feat: hide activity part if no activities are registered

closes #107

projects/scion/workbench-application-platform/src/lib/core/application-registry.service.ts

@@ -9,7 +9,7 @@
  */
 
 import { Injectable } from '@angular/core';
-import { ApplicationManifest, HOST_APPLICATION_SYMBOLIC_NAME, ApplicationConfig } from './metadata';
+import { ApplicationConfig, ApplicationManifest, HOST_APPLICATION_SYMBOLIC_NAME } from './metadata';
 import { Defined } from './defined.util';
 import { ManifestRegistry } from './manifest-registry.service';
 import { Application } from '@scion/workbench-application-platform.api';

projects/scion/workbench/src/lib/activity-part/workbench-activity-part.service.ts

@@ -13,11 +13,12 @@ import { ActivatedRouteSnapshot, Router } from '@angular/router';
 import { ACTIVITY_DATA_KEY, ACTIVITY_OUTLET_NAME } from '../workbench.constants';
 import { InternalWorkbenchRouter } from '../routing/workbench-router.service';
 import { Activity, InternalActivity } from './activity';
+import { BehaviorSubject, Observable } from 'rxjs';
 
 @Injectable()
 export class WorkbenchActivityPartService {
 
-  private _activities: Activity[] = [];
+  private _activities$ = new BehaviorSubject<Activity[]>([]);
 
   constructor(private _router: Router,
               private _wbRouter: InternalWorkbenchRouter,
@@ -28,7 +29,14 @@ export class WorkbenchActivityPartService {
    * Returns the list of activities.
    */
   public get activities(): Activity[] {
-    return this._activities;
+    return this._activities$.value;
+  }
+
+  /**
+   * Returns the list of activities as {Observable}, which emits when activities are added or removed.
+   */
+  public get activities$(): Observable<Activity[]> {
+    return this._activities$;
   }
 
   /**
@@ -42,7 +50,7 @@ export class WorkbenchActivityPartService {
    * Returns the activity which is currently active, or `null` otherwise.
    */
   public get activeActivity(): Activity | null {
-    return this._activities.find(it => it.active) || null;
+    return this.activities.find(it => it.active) || null;
   }
 
   /**
@@ -55,8 +63,9 @@ export class WorkbenchActivityPartService {
       return this._router.navigate([{outlets: {[ACTIVITY_OUTLET_NAME]: activity.active ? null : activity.commands}}], {
         queryParamsHandling: 'preserve'
       });
-    } else if (activity.target === 'view') {
-      return this._wbRouter.navigate(activity.commands);
+    }
+    else if (activity.target === 'view') {
+      return this._wbRouter.navigate(activity.commands, {activateIfPresent: false});
     }
     throw Error('[IllegalActivityTargetError] Target must be \'activity-panel\' or \'view\'');
   }
@@ -65,19 +74,16 @@ export class WorkbenchActivityPartService {
    * Adds an activity to the activity bar.
    */
   public addActivity(activity: Activity): void {
-    this._activities.push(activity);
-    this._activities.sort((a1, a2) => (a1.position || 0) - (a2.position || 0));
+    const activities = [...this.activities, activity].sort((a1, a2) => (a1.position || 0) - (a2.position || 0));
+    this._activities$.next(activities);
   }
 
   /**
    * Removes an activity from the activity bar.
    */
   public removeActivity(activity: Activity): void {
-    const index = this._activities.findIndex(it => it === activity);
-    if (index === -1) {
-      throw Error('[IllegalStateError] Activity not registered');
-    }
-    this._activities.splice(index, 1);
+    const activities = this.activities.filter(it => it !== activity);
+    this._activities$.next(activities);
   }
 
   /**

projects/scion/workbench/src/lib/routing/activity.resolver.ts

@@ -57,7 +57,7 @@ export class ActivityResolver implements Resolve<Activity>, OnDestroy {
       .pipe(
         filter(event => event instanceof NavigationEnd),
         filter(() => !this._router.routerState.snapshot.root.children.some(it => it.outlet === ACTIVITY_OUTLET_NAME)),
-        takeUntil(this._destroy$)
+        takeUntil(this._destroy$),
       )
       .subscribe(() => {
         this.deactivateActivity();

projects/scion/workbench/src/lib/workbench.component.html

@@ -1,5 +1,5 @@
 <ng-container #content_host></ng-container> <!-- placed upfront to not cover other elements, e.g. sashes or popus -->
-<wb-activity-part></wb-activity-part>
+<wb-activity-part *ngIf="activitiesVisible$ | async"></wb-activity-part>
 <wb-view-part-grid></wb-view-part-grid>
 <ng-container #overlay_host></ng-container>
 <wb-message-box-stack></wb-message-box-stack>

projects/scion/workbench/src/lib/workbench.component.scss

@@ -24,11 +24,14 @@
     flex: none;
   }
 
+  > wb-activity-part + wb-view-part-grid {
+    position: relative; // forms a stacking context to show 'box-shadow'
+    box-shadow: -1px 0 2px 0 rgba(0, 0, 0, .4);
+  }
+
   > wb-view-part-grid {
     @include preventPointerEvents;
     flex: auto;
-    position: relative; // forms a stacking context to show 'box-shadow'
-    box-shadow: -1px 0 2px 0 rgba(0, 0, 0, .4);
   }
 
   > wb-message-box-stack {

projects/scion/workbench/src/lib/workbench.component.ts

@@ -12,6 +12,9 @@ import { Component, HostBinding, ViewChild, ViewContainerRef } from '@angular/co
 import { WorkbenchLayoutService } from './workbench-layout.service';
 import { OverlayHostRef } from './overlay-host-ref.service';
 import { ContentHostRef } from './content-projection/content-host-ref.service';
+import { filter, map } from 'rxjs/operators';
+import { Observable } from 'rxjs';
+import { WorkbenchActivityPartService } from './activity-part/workbench-activity-part.service';
 
 @Component({
   selector: 'wb-workbench',
@@ -20,6 +23,8 @@ import { ContentHostRef } from './content-projection/content-host-ref.service';
 })
 export class WorkbenchComponent {
 
+  public activitiesVisible$: Observable<boolean>;
+
   @ViewChild('overlay_host', {read: ViewContainerRef})
   public set overlayHost(overlayHost: ViewContainerRef) {
     this._overlayHostRef.set(overlayHost);
@@ -36,7 +41,13 @@ export class WorkbenchComponent {
   }
 
   constructor(private _workbenchLayout: WorkbenchLayoutService,
+              private _activityPartService: WorkbenchActivityPartService,
               private _overlayHostRef: OverlayHostRef,
               private _contentHostRef: ContentHostRef) {
+    this.activitiesVisible$ = this._activityPartService.activities$
+      .pipe(
+        map(activities => activities.filter(activity => activity.visible)),
+        map(activities => activities.length > 0),
+      );
   }
 }