PanelSplitter

Guidelines#

Use it for list/detail layouts: Unibox list and thread, pipeline board and people board, conversation and details.

What you provide: label ("Resize conversation list"), valueText for screen readers ("260 pixels for the list"), min/max/now in pixels, isResizing, pointer handlers (onPointerDown/Move/Up), onKeyDown (arrow keys step the width) and onReset (double-click restores the default).

Anatomy: a 12px hit strip with a 1px border line that turns primary at 50% on hover and full primary on focus or drag, and a 12 × 48px grip pill in the middle.

Facts#

API#

TypeScript declarations emitted from src/components/ui/panel-splitter.tsx (the module also exports its other parts).

interface PanelSplitterProps {
    label: string;
    /** Human-readable state for screen readers, e.g. "320 pixels for the list". */
    valueText: string;
    min: number;
    max: number;
    now: number;
    isResizing: boolean;
    onPointerDown: (event: PointerEvent<HTMLElement>) => void;
    onPointerMove: (event: PointerEvent<HTMLElement>) => void;
    onPointerUp: (event: PointerEvent<HTMLElement>) => void;
    onKeyDown: (event: KeyboardEvent<HTMLElement>) => void;
    onReset: () => void;
    className?: string;
}
export declare function PanelSplitter({ label, valueText, min, max, now, isResizing, onPointerDown, onPointerMove, onPointerUp, onKeyDown, onReset, className, }: PanelSplitterProps): JSX.Element;

Example#

The code of the preview above: plain React.createElement against window.DigitalCrew, with realistic data.

<div id="root" class="p-6"></div>
<script>
(function () {
  var h = React.createElement, DC = window.DigitalCrew, I = DC.Icons;
function App() {
  var w = React.useState(260), drag = React.useState(false), start = React.useRef(null);
  function set(v) { w[1](Math.max(200, Math.min(420, v))); }
  return h("div", { className: "flex h-52 overflow-hidden rounded-lg border" },
    h("div", { style: { width: w[0] }, className: "shrink-0 p-4" },
      h("p", { className: "text-sm font-medium" }, "Conversations"),
      h("p", { className: "text-sm text-muted-foreground" }, "Drag the seam, use the arrow keys, or double-click to reset.")),
    h(DC.PanelSplitter, {
      label: "Resize conversation list", valueText: w[0] + " pixels for the list", min: 200, max: 420, now: w[0], isResizing: drag[0],
      onPointerDown: function (e) { start.current = { x: e.clientX, w: w[0] }; drag[1](true); e.currentTarget.setPointerCapture(e.pointerId); },
      onPointerMove: function (e) { if (start.current) set(start.current.w + e.clientX - start.current.x); },
      onPointerUp: function () { start.current = null; drag[1](false); },
      onKeyDown: function (e) { if (e.key === "ArrowLeft") set(w[0] - 16); if (e.key === "ArrowRight") set(w[0] + 16); },
      onReset: function () { w[1](260); } }),
    h("div", { className: "flex-1 p-4 bg-muted/40" }, h("p", { className: "text-sm font-medium" }, "Thread"), h("p", { className: "text-sm text-muted-foreground" }, "Claire Dubois · Re: annual plan")));
}
  ReactDOM.createRoot(document.getElementById("root")).render(h(DC.TooltipProvider, { delayDuration: 80 }, h(App)));
})();
</script>

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