can not be blocked.

All the objects's children are destroyed immediately after this signal is emitted.

See also deleteLater() and QPointer.

pub fn object_name_changed(&self) -> Signal<(*const QString,)>

This signal is emitted after the object's name has been changed. The new object name is passed as objectName.

Returns a built-in Qt signal QObject::objectNameChanged that can be passed to qt_core::Signal::connect.

C++ documentation:

This signal is emitted after the object’s name has been changed. The new object name is passed as objectName.

Note: This is a private signal. It can be used in signal connections but cannot be emitted by the user.

Note: Notifier signal for property objectName.

See also QObject::objectName.

pub fn slot_delete_later(&self) -> Receiver<()>

Schedules this object for deletion.

Returns a built-in Qt slot QObject::deleteLater that can be passed to qt_core::Signal::connect.

C++ documentation:

Schedules this object for deletion.

The object will be deleted when control returns to the event loop. If the event loop is not running when this function is called (e.g. deleteLater() is called on an object before QCoreApplication::exec()), the object will be deleted once the event loop is started. If deleteLater() is called after the main event loop has stopped, the object will not be deleted. Since Qt 4.8, if deleteLater() is called on an object that lives in a thread with no running event loop, the object will be destroyed when the thread finishes.

Note that entering and leaving a new event loop (e.g., by opening a modal dialog) will not perform the deferred deletion; for the object to be deleted, the control must return to the event loop from which deleteLater() was called.

Note: It is safe to call this function more than once; when the first deferred deletion event is delivered, any pending events for the object are removed from the event queue.

See also destroyed() and QPointer.

pub unsafe fn block_signals(&self, b: bool) -> bool

If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). If block is false, no such blocking will occur.

Calls C++ function: bool QObject::blockSignals(bool b).

C++ documentation:

If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). If block is false, no such blocking will occur.

The return value is the previous value of signalsBlocked().

Note that the destroyed() signal will be emitted even if the signals for this object have been blocked.

Signals emitted while being blocked are not buffered.

See also signalsBlocked() and QSignalBlocker.

pub unsafe fn children(&self) -> Ref<QListOfQObject>

Returns a list of child objects. The QObjectList class is defined in the <QObject> header file as the following:

Calls C++ function: const QList<QObject*>& QObject::children() const.

C++ documentation:

Returns a list of child objects. The QObjectList class is defined in the <QObject> header file as the following:

  typedef QList<QObject*> QObjectList;

The first child added is the first object in the list and the last child added is the last object in the list, i.e. new children are appended at the end.

Note that the list order changes when QWidget children are raised or lowered. A widget that is raised becomes the last object in the list, and a widget that is lowered becomes the first object in the list.

See also findChild(), findChildren(), parent(), and setParent().

pub unsafe fn delete_later(&self)

Schedules this object for deletion.

Calls C++ function: [slot] void QObject::deleteLater().

C++ documentation:

Schedules this object for deletion.

The object will be deleted when control returns to the event loop. If the event loop is not running when this function is called (e.g. deleteLater() is called on an object before QCoreApplication::exec()), the object will be deleted once the event loop is started. If deleteLater() is called after the main event loop has stopped, the object will not be deleted. Since Qt 4.8, if deleteLater() is called on an object that lives in a thread with no running event loop, the object will be destroyed when the thread finishes.

Note that entering and leaving a new event loop (e.g., by opening a modal dialog) will not perform the deferred deletion; for the object to be deleted, the control must return to the event loop from which deleteLater() was called.

Note: It is safe to call this function more than once; when the first deferred deletion event is delivered, any pending events for the object are removed from the event queue.

See also destroyed() and QPointer.

pub unsafe fn disconnect_char_q_object_char( &self, signal: *const c_char, receiver: impl CastInto<Ptr<QObject>>, member: *const c_char ) -> bool

This function overloads disconnect().

Calls C++ function: bool QObject::disconnect(const char* signal = …, const QObject* receiver = …, const char* member = …) const.

C++ documentation:

This function overloads disconnect().

Disconnects signal from method of receiver.

A signal-slot connection is removed when either of the objects involved are destroyed.

Note: This function is thread-safe.

pub unsafe fn disconnect_q_object_char( &self, receiver: impl CastInto<Ptr<QObject>>, member: *const c_char ) -> bool

This function overloads disconnect().

Calls C++ function: bool QObject::disconnect(const QObject* receiver, const char* member = …) const.

C++ documentation:

This function overloads disconnect().

Disconnects all signals in this object from receiver's method.

A signal-slot connection is removed when either of the objects involved are destroyed.

pub unsafe fn disconnect_char_q_object( &self, signal: *const c_char, receiver: impl CastInto<Ptr<QObject>> ) -> bool

This function overloads disconnect().

