Struct ZStack

pub struct ZStack<T> { /* private fields */ }

A container that stacks its children on top of each other.

The container has a baselayer which has the lowest z-index and determines the size of the container.

Implementations

impl<T: Data> ZStack<T>

pub fn new(base_layer: impl Widget<T> + 'static) -> Self

Creates a new ZStack with a baselayer.

The baselayer is used by the ZStack to determine its own size.

Examples found in repository

examples/z_stack.rs (lines 46-54)

fn build_root_widget() -> impl Widget<State> {
    ZStack::new(
        Button::from_label(Label::dynamic(|state: &State, _| {
            format!(
                "Very large button with text! Count up (currently {})",
                state.counter
            )
        }))
        .on_click(|_, state: &mut State, _| state.counter += 1),
    )
    .with_child(
        Button::new("Reset").on_click(|_, state: &mut State, _| state.counter = 0),
        Vec2::new(1.0, 1.0),
        Vec2::ZERO,
        UnitPoint::LEFT,
        Vec2::new(10.0, 0.0),
    )
}

pub fn with_child( self, child: impl Widget<T> + 'static, relative_size: Vec2, absolute_size: Vec2, position: UnitPoint, offset: Vec2, ) -> Self

Builder-style method to add a new child to the Z-Stack.

The child is added directly above the base layer.

relative_size is the space the child is allowed to take up relative to its parent. The values are between 0 and 1. absolute_size is a fixed amount of pixels added to relative_size.

position is the alignment of the child inside the remaining space of its parent.

offset is a fixed amount of pixels added to position.

Examples found in repository

examples/z_stack.rs (lines 55-61)

fn build_root_widget() -> impl Widget<State> {
    ZStack::new(
        Button::from_label(Label::dynamic(|state: &State, _| {
            format!(
                "Very large button with text! Count up (currently {})",
                state.counter
            )
        }))
        .on_click(|_, state: &mut State, _| state.counter += 1),
    )
    .with_child(
        Button::new("Reset").on_click(|_, state: &mut State, _| state.counter = 0),
        Vec2::new(1.0, 1.0),
        Vec2::ZERO,
        UnitPoint::LEFT,
        Vec2::new(10.0, 0.0),
    )
}

pub fn with_centered_child(self, child: impl Widget<T> + 'static) -> Self

Builder-style method to add a new child to the Z-Stack.

The child is added directly above the base layer, is positioned in the center and has no size constraints.

pub fn with_aligned_child( self, child: impl Widget<T> + 'static, alignment: UnitPoint, ) -> Self

Builder-style method to add a new child to the Z-Stack.

The child is added directly above the base layer, uses the given alignment and has no size constraints.

Trait Implementations

impl<T: Data> Widget<T> for ZStack<T>

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<'_, '_>, _: &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.