chore: init

Author: zombieJ

docs/demo/focus.md

@@ -0,0 +1,9 @@
+---
+title: Focus Utils
+---
+
+# Focus Utils Demo
+
+Demonstrates the usage of focus-related utility functions, including `limitTabRange`, `getFocusNodeList`, and `triggerFocus`.
+
+<code src="../examples/focus.tsx"></code>

docs/examples/focus.tsx

@@ -0,0 +1,34 @@
+import React, { useRef } from 'react';
+import {} from '../../src';
+
+export default function FocusDemo() {
+  const containerRef = useRef<HTMLDivElement>(null);
+
+  return (
+    <div style={{ padding: 32 }}>
+      <h2>Focus Utils Demo</h2>
+
+      {/* External buttons */}
+      <button>External Button 1</button>
+
+      {/* Middle container - Tab key cycling is limited within this area */}
+      <div
+        ref={containerRef}
+        style={{
+          border: '2px solid #1890ff',
+          padding: 24,
+          margin: 16,
+          borderRadius: 8,
+          backgroundColor: '#f0f8ff',
+        }}
+      >
+        <button>Container Button 1</button>
+        <button>Container Button 2</button>
+        <button>Container Button 3</button>
+      </div>
+
+      {/* External buttons */}
+      <button>External Button 2</button>
+    </div>
+  );
+}

src/Dom/focus.ts

@@ -56,48 +56,6 @@ export function getFocusNodeList(node: HTMLElement, includePositive = false) {
   return res;
 }
 
-let lastFocusElement = null;
-
-/** @deprecated Do not use since this may failed when used in async */
-export function saveLastFocusNode() {
-  lastFocusElement = document.activeElement;
-}
-
-/** @deprecated Do not use since this may failed when used in async */
-export function clearLastFocusNode() {
-  lastFocusElement = null;
-}
-
-/** @deprecated Do not use since this may failed when used in async */
-export function backLastFocusNode() {
-  if (lastFocusElement) {
-    try {
-      // 元素可能已经被移动了
-      lastFocusElement.focus();
-
-      /* eslint-disable no-empty */
-    } catch (e) {
-      // empty
-    }
-    /* eslint-enable no-empty */
-  }
-}
-
-export function limitTabRange(node: HTMLElement, e: KeyboardEvent) {
-  if (e.keyCode === 9) {
-    const tabNodeList = getFocusNodeList(node);
-    const lastTabNode = tabNodeList[e.shiftKey ? 0 : tabNodeList.length - 1];
-    const leavingTab =
-      lastTabNode === document.activeElement || node === document.activeElement;
-
-    if (leavingTab) {
-      const target = tabNodeList[e.shiftKey ? tabNodeList.length - 1 : 0];
-      target.focus();
-      e.preventDefault();
-    }
-  }
-}
-
 export interface InputFocusOptions extends FocusOptions {
   cursor?: 'start' | 'end' | 'all';
 }
@@ -137,3 +95,34 @@ export function triggerFocus(
     }
   }
 }
+
+// ======================================================
+// ==                    Lock Focus                    ==
+// ======================================================
+let focusElements: HTMLElement[] = [];
+
+function onWindowFocus(e: FocusEvent) {
+  const lastElement = focusElements[focusElements.length - 1];
+
+  console.log('lock focus', e.target, lastElement);
+}
+
+/**
+ * Lock focus in the element.
+ * It will force back to the first focusable element when focus leaves the element.
+ */
+export function lockFocus(element: HTMLElement): VoidFunction {
+  // Refresh focus elements
+  focusElements = focusElements.filter(ele => ele !== element);
+  focusElements.push(element);
+
+  // Just add event since it will de-duplicate
+  window.addEventListener('focusin', onWindowFocus, true);
+
+  return () => {
+    focusElements = focusElements.filter(ele => ele !== element);
+    if (focusElements.length === 0) {
+      window.removeEventListener('focusin', onWindowFocus, true);
+    }
+  };
+}