ScrollBoxRenderable — scrollable viewport container
A container that exposes scroll offsets and scrollable content dimensions
for its children. Use it to make a region of the UI scrollable: put the
content widget inside it, then drive scroll_x/scroll_y from input or a
scroll bar.
ScrollBoxRenderable::new() -> SelfScrolling
| Method | Effect |
|---|---|
set_scroll_x(i32) / set_scroll_y(i32) |
Set the offset (clamped ≥ 0). |
scroll_x() / scroll_y() |
Read the offsets. |
scroll_by(dx, dy) |
Adjust both offsets at once. |
set_content_size(width, height) |
Tell the box how big its content is. |
Layout
build_style() returns a flex-column style with overflow: scroll on both
axes, so a LayoutTree reserves the box’s area and scrolls its contents.
Rendering
render_self is currently a no-op: the box itself draws nothing. It
exists to carry scroll state and to clip/offset its children when the
renderer drives layout; content widgets inside it handle their own drawing
(using the box’s offsets via their own scroll setters, e.g.
TextRenderable::set_scroll_y).
Example
use cosh_tui::core::renderables::scroll_box::ScrollBoxRenderable;
let mut viewport = ScrollBoxRenderable::new();
viewport.set_content_size(100, 500); // content is 100×500
viewport.scroll_by(0, 40); // view a window starting at y=40
assert_eq!(viewport.scroll_y(), 40);