Calls C++ function: bool QObject::disconnect(const char* signal = …, const QObject* receiver = …) const.

C++ documentation:

This function overloads disconnect().

Disconnects signal from method of receiver.

A signal-slot connection is removed when either of the objects involved are destroyed.

Note: This function is thread-safe.

pub unsafe fn disconnect_char(&self, signal: *const c_char) -> bool

This function overloads disconnect().

Calls C++ function: bool QObject::disconnect(const char* signal = …) const.

C++ documentation:

This function overloads disconnect().

Disconnects signal from method of receiver.

A signal-slot connection is removed when either of the objects involved are destroyed.

Note: This function is thread-safe.

pub unsafe fn disconnect(&self) -> bool

This function overloads disconnect().

Calls C++ function: bool QObject::disconnect() const.

C++ documentation:

This function overloads disconnect().

Disconnects signal from method of receiver.

A signal-slot connection is removed when either of the objects involved are destroyed.

Note: This function is thread-safe.

pub unsafe fn disconnect_q_object( &self, receiver: impl CastInto<Ptr<QObject>> ) -> bool

This function overloads disconnect().

Calls C++ function: bool QObject::disconnect(const QObject* receiver) const.

C++ documentation:

This function overloads disconnect().

Disconnects all signals in this object from receiver's method.

A signal-slot connection is removed when either of the objects involved are destroyed.

pub unsafe fn dump_object_info_mut(&self)

Dumps information about signal connections, etc. for this object to the debug output.

Calls C++ function: void QObject::dumpObjectInfo().

C++ documentation:

Dumps information about signal connections, etc. for this object to the debug output.

Note: before Qt 5.9, this function was not const.

See also dumpObjectTree().

pub unsafe fn dump_object_info(&self)

Dumps information about signal connections, etc. for this object to the debug output.

Calls C++ function: void QObject::dumpObjectInfo() const.

C++ documentation:

Dumps information about signal connections, etc. for this object to the debug output.

Note: before Qt 5.9, this function was not const.

See also dumpObjectTree().

pub unsafe fn dump_object_tree_mut(&self)

Dumps a tree of children to the debug output.

Calls C++ function: void QObject::dumpObjectTree().

C++ documentation:

Dumps a tree of children to the debug output.

Note: before Qt 5.9, this function was not const.

See also dumpObjectInfo().

pub unsafe fn dump_object_tree(&self)

Dumps a tree of children to the debug output.

Calls C++ function: void QObject::dumpObjectTree() const.

C++ documentation:

Dumps a tree of children to the debug output.

Note: before Qt 5.9, this function was not const.

See also dumpObjectInfo().

pub unsafe fn dynamic_property_names(&self) -> CppBox<QListOfQByteArray>

Returns the names of all properties that were dynamically added to the object using setProperty().

Calls C++ function: QList<QByteArray> QObject::dynamicPropertyNames() const.

C++ documentation:

Returns the names of all properties that were dynamically added to the object using setProperty().

This function was introduced in Qt 4.2.

pub unsafe fn eq(&self, p: impl CastInto<Ref<QPointerOfQObject>>) -> bool

Returns true if c1 and c2 are the same Unicode character; otherwise returns false.

Calls C++ function: bool operator==(QObject* o, const QPointer<QObject>& p).

Warning: no exact match found in C++ documentation. Below is the C++ documentation for bool operator==(QChar c1, QChar c2):

Returns true if c1 and c2 are the same Unicode character; otherwise returns false.

pub unsafe fn event(&self, event: impl CastInto<Ptr<QEvent>>) -> bool

This virtual function receives events to an object and should return true if the event e was recognized and processed.

Calls C++ function: virtual bool QObject::event(QEvent* event).

C++ documentation:

This virtual function receives events to an object and should return true if the event e was recognized and processed.

The event() function can be reimplemented to customize the behavior of an object.

Make sure you call the parent event class implementation for all the events you did not handle.

Example:

class MyClass : public QWidget
{
      Q_OBJECT
public:
      MyClass(QWidget *parent = 0);
      ~MyClass();
      bool event(QEvent* ev)
      {
          if (ev->type() == QEvent::PolishRequest) {
              // overwrite handling of PolishRequest if any
              doThings();
              return true;
          } else  if (ev->type() == QEvent::Show) {
              // complement handling of Show if any
              doThings2();
              QWidget::event(ev);
              return true;
          }
          // Make sure the rest of events are handled
          return QWidget::event(ev);
      }
};

See also installEventFilter(), timerEvent(), QCoreApplication::sendEvent(), and QCoreApplication::postEvent().

pub unsafe fn event_filter( &self, watched: impl CastInto<Ptr<QObject>>, event: impl CastInto<Ptr<QEvent>> ) -> bool

Filters events if this object has been installed as an event filter for the watched object.

