Struct druid::widget::ClipBox

pub struct ClipBox<T, W> { /* private fields */ }

A widget exposing a rectangular view into its child, which can be used as a building block for widgets that scroll their child.

Implementations

impl<T, W> ClipBox<T, W>

pub fn constrain_vertical(self, constrain: bool) -> Self

Builder-style method for deciding whether to constrain the child vertically.

The default is false.

This setting affects how a ClipBox lays out its child.

• When it is false (the default), the child does not receive any upper bound on its height: the idea is that the child can be as tall as it wants, and the viewport will somehow get moved around to see all of it.
• When it is true, the viewport’s maximum height will be passed down as an upper bound on the height of the child, and the viewport will set its own height to be the same as its child’s height.

pub fn constrain_horizontal(self, constrain: bool) -> Self

Builder-style method for deciding whether to constrain the child horizontally.

The default is false. See constrain_vertical for more details.

pub fn content_must_fill(self, must_fill: bool) -> Self

Builder-style method to set whether the child must fill the view.

If false (the default) there is no minimum constraint on the child’s size. If true, the child is passed the same minimum constraints as the ClipBox.

pub fn child(&self) -> &W

Returns a reference to the child widget.

pub fn child_mut(&mut self) -> &mut W

Returns a mutable reference to the child widget.

pub fn viewport(&self) -> Viewport

Returns a the viewport describing this ClipBox’s position.

pub fn viewport_origin(&self) -> Point

Returns the origin of the viewport rectangle.

pub fn viewport_size(&self) -> Size

Returns the size of the rectangular viewport into the child widget. To get the position of the viewport, see viewport_origin.

pub fn content_size(&self) -> Size

Returns the size of the child widget.

pub fn set_constrain_horizontal(&mut self, constrain: bool)

Set whether to constrain the child horizontally.

See constrain_vertical for more details.

pub fn set_constrain_vertical(&mut self, constrain: bool)

Set whether to constrain the child vertically.

See constrain_vertical for more details.

pub fn set_content_must_fill(&mut self, must_fill: bool)

Set whether the child’s size must be greater than or equal the size of the ClipBox.

See content_must_fill for more details.

impl<T, W: Widget<T>> ClipBox<T, W>

pub fn managed(child: W) -> Self

Creates a new ClipBox wrapping child.

This method should only be used when creating your own widget, which uses ClipBox internally.

ClipBox will forward SCROLL_TO_VIEW notifications to its parent unchanged. In this case the parent has to handle said notification itself. By default the ClipBox will filter out SCROLL_TO_VIEW notifications which refer to areas not visible.

pub fn unmanaged(child: W) -> Self

Creates a new unmanaged ClipBox wrapping child.

This method should be used when you are using ClipBox in the widget tree directly.

pub fn pan_by<C: ChangeCtx>(&mut self, ctx: &mut C, delta: Vec2) -> bool

Pans by delta units.

Returns true if the scroll offset has changed.

pub fn pan_to_visible<C: ChangeCtx>(&mut self, ctx: &mut C, region: Rect) -> bool

Pans the minimal distance to show the region.

If the target region is larger than the viewport, we will display the portion that fits, prioritizing the portion closest to the origin.

pub fn pan_to_on_axis<C: ChangeCtx>( &mut self, ctx: &mut C, axis: Axis, position: f64 ) -> bool

Pan to this position on a particular axis.

Returns true if the scroll offset has changed.

pub fn with_port<C: ChangeCtx, F: FnOnce(&mut C, &mut Viewport)>( &mut self, ctx: &mut C, f: F ) -> bool

Modify the ClipBox’s viewport rectangle with a closure.

The provided callback function can modify its argument, and when it is done then this ClipBox will be modified to have the new viewport rectangle.

Trait Implementations

impl<T: Data, W: Widget<T>> Widget<T> for ClipBox<T, W>

fn event( &mut self, ctx: &mut EventCtx<'_, '_>, event: &Event, data: &mut T, env: &Env )

Handle an event.

fn lifecycle( &mut self, ctx: &mut LifeCycleCtx<'_, '_>, event: &LifeCycle, data: &T, env: &Env )

Handle a life cycle notification.

fn update( &mut self, ctx: &mut UpdateCtx<'_, '_>, _old_data: &T, data: &T, env: &Env )

Update the widget’s appearance in response to a change in the app’s Data or Env.

fn layout( &mut self, ctx: &mut LayoutCtx<'_, '_>, bc: &BoxConstraints, data: &T, env: &Env ) -> Size

Compute layout.

fn paint(&mut self, ctx: &mut PaintCtx<'_, '_, '_>, data: &T, env: &Env)

Paint the widget appearance.

fn compute_max_intrinsic( &mut self, axis: Axis, ctx: &mut LayoutCtx<'_, '_>, bc: &BoxConstraints, data: &T, env: &Env ) -> f64

Computes max intrinsic/preferred dimension of a widget on the provided axis.