fixes #26

resources/vue/components/courseware/CoursewareManagerElement.vue

@@ -150,6 +150,7 @@ export default {
             discardStateArrayChildren: [],
             sortArrayContainers: [],
             discardStateArrayContainers: [],
+            insertingInProgress: false,
         };
     },
     computed: {
@@ -300,6 +301,8 @@ export default {
             this.$emit('selectElement', target);
         },
         async insertElement(data) {
+            if(!this.insertingInProgress) {
+                this.insertingInProgress = true;
                 let source = data.source;
                 let element = data.element;
                 if (source === 'self') {
@@ -328,9 +331,12 @@ export default {
                     console.log(source);
                     console.log(element);
                 }
-
+                this.insertingInProgress = false;
+            }
         },
         async insertContainer(data) {
+            if(!this.insertingInProgress) {
+                this.insertingInProgress = true;
                 let source = data.source;
                 let container = data.container;
                 if (source === 'self') {
@@ -357,9 +363,13 @@ export default {
                     console.log(source);
                     console.log(container);
                 }
+                this.insertingInProgress = false;
+            }
 
         },
         async insertBlock(data) {
+            if(!this.insertingInProgress) {
+                this.insertingInProgress = true;
                 let source = data.source;
                 let block = data.block;
                 if (source === 'self') {
@@ -410,6 +420,8 @@ export default {
                 } else {
                     console.debug('unreliable source:', source, block);
                 }
+                this.insertingInProgress = false;
+            }
         },
 
         sortChildren() {