Calls C++ function: virtual bool QObject::eventFilter(QObject* watched, QEvent* event).

C++ documentation:

Filters events if this object has been installed as an event filter for the watched object.

In your reimplementation of this function, if you want to filter the event out, i.e. stop it being handled further, return true; otherwise return false.

Example:

class MainWindow : public QMainWindow
{
public:
      MainWindow();
protected:
      bool eventFilter(QObject obj, QEvent ev);
private:
      QTextEdit *textEdit;
};
MainWindow::MainWindow()
{
      textEdit = new QTextEdit;
      setCentralWidget(textEdit);
      textEdit->installEventFilter(this);
}
bool MainWindow::eventFilter(QObject obj, QEvent event)
{
      if (obj == textEdit) {
          if (event->type() == QEvent::KeyPress) {
              QKeyEvent keyEvent = static_cast<QKeyEvent>(event);
              qDebug() << “Ate key press” << keyEvent->key();
              return true;
          } else {
              return false;
          }
      } else {
          // pass the event on to the parent class
          return QMainWindow::eventFilter(obj, event);
      }
}

Notice in the example above that unhandled events are passed to the base class's eventFilter() function, since the base class might have reimplemented eventFilter() for its own internal purposes.

Warning: If you delete the receiver object in this function, be sure to return true. Otherwise, Qt will forward the event to the deleted object and the program might crash.

See also installEventFilter().

pub unsafe fn find_child_q_object_2a( &self, a_name: impl CastInto<Ref<QString>>, options: QFlags<FindChildOption> ) -> QPtr<QObject>

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

Calls C++ function: QObject* QObject::findChild<QObject*>(const QString& aName = …, QFlags<Qt::FindChildOption> options = …) const.

C++ documentation:

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

If there is more than one child matching the search, the most direct ancestor is returned. If there are several direct ancestors, it is undefined which one will be returned. In that case, findChildren() should be used.

This example returns a child QPushButton of parentWidget named "button1", even if the button isn't a direct child of the parent:

QPushButton button = parentWidget->findChild<QPushButton >(“button1”);

This example returns a QListWidget child of parentWidget:

QListWidget list = parentWidget->findChild<QListWidget >();

This example returns a child QPushButton of parentWidget (its direct parent) named "button1":

QPushButton button = parentWidget->findChild<QPushButton >(“button1”, Qt::FindDirectChildrenOnly);

This example returns a QListWidget child of parentWidget, its direct parent:

QListWidget list = parentWidget->findChild<QListWidget >(QString(), Qt::FindDirectChildrenOnly);

See also findChildren().

pub unsafe fn find_child_q_object_1a( &self, a_name: impl CastInto<Ref<QString>> ) -> QPtr<QObject>

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

Calls C++ function: QObject* QObject::findChild<QObject*>(const QString& aName = …) const.

C++ documentation:

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

If there is more than one child matching the search, the most direct ancestor is returned. If there are several direct ancestors, it is undefined which one will be returned. In that case, findChildren() should be used.

This example returns a child QPushButton of parentWidget named "button1", even if the button isn't a direct child of the parent:

QPushButton button = parentWidget->findChild<QPushButton >(“button1”);

This example returns a QListWidget child of parentWidget:

QListWidget list = parentWidget->findChild<QListWidget >();

This example returns a child QPushButton of parentWidget (its direct parent) named "button1":

QPushButton button = parentWidget->findChild<QPushButton >(“button1”, Qt::FindDirectChildrenOnly);

This example returns a QListWidget child of parentWidget, its direct parent:

QListWidget list = parentWidget->findChild<QListWidget >(QString(), Qt::FindDirectChildrenOnly);

See also findChildren().

pub unsafe fn find_child_q_object_0a(&self) -> QPtr<QObject>

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

Calls C++ function: QObject* QObject::findChild<QObject*>() const.

C++ documentation:

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

If there is more than one child matching the search, the most direct ancestor is returned. If there are several direct ancestors, it is undefined which one will be returned. In that case, findChildren() should be used.

