Struct rute::auto::object::Object

pub struct Object<'a> { /* private fields */ }

Notice these docs are heavy WIP and not very relevent yet

QObject is the heart of the Qt Object Model . The central feature in this model is a very powerful mechanism for seamless object communication called signals and slots . You can connect a signal to a slot with connect() and destroy the connection with disconnect(). To avoid never ending notification loops you can temporarily block signals with blockSignals(). The protected functions connectNotify() and disconnectNotify() make it possible to track connections.

QObjects organize themselves in object trees . When you create a QObject with another object as parent, the object will automatically add itself to the parent’s children() list. The parent takes ownership of the object; i.e., it will automatically delete its children in its destructor. You can look for an object by name and optionally type using findChild() or findChildren().

Every object has an objectName() and its class name can be found via the corresponding metaObject() (see QMetaObject::className()). You can determine whether the object’s class inherits another class in the QObject inheritance hierarchy by using the inherits() function.

When an object is deleted, it emits a destroyed() signal. You can catch this signal to avoid dangling references to QObjects.

QObjects can receive events through event() and filter the events of other objects. See installEventFilter() and eventFilter() for details. A convenience handler, childEvent(), can be reimplemented to catch child events.

Last but not least, QObject provides the basic timer support in Qt; see QTimer for high-level support for timers.

Notice that the Q_OBJECT macro is mandatory for any object that implements signals, slots or properties. You also need to run the Meta Object Compiler on the source file. We strongly recommend the use of this macro in all subclasses of QObject regardless of whether or not they actually use signals, slots and properties, since failure to do so may lead certain functions to exhibit strange behavior.

All Qt widgets inherit QObject. The convenience function isWidgetType() returns whether an object is actually a widget. It is much faster than qobject_cast <QWidget *>( obj ) or obj -> inherits (“QWidget”).

Some QObject functions, e.g. children(), return a QObjectList. QObjectList is a typedef for QList<QObject *>.

Thread Affinity

A QObject instance is said to have a thread affinity , or that it lives in a certain thread. When a QObject receives a queued signal or a posted event , the slot or event handler will run in the thread that the object lives in.

Note: If a QObject has no thread affinity (that is, if thread() returns zero), or if it lives in a thread that has no running event loop, then it cannot receive queued signals or posted events.

By default, a QObject lives in the thread in which it is created. An object’s thread affinity can be queried using thread() and changed using moveToThread().

All QObjects must live in the same thread as their parent. Consequently:

• setParent() will fail if the two QObjects involved live in different threads.
• When a QObject is moved to another thread, all its children will be automatically moved too.
• moveToThread() will fail if the QObject has a parent.
• If QObjects are created within QThread::run(), they cannot become children of the QThread object because the QThread does not live in the thread that calls QThread::run().

Note: A QObject’s member variables do not automatically become its children. The parent-child relationship must be set by either passing a pointer to the child’s constructor , or by calling setParent(). Without this step, the object’s member variables will remain in the old thread when moveToThread() is called.

No Copy Constructor or Assignment Operator

QObject has neither a copy constructor nor an assignment operator. This is by design. Actually, they are declared, but in a private section with the macro Q_DISABLE_COPY(). In fact, all Qt classes derived from QObject (direct or indirect) use this macro to declare their copy constructor and assignment operator to be private. The reasoning is found in the discussion on Identity vs Value on the Qt Object Model page.

The main consequence is that you should use pointers to QObject (or to your QObject subclass) where you might otherwise be tempted to use your QObject subclass as a value. For example, without a copy constructor, you can’t use a subclass of QObject as the value to be stored in one of the container classes. You must store pointers.

Auto-Connection

Qt’s meta-object system provides a mechanism to automatically connect signals and slots between QObject subclasses and their children. As long as objects are defined with suitable object names, and slots follow a simple naming convention, this connection can be performed at run-time by the QMetaObject::connectSlotsByName() function.

uic generates code that invokes this function to enable auto-connection to be performed between widgets on forms created with Qt Designer . More information about using auto-connection with Qt Designer is given in the Using a Designer UI File in Your Application section of the Qt Designer manual.

Dynamic Properties

From Qt 4.2, dynamic properties can be added to and removed from QObject instances at run-time. Dynamic properties do not need to be declared at compile-time, yet they provide the same advantages as static properties and are manipulated using the same API - using property() to read them and setProperty() to write them.

From Qt 4.3, dynamic properties are supported by Qt Designer

and both standard Qt widgets and user-created forms can be given dynamic properties.

Internationalization (I18n)

All QObject subclasses support Qt’s translation features, making it possible to translate an application’s user interface into different languages.

To make user-visible text translatable, it must be wrapped in calls to the tr() function. This is explained in detail in the Writing Source Code for Translation document.

See also: [MetaObject] [Pointer] [ObjectCleanupHandler] [q_disable_copy()] See also: {Object Trees & Ownership}

Licence

The documentation is an adoption of the original Qt Documentation and provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation.

Implementations

impl<'a> Object<'a>

pub fn new() -> Object<'a>

pub fn object_name(&self) -> String

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:

See also: [install_event_filter()] [timer_event()] [CoreApplication::send_event] [CoreApplication::post_event]

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:

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: [install_event_filter()]

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:

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: [install_event_filter()]

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

By default, this property contains an empty string.

See also: [meta_object()] [MetaObject::class_name]

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

See also: Object::object_name()

pub fn set_object_name(&self, name: &str) -> &Self

pub fn is_widget_type(&self) -> bool

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 fn is_window_type(&self) -> bool

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 fn signals_blocked(&self) -> bool

Returns true if signals are blocked; otherwise returns false.

