Struct druid::widget::AspectRatioBox

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

A widget that preserves the aspect ratio given to it.

If given a child, this widget forces the child to have a width and height that preserves the aspect ratio.

If not given a child, The box will try to size itself as large or small as possible to preserve the aspect ratio.

Implementations

impl<T> AspectRatioBox<T>

pub fn new(child: impl Widget<T> + 'static, ratio: f64) -> Self

Create container with a child and aspect ratio.

The aspect ratio is defined as width / height.

If aspect ratio <= 0.0, the ratio will be set to 1.0

Examples found in repository

examples/layout.rs (line 69)

fn build_app() -> impl Widget<u32> {
    // Usually we put all the widgets in one big tree using builder-style
    // methods. Sometimes we split them up in declarations to increase
    // readability. In this case we also have some recurring elements,
    // we add those in a loop later on.
    let mut col = Flex::column().with_child(
        // The `Flex`'s first child is another Flex! In this case it is
        // a row.
        Flex::row()
            // The row has its own children.
            .with_child(
                Label::new("One")
                    .fix_width(60.0)
                    .background(Color::rgb8(0x77, 0x77, 0))
                    .border(Color::WHITE, 3.0)
                    .center(),
            )
            // Spacing element that will fill all available space in
            // between label and a button. Notice that weight is non-zero.
            // We could have achieved a similar result with expanding the
            // width and setting the main-axis-allignment to SpaceBetween.
            .with_flex_spacer(1.0)
            .with_child(Button::new("Two").padding(20.))
            // After we added all the children, we can set some more
            // values using builder-style methods. Since these methods
            // dont return the original `Flex` but a SizedBox and Container
            // respectively, we have to put these at the end.
            .fix_height(100.0)
            //turquoise
            .background(Color::rgb8(0, 0x77, 0x88)),
    );

    for i in 0..5 {
        // Give a larger weight to one of the buttons for it to
        // occupy more space.
        let weight = if i == 2 { 3.0 } else { 1.0 };
        // call `expand_height` to force the buttons to use all their provided flex
        col.add_flex_child(Button::new(format!("Button #{i}")).expand_height(), weight);
    }

    // aspect ratio box
    let aspect_ratio_label = Label::new("This is an aspect-ratio box. Notice how the text will overflow if the box becomes too small.")
        .with_text_color(Color::BLACK)
        .with_line_break_mode(LineBreaking::WordWrap)
        .center();
    let aspect_ratio_box = AspectRatioBox::new(aspect_ratio_label, 4.0)
        .border(Color::BLACK, 1.0)
        .background(Color::WHITE);
    col.add_flex_child(aspect_ratio_box.center(), 1.0);

    // This method asks Druid to draw colored rectangles around our widgets,
    // so we can visually inspect their layout rectangles.
    col.debug_paint_layout()
}

pub fn set_ratio(&mut self, ratio: f64)

Set the ratio of the box.

The ratio has to be a value between 0 and f64::MAX, excluding 0. It will be clamped to those values if they exceed the bounds. If the ratio is 0, then the ratio will become 1.

Trait Implementations

impl<T: Data> Widget<T> for AspectRatioBox<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<'_, '_>, 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.