Module zng::stack

Stack layout widget, nodes and properties.

The Stack! widget is a layout panel stacks children, in Z and in a direction.

The example below declares a stack that animates between directions.

use zng::prelude::*;

let direction = var(StackDirection::top_to_bottom());
Stack! {
    direction = direction.easing(1.secs(), |t| easing::ease_out(easing::expo, t));
    spacing = 10;
    children_align = layout::Align::CENTER;

    toggle::selector = toggle::Selector::single(direction);
    children = [
        ("top_to_bottom", StackDirection::top_to_bottom()),
        ("left_to_right", StackDirection::left_to_right()),
        ("bottom_to_top", StackDirection::bottom_to_top()),
        ("right_to_left", StackDirection::right_to_left()),
        ("diagonal", StackDirection {
            place: layout::Point::bottom_right(),
            origin: layout::Point::top_left(),
            is_rtl_aware: false,
        }),
    ]
    .into_iter()
    .map(|(label, direction)| Toggle! {
        child = Text!(label);
        value::<StackDirection> = direction;
    })
    .collect::<UiVec>();
}

Note that the StackDirection is defined by two points, the stack widget resolves the place point in the previous child and the origin point in the next child and then positions the next child so that both points overlap. This enables custom layouts like partially overlapping children and the traditional horizontal and vertical stack.

Full API

See zng_wgt_stack for the full widget API.

Structs

• Stack
  W Stack layout.
• StackDirection
  Defines a placement point in the previous item and the origin point of the next.

Traits

• WidgetInfoStackExt
  Extension methods for WidgetInfo that may represent a Stack! instance.

Functions

• get_index
  P Get the child index in the parent stack.
• get_index_len
  P Get the child index and number of children.
• get_rev_index
  P Get the child index, starting from the last child at 0.
• is_even
  P If the child index is even.
• is_first
  P If the child is the first.
• is_last
  P If the child is the last.
• is_odd
  P If the child index is odd.
• lazy_sample
  Create a node that estimates the size of stack panel children.
• lazy_size
  Create a node that estimates the size of stack panel children.
• node
  Stack node.
• stack_nodes
  Basic z-stack node.
• stack_nodes_layout_by
  Basic z-stack node sized by one of the items.