chore(Popover): change name of default slot to reference

src/popover/README.zh-CN.md

@@ -57,6 +57,6 @@ Vue.use(Popover);
 
 ### Slots
 
-| 名称    | 说明                 |
-| ------- | -------------------- |
-| default | 自定义菜单的展示内容 |
+| 名称      | 说明                        |
+| --------- | --------------------------- |
+| reference | 触发 Popover 显示的元素内容 |

src/popover/demo/index.vue

@@ -7,9 +7,11 @@
         placement="bottom"
         style="margin-left: 16px;"
       >
-        <van-button type="primary" @click="show.lightTheme = true">
-          {{ t('lightTheme') }}
-        </van-button>
+        <template #reference>
+          <van-button type="primary" @click="show.lightTheme = true">
+            {{ t('lightTheme') }}
+          </van-button>
+        </template>
       </van-popover>
       <van-popover
         v-model="show.darkTheme"
@@ -18,9 +20,11 @@
         placement="bottom"
         style="margin-left: 16px;"
       >
-        <van-button type="primary" @click="show.darkTheme = true">
-          {{ t('darkTheme') }}
-        </van-button>
+        <template #reference>
+          <van-button type="primary" @click="show.darkTheme = true">
+            {{ t('darkTheme') }}
+          </van-button>
+        </template>
       </van-popover>
     </demo-block>
 
@@ -55,7 +59,9 @@
           :actions="t('shortActions')"
           :placement="currentPlacement"
         >
-          <div class="demo-popover-refer" />
+          <template #reference>
+            <div class="demo-popover-refer" />
+          </template>
         </van-popover>
       </div>
     </demo-block>
@@ -67,9 +73,11 @@
         placement="top"
         style="margin-left: 16px;"
       >
-        <van-button type="primary" @click="show.showIcon = true">
-          {{ t('showIcon') }}
-        </van-button>
+        <template #reference>
+          <van-button type="primary" @click="show.showIcon = true">
+            {{ t('showIcon') }}
+          </van-button>
+        </template>
       </van-popover>
 
       <van-popover
@@ -78,9 +86,11 @@
         placement="top"
         style="margin-left: 16px;"
       >
-        <van-button type="primary" @click="show.disabled = true">
-          {{ t('disabled') }}
-        </van-button>
+        <template #reference>
+          <van-button type="primary" @click="show.disabled = true">
+            {{ t('disabled') }}
+          </van-button>
+        </template>
       </van-popover>
     </demo-block>
   </demo-section>

src/popover/index.js

@@ -168,7 +168,7 @@ export default createComponent({
           <div class={bem('arrow')} />
           {this.actions.map(this.renderAction)}
         </Popup>
-        {this.slots('default')}
+        {this.slots('reference')}
       </span>
     );
   },