Added upload pending prompt on close/reload

changelog/unreleased/enhancement-prompt-on-window-close-pending-upload

@@ -0,0 +1,8 @@
+Enhancement: Prompts leaving user about pending uploads
+
+Added an unload event listener that detects closes/ reloads/ navigates to another URL. 
+Added prompt that ask for confirmation to leave site on unload events if uploads pending.
+Removed the event listener before destroy of component. 
+
+https://github.com/owncloud/web/issues/2590
+https://github.com/owncloud/web/pull/4840

packages/web-app-files/src/components/UploadProgress.vue

@@ -108,6 +108,10 @@ export default {
       } else {
         return 100
       }
+    },
+
+    uploadPending() {
+      return this.totalUploadProgress < 100
     }
   },
   watch: {
@@ -124,10 +128,20 @@ export default {
         this.delayForScreenreader(() => this.$refs.progressbar.$el.focus())
       })
     })
+    window.addEventListener('beforeunload', this.handlerClose)
+  },
+  beforeDestroy() {
+    window.removeEventListener('beforeunload', this.handlerClose)
   },
   methods: {
     $_toggleExpanded() {
       this.expanded = !this.expanded
+    },
+    handlerClose(event) {
+      if (this.uploadPending) {
+        event.preventDefault()
+        event.returnValue = ''
+      }
     }
   }
 }