fix(ImagePreview): double-scale and close-on-click-overlay may not work in certain scenarios (#12521)

packages/vant/src/image-preview/ImagePreviewItem.tsx

@@ -251,6 +251,14 @@ export default defineComponent({
       }
     };
 
+    const checkClose = (event: TouchEvent) => {
+      const isClickOverlay = event.target === swipeItem.value?.$el;
+
+      if (!props.closeOnClickOverlay && isClickOverlay) return;
+
+      emit('close');
+    };
+
     const checkTap = (event: TouchEvent) => {
       if (fingerNum > 1) {
         return;
@@ -272,19 +280,13 @@ export default defineComponent({
               doubleTapTimer = null;
               toggleScale();
             } else {
-              if (
-                !props.closeOnClickOverlay &&
-                event.target === swipeItem.value?.$el
-              ) {
-                return;
-              }
               doubleTapTimer = setTimeout(() => {
-                emit('close');
+                checkClose(event);
                 doubleTapTimer = null;
               }, TAP_TIME);
             }
           } else {
-            emit('close');
+            checkClose(event);
           }
         }
         // long press

packages/vant/src/image-preview/test/index.spec.ts

@@ -7,7 +7,7 @@ import {
 } from '../../../test';
 import { LONG_PRESS_START_TIME } from '../../utils';
 import ImagePreview from '../ImagePreview';
-import { images, triggerZoom } from './shared';
+import { images, triggerDoubleTap, triggerZoom } from './shared';
 import type { ImagePreviewInstance } from '../types';
 
 test('should swipe to current index after calling the swipeTo method', async () => {
@@ -230,38 +230,56 @@ test('should trigger scale after double clicking', async () => {
 
   await later();
   const swipe = wrapper.find('.van-swipe-item');
-  triggerDrag(swipe, 0, 0);
-  triggerDrag(swipe, 0, 0);
+
+  triggerDoubleTap(swipe);
   expect(onScale).toHaveBeenCalledWith({
     index: 0,
     scale: 2,
   });
 
-  await later();
-  triggerDrag(swipe, 0, 0);
-  triggerDrag(swipe, 0, 0);
+  triggerDoubleTap(swipe);
   expect(onScale).toHaveBeenLastCalledWith({
     index: 0,
     scale: 1,
   });
+
+  // when closeOnClickOverlay is set to false, it will not affect the zooming.
+  onScale.mockClear();
+  await wrapper.setProps({ closeOnClickOverlay: false });
+  triggerDoubleTap(swipe);
+  expect(onScale).toHaveBeenCalled();
 });
 
 test('should allow to disable double click gesture', async () => {
   const onScale = vi.fn();
+  const onClose = vi.fn();
   const wrapper = mount(ImagePreview, {
     props: {
       images,
       show: true,
       doubleScale: false,
+      onClose,
       onScale,
+      'onUpdate:show': (show) => {
+        wrapper.setProps({ show });
+      },
     },
   });
 
+  // The ImagePreview will close because double-click is disabled.
   await later();
   const swipe = wrapper.find('.van-swipe-item');
-  triggerDrag(swipe, 0, 0);
-  triggerDrag(swipe, 0, 0);
-  expect(onScale).toHaveBeenCalledTimes(0);
+  await triggerDoubleTap(swipe);
+  expect(onClose).toHaveBeenCalled();
+  expect(onScale).not.toHaveBeenCalled();
+
+  // The ImagePreview will not close when closeOnClickOverlay is set to false.
+  onClose.mockClear();
+  await wrapper.setProps({ closeOnClickOverlay: false, show: true });
+  await triggerDrag(swipe, 0, 0);
+  expect(onClose).not.toHaveBeenCalled();
+  await triggerDoubleTap(swipe, 0, 0);
+  expect(onClose).not.toHaveBeenCalled();
 });
 
 test('zoom in and drag image to move', async () => {

packages/vant/src/image-preview/test/shared.ts

@@ -1,6 +1,7 @@
+import { nextTick } from 'vue';
 import { DOMWrapper } from '@vue/test-utils/dist/domWrapper';
 import { cdnURL } from '../../../docs/site';
-import { trigger } from '../../../test';
+import { trigger, triggerDrag } from '../../../test';
 
 export const images = [
   cdnURL('apple-1.jpeg'),
@@ -38,3 +39,14 @@ export function triggerZoom(
 
   trigger(el, 'touchend', 0, 0, { touchList: [] });
 }
+
+export function triggerDoubleTap(
+  el: HTMLElement | DOMWrapper<Element>,
+  x: number = 0,
+  y: number = 0,
+) {
+  triggerDrag(el, x, y);
+  triggerDrag(el, x, y);
+
+  return nextTick();
+}