This example returns a child QPushButton of parentWidget named "button1", even if the button isn't a direct child of the parent:

QPushButton button = parentWidget->findChild<QPushButton >(“button1”);

This example returns a QListWidget child of parentWidget:

QListWidget list = parentWidget->findChild<QListWidget >();

This example returns a child QPushButton of parentWidget (its direct parent) named "button1":

QPushButton button = parentWidget->findChild<QPushButton >(“button1”, Qt::FindDirectChildrenOnly);

This example returns a QListWidget child of parentWidget, its direct parent:

QListWidget list = parentWidget->findChild<QListWidget >(QString(), Qt::FindDirectChildrenOnly);

See also findChildren().

pub unsafe fn find_children_q_object_q_string_q_flags_find_child_option( &self, a_name: impl CastInto<Ref<QString>>, options: QFlags<FindChildOption> ) -> CppBox<QListOfQObject>

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>(const QString& aName = …, QFlags<Qt::FindChildOption> options = …) const.

C++ documentation:

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

The following example shows how to find a list of child QWidgets of the specified parentWidget named widgetname:

QList<QWidget > widgets = parentWidget.findChildren<QWidget >(“widgetname”);

This example returns all QPushButtons that are children of parentWidget:

QList<QPushButton > allPButtons = parentWidget.findChildren<QPushButton >();

This example returns all QPushButtons that are immediate children of parentWidget:

QList<QPushButton > childButtons = parentWidget.findChildren<QPushButton >(QString(), Qt::FindDirectChildrenOnly);

See also findChild().

pub unsafe fn find_children_q_object_q_reg_exp_q_flags_find_child_option( &self, re: impl CastInto<Ref<QRegExp>>, options: QFlags<FindChildOption> ) -> CppBox<QListOfQObject>

This function overloads findChildren().

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>(const QRegExp& re, QFlags<Qt::FindChildOption> options = …) const.

C++ documentation:

This function overloads findChildren().

Returns the children of this object that can be cast to type T and that have names matching the regular expression regExp, or an empty list if there are no such objects. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

pub unsafe fn find_children_q_object_q_regular_expression_q_flags_find_child_option( &self, re: impl CastInto<Ref<QRegularExpression>>, options: QFlags<FindChildOption> ) -> CppBox<QListOfQObject>

This function overloads findChildren().

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>(const QRegularExpression& re, QFlags<Qt::FindChildOption> options = …) const.

C++ documentation:

This function overloads findChildren().

Returns the children of this object that can be cast to type T and that have names matching the regular expression re, or an empty list if there are no such objects. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

This function was introduced in Qt 5.0.

pub unsafe fn find_children_q_object_q_string( &self, a_name: impl CastInto<Ref<QString>> ) -> CppBox<QListOfQObject>

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>(const QString& aName = …) const.

C++ documentation:

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

The following example shows how to find a list of child QWidgets of the specified parentWidget named widgetname:

QList<QWidget > widgets = parentWidget.findChildren<QWidget >(“widgetname”);

This example returns all QPushButtons that are children of parentWidget:

QList<QPushButton > allPButtons = parentWidget.findChildren<QPushButton >();

This example returns all QPushButtons that are immediate children of parentWidget:

QList<QPushButton > childButtons = parentWidget.findChildren<QPushButton >(QString(), Qt::FindDirectChildrenOnly);

See also findChild().

pub unsafe fn find_children_q_object(&self) -> CppBox<QListOfQObject>

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>() const.

C++ documentation:

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. Omitting the name argument causes all object names to be matched. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

The following example shows how to find a list of child QWidgets of the specified parentWidget named widgetname:

QList<QWidget > widgets = parentWidget.findChildren<QWidget >(“widgetname”);

This example returns all QPushButtons that are children of parentWidget:

QList<QPushButton > allPButtons = parentWidget.findChildren<QPushButton >();

This example returns all QPushButtons that are immediate children of parentWidget:

QList<QPushButton > childButtons = parentWidget.findChildren<QPushButton >(QString(), Qt::FindDirectChildrenOnly);

See also findChild().

pub unsafe fn find_children_q_object_q_reg_exp( &self, re: impl CastInto<Ref<QRegExp>> ) -> CppBox<QListOfQObject>

This function overloads findChildren().

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>(const QRegExp& re) const.

C++ documentation:

This function overloads findChildren().

Returns the children of this object that can be cast to type T and that have names matching the regular expression regExp, or an empty list if there are no such objects. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

pub unsafe fn find_children_q_object_q_regular_expression( &self, re: impl CastInto<Ref<QRegularExpression>> ) -> CppBox<QListOfQObject>

This function overloads findChildren().

Calls C++ function: QList<QObject*> QObject::findChildren<QObject*>(const QRegularExpression& re) const.

C++ documentation:

This function overloads findChildren().

Returns the children of this object that can be cast to type T and that have names matching the regular expression re, or an empty list if there are no such objects. The search is performed recursively, unless options specifies the option FindDirectChildrenOnly.

