Struct qt_gui::QTextLayout

source ·

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

Expand description

The QTextLayout class is used to lay out and render text.

C++ class: QTextLayout.

C++ documentation:

The QTextLayout class is used to lay out and render text.

It offers many features expected from a modern text layout engine, including Unicode compliant rendering, line breaking and handling of cursor positioning. It can also produce and render device independent layout, something that is important for WYSIWYG applications.

The class has a rather low level API and unless you intend to implement your own text rendering for some specialized widget, you probably won't need to use it directly.

QTextLayout can be used with both plain and rich text.

QTextLayout can be used to create a sequence of QTextLine instances with given widths and can position them independently on the screen. Once the layout is done, these lines can be drawn on a paint device.

The text to be laid out can be provided in the constructor or set with setText().

The layout can be seen as a sequence of QTextLine objects; use createLine() to create a QTextLine instance, and lineAt() or lineForTextPosition() to retrieve created lines.

Here is a code snippet that demonstrates the layout phase:

int leading = fontMetrics.leading();
qreal height = 0;
textLayout.setCacheEnabled(true);
textLayout.beginLayout();
while (1) {
      QTextLine line = textLayout.createLine();
      if (!line.isValid())
          break;
      line.setLineWidth(lineWidth);
      height += leading;
      line.setPosition(QPointF(0, height));
      height += line.height();
}
textLayout.endLayout();

The text can then be rendered by calling the layout's draw() function:

QPainter painter(this);
textLayout.draw(&painter, QPoint(0, 0));

For a given position in the text you can find a valid cursor position with isValidCursorPosition(), nextCursorPosition(), and previousCursorPosition().

The QTextLayout itself can be positioned with setPosition(); it has a boundingRect(), and a minimumWidth() and a maximumWidth().

Struct qt_gui::QTextLayout

Implementations§

impl QTextLayout

pub unsafe fn additional_formats(&self) -> CppBox<QListOfFormatRange>

pub unsafe fn begin_layout(&self)

pub unsafe fn bounding_rect(&self) -> CppBox<QRectF>

pub unsafe fn cache_enabled(&self) -> bool

pub unsafe fn clear_additional_formats(&self)

pub unsafe fn clear_formats(&self)

pub unsafe fn clear_layout(&self)

pub unsafe fn create_line(&self) -> CppBox<QTextLine>

pub unsafe fn cursor_move_style(&self) -> CursorMoveStyle

pub unsafe fn draw_4a( &self, p: impl CastInto<Ptr<QPainter>>, pos: impl CastInto<Ref<QPointF>>, selections: impl CastInto<Ref<QVectorOfFormatRange>>, clip: impl CastInto<Ref<QRectF>> )

pub unsafe fn draw_3a( &self, p: impl CastInto<Ptr<QPainter>>, pos: impl CastInto<Ref<QPointF>>, selections: impl CastInto<Ref<QVectorOfFormatRange>> )

pub unsafe fn draw_2a( &self, p: impl CastInto<Ptr<QPainter>>, pos: impl CastInto<Ref<QPointF>> )

pub unsafe fn draw_cursor_3a( &self, p: impl CastInto<Ptr<QPainter>>, pos: impl CastInto<Ref<QPointF>>, cursor_position: c_int )

pub unsafe fn draw_cursor_4a( &self, p: impl CastInto<Ptr<QPainter>>, pos: impl CastInto<Ref<QPointF>>, cursor_position: c_int, width: c_int )

pub unsafe fn end_layout(&self)

pub unsafe fn font(&self) -> CppBox<QFont>

pub unsafe fn formats(&self) -> CppBox<QVectorOfFormatRange>

pub unsafe fn glyph_runs_2a( &self, from: c_int, length: c_int ) -> CppBox<QListOfQGlyphRun>

