[new feature] Tabs: support switch tabs with swipe gestrue in the content (#694)

docs/demos/views/tab.vue

@@ -58,6 +58,14 @@
         </van-tab>
       </van-tabs>
     </demo-block>
+
+    <demo-block :title="$t('title8')">
+      <van-tabs :active="active" swipeable>
+        <van-tab :title="$t('tab') + index" v-for="index in tabs" :key="index">
+          {{ $t('content') }} {{ index }}
+        </van-tab>
+      </van-tabs>
+    </demo-block>
   </demo-section>
 </template>
 
@@ -71,7 +79,8 @@ export default {
       title4: '样式风格',
       title5: '点击事件',
       title6: '粘性布局',
-      title7: '自定义标签'
+      title7: '自定义标签',
+      title8: '滑动切换'
     },
     'en-US': {
       tab: 'Tab ',
@@ -81,7 +90,8 @@ export default {
       title4: 'Card Style',
       title5: 'Click Event',
       title6: 'Sticky',
-      title7: 'Custom Tab'
+      title7: 'Custom Tab',
+      title8: 'Swipeable'
     }
   },
 

docs/markdown/en-US/tab.md

@@ -124,6 +124,18 @@ Use title slot to custom tab title
 </van-tabs>
 ```
 
+#### Swipeable
+
+In swipeable mode, you can switch tabs with swipe gestrue in the content
+
+```html
+<van-tabs :active="active" swipeable>
+  <van-tab v-for="index in 4" :title="'tab ' + index">
+    content {{ index }}
+  </van-tab>
+</van-tabs>
+```
+
 ### Tabs API
 
 | Attribute | Description | Type | Default | Accepted Values |
@@ -132,6 +144,8 @@ Use title slot to custom tab title
 | active | Index of active tab | `String` `Number` | `0` | - |
 | duration | Toggle tab's animation time | `Number` | `0.2` | - | - |
 | swipe-threshold | Set swipe tabs threshold | `Number` | `4` | - | - |
+| sticky | Whether to use sticky mode | `Boolean` | `false` | - |
+| swipeable | Whether to switch tabs with swipe gestrue in the content | `Boolean` | `false` | - |
 
 ### Tab API
 

docs/markdown/zh-CN/tab.md

@@ -124,6 +124,18 @@ export default {
 </van-tabs>
 ```
 
+#### 滑动切换
+
+通过`swipeable`属性可以开启滑动切换tab
+
+```html
+<van-tabs :active="active" swipeable>
+  <van-tab v-for="index in 4" :title="'选项 ' + index">
+    内容 {{ index }}
+  </van-tab>
+</van-tabs>
+```
+
 ### Tabs API
 
 | 参数 | 说明 | 类型 | 默认值 | 可选 |
@@ -133,6 +145,7 @@ export default {
 | duration | 切换 tab 的动画时间 | `Number` | `0.2` | - |
 | swipe-threshold | 滚动阀值，设置 Tab 超过多少个可滚动 | `Number` | `4` | - |
 | sticky | 是否使用粘性定位布局 | `Boolean` | `false` | - |
+| swipeable | 是否可以滑动内容切换 | `Boolean` | `false` | - |
 
 ### Tab API