This function was introduced in Qt 5.0.

pub unsafe fn inherits(&self, classname: *const c_char) -> bool

Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false.

Calls C++ function: bool QObject::inherits(const char* classname) const.

C++ documentation:

Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false.

A class is considered to inherit itself.

Example:

QTimer *timer = new QTimer;         // QTimer inherits QObject
timer->inherits(“QTimer”);          // returns true
timer->inherits(“QObject”);         // returns true
timer->inherits(“QAbstractButton”); // returns false
// QVBoxLayout inherits QObject and QLayoutItem
QVBoxLayout *layout = new QVBoxLayout;
layout->inherits(“QObject”);        // returns true
layout->inherits(“QLayoutItem”);    // returns true (even though QLayoutItem is not a QObject)

If you need to determine whether an object is an instance of a particular class for the purpose of casting it, consider using qobject_cast<Type *>(object) instead.

See also metaObject() and qobject_cast().

pub unsafe fn install_event_filter( &self, filter_obj: impl CastInto<Ptr<QObject>> )

Installs an event filter filterObj on this object. For example:

Calls C++ function: void QObject::installEventFilter(QObject* filterObj).

C++ documentation:

Installs an event filter filterObj on this object. For example:

  monitoredObj->installEventFilter(filterObj);

An event filter is an object that receives all events that are sent to this object. The filter can either stop the event or forward it to this object. The event filter filterObj receives events via its eventFilter() function. The eventFilter() function must return true if the event should be filtered, (i.e. stopped); otherwise it must return false.

If multiple event filters are installed on a single object, the filter that was installed last is activated first.

Here's a KeyPressEater class that eats the key presses of its monitored objects:

class KeyPressEater : public QObject
{
      Q_OBJECT
      ...
protected:
      bool eventFilter(QObject obj, QEvent event);
};
bool KeyPressEater::eventFilter(QObject obj, QEvent event)
{
      if (event->type() == QEvent::KeyPress) {
          QKeyEvent keyEvent = static_cast<QKeyEvent >(event);
          qDebug(“Ate key press %d”, keyEvent->key());
          return true;
      } else {
          // standard event processing
          return QObject::eventFilter(obj, event);
      }
}

And here's how to install it on two widgets:

KeyPressEater keyPressEater = new KeyPressEater(this);
QPushButton pushButton = new QPushButton(this);
QListView *listView = new QListView(this);
pushButton->installEventFilter(keyPressEater);
listView->installEventFilter(keyPressEater);

The QShortcut class, for example, uses this technique to intercept shortcut key presses.

Warning: If you delete the receiver object in your eventFilter() function, be sure to return true. If you return false, Qt sends the event to the deleted object and the program will crash.

Note that the filtering object must be in the same thread as this object. If filterObj is in a different thread, this function does nothing. If either filterObj or this object are moved to a different thread after calling this function, the event filter will not be called until both objects have the same thread affinity again (it is not removed).

See also removeEventFilter(), eventFilter(), and event().

pub unsafe fn is_widget_type(&self) -> bool

Returns true if the object is a widget; otherwise returns false.

Calls C++ function: bool QObject::isWidgetType() const.

C++ documentation:

Returns true if the object is a widget; otherwise returns false.

Calling this function is equivalent to calling inherits("QWidget"), except that it is much faster.

pub unsafe fn is_window_type(&self) -> bool

Returns true if the object is a window; otherwise returns false.

Calls C++ function: bool QObject::isWindowType() const.

C++ documentation:

Returns true if the object is a window; otherwise returns false.

Calling this function is equivalent to calling inherits("QWindow"), except that it is much faster.

pub unsafe fn kill_timer(&self, id: c_int)

Kills the timer with timer identifier, id.

Calls C++ function: void QObject::killTimer(int id).

C++ documentation:

Kills the timer with timer identifier, id.

The timer identifier is returned by startTimer() when a timer event is started.

See also timerEvent() and startTimer().

pub unsafe fn meta_object(&self) -> Ptr<QMetaObject>

Returns a pointer to the meta-object of this object.

Calls C++ function: virtual const QMetaObject* QObject::metaObject() const.

C++ documentation:

Returns a pointer to the meta-object of this object.

A meta-object contains information about a class that inherits QObject, e.g. class name, superclass name, properties, signals and slots. Every QObject subclass that contains the Q_OBJECT macro will have a meta-object.

The meta-object information is required by the signal/slot connection mechanism and the property system. The inherits() function also makes use of the meta-object.

If you have no pointer to an actual object instance but still want to access the meta-object of a class, you can use staticMetaObject.