pub unsafe fn glyph_runs_1a(&self, from: c_int) -> CppBox<QListOfQGlyphRun>

pub unsafe fn glyph_runs_0a(&self) -> CppBox<QListOfQGlyphRun>

pub unsafe fn is_valid_cursor_position(&self, pos: c_int) -> bool

pub unsafe fn left_cursor_position(&self, old_pos: c_int) -> c_int

pub unsafe fn line_at(&self, i: c_int) -> CppBox<QTextLine>

pub unsafe fn line_count(&self) -> c_int

pub unsafe fn line_for_text_position(&self, pos: c_int) -> CppBox<QTextLine>

pub unsafe fn maximum_width(&self) -> c_double

pub unsafe fn minimum_width(&self) -> c_double

pub unsafe fn new() -> CppBox<QTextLayout>

pub unsafe fn from_q_string( text: impl CastInto<Ref<QString>> ) -> CppBox<QTextLayout>

pub unsafe fn from_q_string_q_font_q_paint_device( text: impl CastInto<Ref<QString>>, font: impl CastInto<Ref<QFont>>, paintdevice: impl CastInto<Ptr<QPaintDevice>> ) -> CppBox<QTextLayout>

pub unsafe fn from_q_text_block( b: impl CastInto<Ref<QTextBlock>> ) -> CppBox<QTextLayout>

pub unsafe fn from_q_string_q_font( text: impl CastInto<Ref<QString>>, font: impl CastInto<Ref<QFont>> ) -> CppBox<QTextLayout>

pub unsafe fn next_cursor_position_2a( &self, old_pos: c_int, mode: CursorMode ) -> c_int

pub unsafe fn next_cursor_position_1a(&self, old_pos: c_int) -> c_int

pub unsafe fn position(&self) -> CppBox<QPointF>

pub unsafe fn preedit_area_position(&self) -> c_int

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

pub unsafe fn previous_cursor_position_2a( &self, old_pos: c_int, mode: CursorMode ) -> c_int

pub unsafe fn previous_cursor_position_1a(&self, old_pos: c_int) -> c_int

pub unsafe fn right_cursor_position(&self, old_pos: c_int) -> c_int

pub unsafe fn set_additional_formats( &self, overrides: impl CastInto<Ref<QListOfFormatRange>> )

pub unsafe fn set_cache_enabled(&self, enable: bool)

pub unsafe fn set_cursor_move_style(&self, style: CursorMoveStyle)

pub unsafe fn set_flags(&self, flags: c_int)

pub unsafe fn set_font(&self, f: impl CastInto<Ref<QFont>>)

pub unsafe fn set_formats( &self, overrides: impl CastInto<Ref<QVectorOfFormatRange>> )

pub unsafe fn set_position(&self, p: impl CastInto<Ref<QPointF>>)

pub unsafe fn set_preedit_area( &self, position: c_int, text: impl CastInto<Ref<QString>> )

pub unsafe fn set_raw_font(&self, raw_font: impl CastInto<Ref<QRawFont>>)

pub unsafe fn set_text(&self, string: impl CastInto<Ref<QString>>)

pub unsafe fn set_text_option(&self, option: impl CastInto<Ref<QTextOption>>)

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

pub unsafe fn text_option(&self) -> Ref<QTextOption>

Trait Implementations§

impl CppDeletable for QTextLayout

unsafe fn delete(&self)

Auto Trait Implementations§

impl RefUnwindSafe for QTextLayout

impl Send for QTextLayout

impl Sync for QTextLayout

impl Unpin for QTextLayout

impl UnwindSafe for QTextLayout

Blanket Implementations§

impl<T> Any for Twhere T: 'static + ?Sized,

fn type_id(&self) -> TypeId

impl<T> Borrow<T> for Twhere T: ?Sized,

fn borrow(&self) -> &T

impl<T> BorrowMut<T> for Twhere T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

impl<T, U> CastInto<U> for Twhere U: CastFrom<T>,

unsafe fn cast_into(self) -> U

impl<T> From<T> for T

fn from(t: T) -> T

impl<T, U> Into<U> for Twhere U: From<T>,

fn into(self) -> U

impl<T> StaticUpcast<T> for T

unsafe fn static_upcast(ptr: Ptr<T>) -> Ptr<T>

impl<T> Any for T
where T: 'static + ?Sized,

impl<T> Borrow<T> for T
where T: ?Sized,

impl<T> BorrowMut<T> for T
where T: ?Sized,

impl<T, U> CastInto<U> for T
where U: CastFrom<T>,

impl<T, U> Into<U> for T
where U: From<T>,

impl<T, U> TryFrom<U> for T
where U: Into<T>,

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,