SplitterHandle

Layer: atom · Path: src/atoms/splitter_handle.rs · Exports: splitter_handle::SplitterHandle

The draggable divider band between two Splitter panels. It fills its area as a drag hit-target and paints a centered hairline (token border) that fades to ring on hover/drag, setting the resize cursor. The owning Splitter organism reads the returned Response (drag delta, double-click) — the atom paints, the organism composes.

Design

• Purpose / when to use — only inside a Splitter organism, as the resize grip between panes. For a static rule use Divider.
• Anatomy — the full ui.max_rect() allocated as a click_and_drag hit-target → a centered border hairline (vline/hline) → on hover/drag/active, a ring overlay line at BORDER_FOCUS, ramped by hover_t. Sets ResizeHorizontal/ResizeVertical cursor while interacting.
• Variants / sizes / states
  • line: Axis — orientation of the visible rule: Vertical for a left/right (horizontal) split, Horizontal for a top/bottom (vertical) split.
  • .active(bool) — force the highlighted state (e.g. mid-drag, or when a neighbor is collapsed).
  • States: hover/drag highlight (cursor + ring fade), plus forced active.
• Tokens consumed — theme.border (hairline), theme.ring (highlight), core::BORDER_THIN (hairline weight), core::BORDER_FOCUS (highlight weight), core::hover_t (fade).
• Accessibility — sets the appropriate resize cursor while hovered/dragged; returns the full Response for the organism to interpret (drag_delta, double_clicked).

API

Axis — re-exported from Divider: Horizontal, Vertical.

Usage

#![allow(unused)]
fn main() {
use ouroboros_ui::atoms::{SplitterHandle, Axis};

// inside a left/right split: visible rule is vertical
let resp = SplitterHandle::new(Axis::Vertical).show(ui);
if resp.dragged() {
    let dx = resp.drag_delta().x;
    // adjust the left pane width by dx
}
}

Composition

Atom: paints the hairline/highlight directly and sets the cursor. Composes no other atoms; it is itself composed by the Splitter organism.

Notes

• Pass the orientation of the visible line, not the split direction — Axis::Vertical for a horizontal (left/right) split. This is the documented gotcha.
• show consumes the whole ui.max_rect() as the hit-target; give it a dedicated child Ui sized to the desired grab width.

See tokens · theming.