Example:

QObject *obj = new QPushButton;
obj->metaObject()->className();             // returns “QPushButton”
QPushButton::staticMetaObject.className();  // returns “QPushButton”

See also staticMetaObject.

pub unsafe fn move_to_thread(&self, thread: impl CastInto<Ptr<QThread>>)

Changes the thread affinity for this object and its children. The object cannot be moved if it has a parent. Event processing will continue in the targetThread.

Calls C++ function: void QObject::moveToThread(QThread* thread).

C++ documentation:

Changes the thread affinity for this object and its children. The object cannot be moved if it has a parent. Event processing will continue in the targetThread.

To move an object to the main thread, use QApplication::instance() to retrieve a pointer to the current application, and then use QApplication::thread() to retrieve the thread in which the application lives. For example:

myObject->moveToThread(QApplication::instance()->thread());

If targetThread is zero, all event processing for this object and its children stops.

Note that all active timers for the object will be reset. The timers are first stopped in the current thread and restarted (with the same interval) in the targetThread. As a result, constantly moving an object between threads can postpone timer events indefinitely.

A QEvent::ThreadChange event is sent to this object just before the thread affinity is changed. You can handle this event to perform any special processing. Note that any new events that are posted to this object will be handled in the targetThread.

Warning: This function is not thread-safe; the current thread must be same as the current thread affinity. In other words, this function can only "push" an object from the current thread to another thread, it cannot "pull" an object from any arbitrary thread to the current thread.

See also thread().

pub unsafe fn object_name(&self) -> CppBox<QString>

This property holds the name of this object

Calls C++ function: QString QObject::objectName() const.

C++ documentation:

This property holds the name of this object

You can find an object by name (and type) using findChild(). You can find a set of objects with findChildren().

qDebug(“MyClass::setPrecision(): (%s) invalid precision %f”,
         qPrintable(objectName()), newPrecision);

By default, this property contains an empty string.

Access functions:

QString	objectName() const
void	setObjectName(const QString &name)

Notifier signal:

void

objectNameChanged(const QString &objectName)

[see note below]

Note: This is a private signal. It can be used in signal connections but cannot be emitted by the user.

See also metaObject() and QMetaObject::className().

pub unsafe fn parent(&self) -> QPtr<QObject>

Returns a pointer to the parent object.

Calls C++ function: QObject* QObject::parent() const.

C++ documentation:

Returns a pointer to the parent object.

See also setParent() and children().

pub unsafe fn property(&self, name: *const c_char) -> CppBox<QVariant>

Returns the value of the object's name property.

Calls C++ function: QVariant QObject::property(const char* name) const.

C++ documentation:

Returns the value of the object’s name property.

If no such property exists, the returned variant is invalid.

Information about all available properties is provided through the metaObject() and dynamicPropertyNames().

See also setProperty(), QVariant::isValid(), metaObject(), and dynamicPropertyNames().

pub unsafe fn qt_metacall( &self, arg1: Call, arg2: c_int, arg3: *mut *mut c_void ) -> c_int

Calls C++ function: virtual int QObject::qt_metacall(QMetaObject::Call arg1, int arg2, void** arg3).

pub unsafe fn qt_metacast(&self, arg1: *const c_char) -> *mut c_void

Calls C++ function: virtual void* QObject::qt_metacast(const char* arg1).

pub unsafe fn remove_event_filter(&self, obj: impl CastInto<Ptr<QObject>>)

Removes an event filter object obj from this object. The request is ignored if such an event filter has not been installed.

Calls C++ function: void QObject::removeEventFilter(QObject* obj).

C++ documentation:

Removes an event filter object obj from this object. The request is ignored if such an event filter has not been installed.

All event filters for this object are automatically removed when this object is destroyed.

It is always safe to remove an event filter, even during event filter activation (i.e. from the eventFilter() function).

See also installEventFilter(), eventFilter(), and event().

pub unsafe fn set_object_name(&self, name: impl CastInto<Ref<QString>>)

This property holds the name of this object

Calls C++ function: void QObject::setObjectName(const QString& name).

C++ documentation:

This property holds the name of this object

You can find an object by name (and type) using findChild(). You can find a set of objects with findChildren().

qDebug(“MyClass::setPrecision(): (%s) invalid precision %f”,
         qPrintable(objectName()), newPrecision);

By default, this property contains an empty string.

Access functions:

QString	objectName() const
void	setObjectName(const QString &name)

Notifier signal:

void

objectNameChanged(const QString &objectName)

[see note below]

Note: This is a private signal. It can be used in signal connections but cannot be emitted by the user.

See also metaObject() and QMetaObject::className().

pub unsafe fn set_parent(&self, parent: impl CastInto<Ptr<QObject>>)

Makes the object a child of parent.

