feature: improve ApplicationGroup

app/assets/javascripts/ui_models/application_group.ts

@@ -11,11 +11,12 @@ import {
   ThemeManager
 } from '@/services';
 import { AppState } from '@/ui_models/app_state';
+import { pull } from 'lodash';
 
 type AppManagerChangeCallback = () => void
 
 export class ApplicationGroup {
-  
+
   $compile: ng.ICompileService
   $rootScope: ng.IRootScopeService
   $timeout: ng.ITimeoutService
@@ -50,8 +51,9 @@ export class ApplicationGroup {
     }
     if (this.applications.length === 0) {
       this.createDefaultApplication();
+    } else {
+      this.notifyObserversOfAppChange();
     }
-    this.notifyObserversOfAppChange();
   }
 
   private createNewApplication() {
@@ -121,6 +123,10 @@ export class ApplicationGroup {
     if (this.application) {
       callback();
     }
+
+    return () => {
+      pull( this.changeObservers, callback)
+    }
   }
 
   private notifyObserversOfAppChange() {