Signals are not blocked by default.

See also: [block_signals()] [SignalBlocker]

pub 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.

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: [signals_blocked()] [SignalBlocker]

pub fn start_timer(&self, interval: i32, timer_type: TimerType) -> i32

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:

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: [timer_event()] [kill_timer()] [Timer::single_shot]

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

A timer event will occur every time interval until killTimer() is called. If time is equal to std::chrono::duration::zero() , 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:

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: [timer_event()] [kill_timer()] [Timer::single_shot]

pub fn start_timer_2(&self, time: u32, timer_type: TimerType) -> i32

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:

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: [timer_event()] [kill_timer()] [Timer::single_shot]

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

A timer event will occur every time interval until killTimer() is called. If time is equal to std::chrono::duration::zero() , 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:

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: [timer_event()] [kill_timer()] [Timer::single_shot]

pub fn kill_timer(&self, id: i32) -> &Self

Kills the timer with timer identifier, id.

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

See also: [timer_event()] [start_timer()]

pub fn set_parent<O: ObjectTrait<'a>>(&self, parent: &O) -> &Self

Makes the object a child of parent.

See also: [parent()] [children()]

pub fn install_event_filter<O: ObjectTrait<'a>>(&self, filter_obj: &O) -> &Self

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

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:

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

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: [remove_event_filter()] [event_filter()] [event()]

pub fn dump_object_tree(&self) -> &Self

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: [install_event_filter()] [event_filter()] [event()]

Overloads Dumps a tree of children to the debug output.

See also: [dump_object_info()]

Dumps a tree of children to the debug output.

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

See also: [dump_object_info()]

pub fn dump_object_info(&self) -> &Self

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

See also: [dump_object_tree()]

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: [dump_object_tree()]

pub fn dump_object_tree_2(&self) -> &Self

Overloads Dumps a tree of children to the debug output.

See also: [dump_object_info()]

Dumps a tree of children to the debug output.

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

See also: [dump_object_info()]

pub fn dump_object_info_2(&self) -> &Self

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

See also: [dump_object_tree()]

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: [dump_object_tree()]

pub fn parent(&self) -> Option<Object<'_>>

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 are reserved for internal purposes.

See also: [property()] [meta_object()] [dynamic_property_names()] [MetaProperty::write]

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: [set_property()] [Variant::is_valid] [meta_object()] [dynamic_property_names()]

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

See also: Object::object_name()

Returns a pointer to the parent object.

See also: [children()]

pub fn delete_later(&self) -> &Self

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()] [Pointer]

pub fn set_custom_event_ud<F, T>(&self, data: &'a T, func: F) -> &Selfwhere
    F: Fn(&T, &Event<'_>) + 'a,
    T: 'a,

Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0. The pointer is valid only during the execution of the slot that calls this function from this object’s thread context.

The pointer returned by this function becomes invalid if the sender is destroyed, or if the slot is disconnected from the sender’s signal.

Warning: This function violates the object-oriented principle of modularity. However, getting access to the sender might be useful when many signals are connected to a single slot.

Warning: As mentioned above, the return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object’s thread. Do not use this function in this type of scenario.

See also: [sender_signal_index()]

Returns the meta-method index of the signal that called the currently executing slot, which is a member of the class returned by sender(). If called outside of a slot activated by a signal, -1 is returned.

For signals with default parameters, this function will always return the index with all parameters, regardless of which was used with connect(). For example, the signal destroyed(QObject *obj = 0) will have two different indexes (with and without the parameter), but this function will always return the index with a parameter. This does not apply when overloading signals with different parameters.

Warning: This function violates the object-oriented principle of modularity. However, getting access to the signal index might be useful when many signals are connected to a single slot.

Warning: The return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object’s thread. Do not use this function in this type of scenario.

See also: [sender()] [MetaObject::index_of_signal] [MetaObject::method]

Returns the meta-method index of the signal that called the currently executing slot, which is a member of the class returned by sender(). If called outside of a slot activated by a signal, -1 is returned.

For signals with default parameters, this function will always return the index with all parameters, regardless of which was used with connect(). For example, the signal destroyed(QObject *obj = 0) will have two different indexes (with and without the parameter), but this function will always return the index with a parameter. This does not apply when overloading signals with different parameters.

Warning: This function violates the object-oriented principle of modularity. However, getting access to the signal index might be useful when many signals are connected to a single slot.

Warning: The return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object’s thread. Do not use this function in this type of scenario.

See also: [sender()] [MetaObject::index_of_signal] [MetaObject::method]

Returns true if the signal is connected to at least one receiver, otherwise returns false.

signal must be a signal member of this object, otherwise the behaviour is undefined.

As the code snippet above illustrates, you can use this function to avoid emitting a signal that nobody listens to.

Warning: This function violates the object-oriented principle of modularity. However, it might be useful when you need to perform expensive initialization only if something is connected to a signal.

This event handler can be reimplemented in a subclass to receive custom events. Custom events are user-defined events with a type value at least as large as the QEvent::User item of the QEvent::Type enum, and is typically a QEvent subclass. The event is passed in the event parameter.

See also: [event()] Event

pub fn set_custom_event<F>(&self, func: F) -> &Selfwhere
    F: Fn(&Event<'_>) + 'a,

Trait Implementations

impl<'a> Clone for Object<'a>

fn clone(&self) -> Object<'a>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> ObjectTrait<'a> for Object<'a>