Calls C++ function: void QObject::setParent(QObject* parent).

C++ documentation:

Makes the object a child of parent.

See also parent() and children().

pub unsafe fn set_property( &self, name: *const c_char, value: impl CastInto<Ref<QVariant>> ) -> bool

Sets the value of the object's name property to value.

Calls C++ function: bool QObject::setProperty(const char* name, const QVariant& value).

C++ documentation:

Sets the value of the object’s name property to value.

If the property is defined in the class using Q_PROPERTY then true is returned on success and false otherwise. If the property is not defined using Q_PROPERTY, and therefore not listed in the meta-object, it is added as a dynamic property and false is returned.

Information about all available properties is provided through the metaObject() and dynamicPropertyNames().

Dynamic properties can be queried again using property() and can be removed by setting the property value to an invalid QVariant. Changing the value of a dynamic property causes a QDynamicPropertyChangeEvent to be sent to the object.

Note: Dynamic properties starting with "_q_" are reserved for internal purposes.

See also property(), metaObject(), dynamicPropertyNames(), and QMetaProperty::write().

pub unsafe fn signals_blocked(&self) -> bool

Returns true if signals are blocked; otherwise returns false.

Calls C++ function: bool QObject::signalsBlocked() const.

C++ documentation:

Returns true if signals are blocked; otherwise returns false.

Signals are not blocked by default.

See also blockSignals() and QSignalBlocker.

pub unsafe fn start_timer_2a( &self, interval: c_int, timer_type: TimerType ) -> c_int

Starts a timer and returns a timer identifier, or returns zero if it could not start a timer.

Calls C++ function: int QObject::startTimer(int interval, Qt::TimerType timerType = …).

C++ documentation:

Starts a timer and returns a timer identifier, or returns zero if it could not start a timer.

A timer event will occur every interval milliseconds until killTimer() is called. If interval is 0, then the timer event occurs once every time there are no more window system events to process.

The virtual timerEvent() function is called with the QTimerEvent event parameter class when a timer event occurs. Reimplement this function to get timer events.

If multiple timers are running, the QTimerEvent::timerId() can be used to find out which timer was activated.

Example:

class MyObject : public QObject
{
      Q_OBJECT
public:
      MyObject(QObject *parent = 0);
protected:
      void timerEvent(QTimerEvent *event);
};
MyObject::MyObject(QObject *parent)
      : QObject(parent)
{
      startTimer(50);     // 50-millisecond timer
      startTimer(1000);   // 1-second timer
      startTimer(60000);  // 1-minute timer
      using namespace std::chrono;
      startTimer(milliseconds(50));
      startTimer(seconds(1));
      startTimer(minutes(1));
      // since C++14 we can use std::chrono::duration literals, e.g.:
      startTimer(100ms);
      startTimer(5s);
      startTimer(2min);
      startTimer(1h);
}
void MyObject::timerEvent(QTimerEvent *event)
{
      qDebug() << “Timer ID:” << event->timerId();
}

Note that QTimer's accuracy depends on the underlying operating system and hardware. The timerType argument allows you to customize the accuracy of the timer. See Qt::TimerType for information on the different timer types. Most platforms support an accuracy of 20 milliseconds; some provide more. If Qt is unable to deliver the requested number of timer events, it will silently discard some.

The QTimer class provides a high-level programming interface with single-shot timers and timer signals instead of events. There is also a QBasicTimer class that is more lightweight than QTimer and less clumsy than using timer IDs directly.

See also timerEvent(), killTimer(), and QTimer::singleShot().

pub unsafe fn start_timer_1a(&self, interval: c_int) -> c_int

Starts a timer and returns a timer identifier, or returns zero if it could not start a timer.

Calls C++ function: int QObject::startTimer(int interval).

C++ documentation:

Starts a timer and returns a timer identifier, or returns zero if it could not start a timer.

A timer event will occur every interval milliseconds until killTimer() is called. If interval is 0, then the timer event occurs once every time there are no more window system events to process.

The virtual timerEvent() function is called with the QTimerEvent event parameter class when a timer event occurs. Reimplement this function to get timer events.

If multiple timers are running, the QTimerEvent::timerId() can be used to find out which timer was activated.

