Trait gtk4::prelude::LayoutManagerExt

pub trait LayoutManagerExt: 'static {
    fn allocate(
        &self,
        widget: &impl IsA<Widget>,
        width: i32,
        height: i32,
        baseline: i32
    );
    fn layout_child(&self, child: &impl IsA<Widget>) -> LayoutChild;
    fn request_mode(&self) -> SizeRequestMode;
    fn widget(&self) -> Option<Widget>;
    fn layout_changed(&self);
    fn measure(
        &self,
        widget: &impl IsA<Widget>,
        orientation: Orientation,
        for_size: i32
    ) -> (i32, i32, i32, i32);
}

Trait containing all LayoutManager methods.

Implementors

BinLayout, BoxLayout, CenterLayout, ConstraintLayout, FixedLayout, GridLayout, LayoutManager, OverlayLayout

Required Methods

fn allocate(
    &self,
    widget: &impl IsA<Widget>,
    width: i32,
    height: i32,
    baseline: i32
)

Assigns the given @width, @height, and @baseline to a @widget, and computes the position and sizes of the children of the @widget using the layout management policy of @self.

widget

the Widget using @self

width

the new width of the @widget

height

the new height of the @widget

baseline

the baseline position of the @widget, or -1

fn layout_child(&self, child: &impl IsA<Widget>) -> LayoutChild

Retrieves a LayoutChild instance for the LayoutManager, creating one if necessary.

The @child widget must be a child of the widget using @self.

The LayoutChild instance is owned by the LayoutManager, and is guaranteed to exist as long as @child is a child of the Widget using the given LayoutManager.

child

a Widget

Returns

a LayoutChild

fn request_mode(&self) -> SizeRequestMode

Retrieves the request mode of @self.

Returns

a SizeRequestMode

fn widget(&self) -> Option<Widget>

Retrieves the Widget using the given LayoutManager.

Returns

a Widget

fn layout_changed(&self)

Queues a resize on the Widget using @self, if any.

This function should be called by subclasses of LayoutManager in response to changes to their layout management policies.

fn measure(
    &self,
    widget: &impl IsA<Widget>,
    orientation: Orientation,
    for_size: i32
) -> (i32, i32, i32, i32)

Measures the size of the @widget using @self, for the given @orientation and size.

See the Widget documentation on layout management for more details.

widget

the Widget using @self

orientation

the orientation to measure

for_size

Size for the opposite of @orientation; for instance, if the @orientation is Orientation::Horizontal, this is the height of the widget; if the @orientation is Orientation::Vertical, this is the width of the widget. This allows to measure the height for the given width, and the width for the given height. Use -1 if the size is not known

Returns

minimum

the minimum size for the given size and orientation

natural

the natural, or preferred size for the given size and orientation

minimum_baseline

the baseline position for the minimum size

natural_baseline

the baseline position for the natural size

Implementors

impl<O: IsA<LayoutManager>> LayoutManagerExt for O