fix：按钮

pages/listingManagement/index.vue

 <template>
   <view class="container">
     <uni-nav-bar
+      v-if="!selectedCount"
       :fixed="true"
       background-color="rgba(214, 240, 255, 0.0)"
       status-bar
       rightWidth="300"
     >
       <block slot="left">
-        <view class="uni-nav-bar-text" @click="back">
+        <view @click="back">
           <text class="iconfont icon-fanhui"></text>
         </view>
       </block>
       <block slot="right" class="nav-right">
         <view class="header-buttons">
-          <button class="button">操作说明</button>
+          <text class="iconfont icon-shuoming"></text>
+        </view>
+      </block>
+    </uni-nav-bar>
+    <uni-nav-bar
+      v-else
+      :fixed="true"
+      background-color="#FFF"
+      status-bar
+      leftWidth="300"
+      rightWidth="300"
+    >
+      <block slot="left">
+        <view class="header-left" @click="headerClose">
+          <text class="close">X</text
+          ><view class="selected-count"> 已选择{{ selectedCount }}张图片</view>
+        </view>
+      </block>
+      <block slot="right" class="nav-right">
+        <view class="header-right">
+          <text class="iconfont icon-quanxuan"></text>
+          <text class="iconfont icon-shanchu"></text>
         </view>
       </block>
     </uni-nav-bar>
 
     <!-- 第二个模块：选中条数显示 -->
-    <view class="selected-count"> 已选择{{ selectedCount }}张图片</view>
-
     <!-- 第三个模块：照片显示模块 -->
     <view class="photo-box">
       <view class="photo-list">
@@ -332,33 +352,53 @@ export default {
   align-items: center;
   justify-content: center;
   text-align: center;
-
   .iconfont {
     font-size: 16px;
     line-height: 28.8px;
   }
 }
 
+.header-left {
+  display: flex;
+  justify-content: flex-start;
+  .close {
+    font-size: 20px;
+  }
+  .selected-count {
+    font-size: 14.4px;
+    line-height: 27px;
+    color: #000000;
+    font-weight: 500;
+    margin-left: 6.4px;
+  }
+}
 .nav-right {
   width: 192px;
 }
-
+::v-deep .uni-navbar__header-btns-left{
+  width: 300px!important;
+}
 .header-buttons {
   display: flex;
   align-items: center;
   margin-left: auto;
-
-  .button {
-    width: 89.6px;
+  width: 28.8px;
   height: 28.8px;
-    background: #ffffff;
-    border-radius: 14.4px;
-    margin-left: 12.8px;
-    font-family: PingFangSC-Regular;
-    font-size: 12.8px;
-    color: #000000;
-    line-height: 28.8px;
-    font-weight: 400;
+  border-radius: 50%;
+  background: #fff;
+  .iconfont {
+    margin: 0 auto;
+    &.icon-shuoming {
+    }
+  }
+}
+.header-right {
+  
+  .iconfont {
+    margin: 0 auto;
+    &.icon-quanxuan {
+      margin-right: 19.2px;
+    }
   }
 }
 
@@ -397,18 +437,6 @@ export default {
   }
 }
 
-.selected-count {
-  background-color: #fff;
-  padding: 6.4px;
-  font-size: 14.4px;
-  color: #000000;
-  line-height: 20.8px;
-  font-weight: 500;
-  border-radius: 6.4px;
-  margin-bottom: 12.8px;
-  padding-left: 25.6px;
-}
-
 .photo-box {
   width: 100%;
   height: 100%;