Example:

class MyObject : public QObject
{
      Q_OBJECT
public:
      MyObject(QObject *parent = 0);
protected:
      void timerEvent(QTimerEvent *event);
};
MyObject::MyObject(QObject *parent)
      : QObject(parent)
{
      startTimer(50);     // 50-millisecond timer
      startTimer(1000);   // 1-second timer
      startTimer(60000);  // 1-minute timer
      using namespace std::chrono;
      startTimer(milliseconds(50));
      startTimer(seconds(1));
      startTimer(minutes(1));
      // since C++14 we can use std::chrono::duration literals, e.g.:
      startTimer(100ms);
      startTimer(5s);
      startTimer(2min);
      startTimer(1h);
}
void MyObject::timerEvent(QTimerEvent *event)
{
      qDebug() << “Timer ID:” << event->timerId();
}

Note that QTimer's accuracy depends on the underlying operating system and hardware. The timerType argument allows you to customize the accuracy of the timer. See Qt::TimerType for information on the different timer types. Most platforms support an accuracy of 20 milliseconds; some provide more. If Qt is unable to deliver the requested number of timer events, it will silently discard some.

The QTimer class provides a high-level programming interface with single-shot timers and timer signals instead of events. There is also a QBasicTimer class that is more lightweight than QTimer and less clumsy than using timer IDs directly.

See also timerEvent(), killTimer(), and QTimer::singleShot().

pub unsafe fn thread(&self) -> QPtr<QThread>

Returns the thread in which the object lives.

Calls C++ function: QThread* QObject::thread() const.

C++ documentation:

Returns the thread in which the object lives.

See also moveToThread().

Trait Implementations

impl CppDeletable for QTemporaryFile

unsafe fn delete(&self)

Destroys the temporary file object, the file is automatically closed if necessary and if in auto remove mode it will automatically delete the file.

Calls C++ function: virtual [destructor] void QTemporaryFile::~QTemporaryFile().

C++ documentation:

Destroys the temporary file object, the file is automatically closed if necessary and if in auto remove mode it will automatically delete the file.

See also autoRemove().

impl Deref for QTemporaryFile

fn deref(&self) -> &QFile

Calls C++ function: QFile* static_cast<QFile*>(QTemporaryFile* ptr).

type Target = QFile

The resulting type after dereferencing.

impl DynamicCast<QTemporaryFile> for QFile

unsafe fn dynamic_cast(ptr: Ptr<QFile>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* dynamic_cast<QTemporaryFile*>(QFile* ptr).

impl DynamicCast<QTemporaryFile> for QFileDevice

unsafe fn dynamic_cast(ptr: Ptr<QFileDevice>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* dynamic_cast<QTemporaryFile*>(QFileDevice* ptr).

impl DynamicCast<QTemporaryFile> for QIODevice

unsafe fn dynamic_cast(ptr: Ptr<QIODevice>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* dynamic_cast<QTemporaryFile*>(QIODevice* ptr).

impl DynamicCast<QTemporaryFile> for QObject

unsafe fn dynamic_cast(ptr: Ptr<QObject>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* dynamic_cast<QTemporaryFile*>(QObject* ptr).

impl StaticDowncast<QTemporaryFile> for QFile

unsafe fn static_downcast(ptr: Ptr<QFile>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* static_cast<QTemporaryFile*>(QFile* ptr).

impl StaticDowncast<QTemporaryFile> for QFileDevice

unsafe fn static_downcast(ptr: Ptr<QFileDevice>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* static_cast<QTemporaryFile*>(QFileDevice* ptr).

impl StaticDowncast<QTemporaryFile> for QIODevice

unsafe fn static_downcast(ptr: Ptr<QIODevice>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* static_cast<QTemporaryFile*>(QIODevice* ptr).

impl StaticDowncast<QTemporaryFile> for QObject

unsafe fn static_downcast(ptr: Ptr<QObject>) -> Ptr<QTemporaryFile>

Calls C++ function: QTemporaryFile* static_cast<QTemporaryFile*>(QObject* ptr).

impl StaticUpcast<QFile> for QTemporaryFile

unsafe fn static_upcast(ptr: Ptr<QTemporaryFile>) -> Ptr<QFile>

Calls C++ function: QFile* static_cast<QFile*>(QTemporaryFile* ptr).

impl StaticUpcast<QFileDevice> for QTemporaryFile

unsafe fn static_upcast(ptr: Ptr<QTemporaryFile>) -> Ptr<QFileDevice>

Calls C++ function: QFileDevice* static_cast<QFileDevice*>(QTemporaryFile* ptr).

impl StaticUpcast<QIODevice> for QTemporaryFile

unsafe fn static_upcast(ptr: Ptr<QTemporaryFile>) -> Ptr<QIODevice>

Calls C++ function: QIODevice* static_cast<QIODevice*>(QTemporaryFile* ptr).

impl StaticUpcast<QObject> for QTemporaryFile

unsafe fn static_upcast(ptr: Ptr<QTemporaryFile>) -> Ptr<QObject>

Calls C++ function: QObject* static_cast<QObject*>(QTemporaryFile* ptr).