Arkham | Stacks

Stack Components

Stacks are a convenient layout component available through the ViewContext. They allow a number of components to be easily positioned next to each other.

Stacks can be either horizontal or vertical.

To use a stack initialize it from the context and use the Stack::insert and Stack:component functions. The Stack::component function requires only a Size and not a Rect like the ViewContext. This is because the stack will automatically handle its positioning.

let size = ctx.size();
let mut stack = ctx.vertical_stack(Size::new(100, 100));
stack.component((size.width, 2), my_component);
// We can pass size here and it will be automtically 
// converted to a Rect with position (0,0).
ctx.component(size, stack);

Alignment

Stacks can also have a specified alignment. This will modify the positioning of the sub components so they align in the given direction.

Vertical stacks can have Left, Center, Right alignments Horizontal stacks can have Top, Center, Bottom alignments

let size = ctx.size();
let mut stack = ctx.vertical_stack(Size::new(100, 100));
stack.alignment(StackAlignment::Center);

Full stack example

use arkham::prelude::*;

fn main() {
    let _ = App::new(root).run();
}

fn root(ctx: &mut ViewContext) {
    let mut stack = ctx.vertical_stack((100, 100));
    for _ in 0..10 {
        stack.component((ctx.size().width, 1), list_item);
    }
    ctx.component((0, (100, 100)), stack);
}

fn list_item(ctx: &mut ViewContext) {
    let size = ctx.size();
    let mut hstack = ctx.horizontal_stack((ctx.size().width, 1));
    hstack.insert("> ");
    hstack.insert("line 1");
    ctx.component(size, hstack);
}