[fix] 修复拖拽上传图片组件，删除第一个图片会与添加按钮重叠的bug

tuniao-ui/components/tn-image-upload-drag/tn-image-upload-drag.vue

@@ -7,6 +7,7 @@
       }"
       @mouseenter="mouseEnterArea"
       @mouseleave="mouseLeaveArea"
+      v-if="show"
     >
       <block
         v-for="(item, index) in lists"
@@ -298,7 +299,8 @@
           y: 0
         },
         timer: null,
-        dragging: false
+        dragging: false,
+        show:true
       }
     },
     watch: {
@@ -551,6 +553,8 @@
         if (index >= 0 && index < this.lists.length) {
           let currentItemIndex = this.lists[index].index
           this.lists.splice(index, 1)
+          this.show = false;
+          setTimeout(()=>{
             // 重新排列列表信息
             for (let item of this.lists) {
               if (item.index > currentItemIndex) {
@@ -565,8 +569,8 @@
                 })
               }
             }
-          
             this.updateAddBtnPositioin()
+          },50)
         }
       },
       // 预览图片
@@ -684,8 +688,10 @@
       updateAddBtnPositioin() {
         if (this.lists.length >= this.maxCount) return
         
+        setTimeout(()=>{
           this.addBtn.x = (this.lists.length % this.baseData.columns) * this.baseData.widthPx
           this.addBtn.y = Math.floor(this.lists.length / this.baseData.columns) * this.baseData.heightPx
+        },50);
       },
       // 获取排序后数据
       sortList() {