直播回显问题修复

src/views/yqrange/create-live.vue

@@ -1432,7 +1432,7 @@
             return item.backgroundImageId == vm.formData.backgroundImageId;
           });
 
-          if(selectedImages != null){
+          if(selectedImages != null && selectedImages.length > 0){
             this.backgroundImageUrl = selectedImages[0].imageUrl;
           }
         }