[new feature] ImagePreview: support component call (#3154)

packages/image-preview/demo/index.vue

@@ -11,6 +11,14 @@
     <demo-block :title="$t('button3')">
       <van-button @click="showImagePreview(0, 1000)">{{ $t('button3') }}</van-button>
     </demo-block>
+
+    <demo-block :title="$t('componentCall')">
+      <van-button @click="componentCall">{{ $t('componentCall') }}</van-button>
+      <van-image-preview
+        v-model="show"
+        :images="images"
+      />
+    </demo-block>
   </demo-section>
 </template>
 
@@ -29,16 +37,29 @@ export default {
     'zh-CN': {
       button1: '预览图片',
       button2: '指定初始位置',
-      button3: '异步关闭'
+      button3: '异步关闭',
+      componentCall: '组件调用'
     },
     'en-US': {
       button1: 'Show Images',
       button2: 'Custom Start Position',
-      button3: 'Async Close'
+      button3: 'Async Close',
+      componentCall: 'Component Call'
     }
   },
 
+  data() {
+    return {
+      show: false,
+      images
+    };
+  },
+
   methods: {
+    componentCall() {
+      this.show = true;
+    },
+
     showImagePreview(position, timer) {
       const instance = ImagePreview({
         images,