Open view container on drop if it is the only visible one (microsoft#196585)

microsoft#196359 Open view container on drop if it is the only visible one

Author: sandy081

src/vs/workbench/browser/parts/activitybar/activitybarPart.ts

@@ -208,15 +208,15 @@ export class ActivityBarCompositeBar extends PaneCompositeBar {
 		@IWorkbenchEnvironmentService environmentService: IWorkbenchEnvironmentService,
 		@IConfigurationService private readonly configurationService: IConfigurationService,
 		@IMenuService private readonly menuService: IMenuService,
-		@IWorkbenchLayoutService private readonly layoutService: IWorkbenchLayoutService,
+		@IWorkbenchLayoutService layoutService: IWorkbenchLayoutService,
 	) {
 		super({
 			...options,
 			fillExtraContextMenuActions: (actions, e) => {
 				options.fillExtraContextMenuActions(actions, e);
 				this.fillContextMenuActions(actions, e);
 			}
-		}, part, paneCompositePart, instantiationService, storageService, extensionService, viewDescriptorService, contextKeyService, environmentService);
+		}, part, paneCompositePart, instantiationService, storageService, extensionService, viewDescriptorService, contextKeyService, environmentService, layoutService);
 
 		if (showGlobalActivities) {
 			this.globalCompositeBar = this._register(instantiationService.createInstance(GlobalCompositeBar, () => this.getContextMenuActions(), (theme: IColorTheme) => this.options.colors(theme), this.options.activityHoverOptions));

src/vs/workbench/browser/parts/paneCompositeBar.ts

@@ -106,6 +106,7 @@ export class PaneCompositeBar extends Disposable {
 		@IViewDescriptorService private readonly viewDescriptorService: IViewDescriptorService,
 		@IContextKeyService protected readonly contextKeyService: IContextKeyService,
 		@IWorkbenchEnvironmentService private readonly environmentService: IWorkbenchEnvironmentService,
+		@IWorkbenchLayoutService protected readonly layoutService: IWorkbenchLayoutService,
 	) {
 		super();
 		this.location = paneCompositePart.partId === Parts.PANEL_PART
@@ -208,6 +209,12 @@ export class PaneCompositeBar extends Disposable {
 
 		if (to === this.location) {
 			this.onDidRegisterViewContainers([container]);
+
+			// Open view container if part is visible and there is no other view container opened
+			const visibleComposites = this.compositeBar.getVisibleComposites();
+			if (!this.paneCompositePart.getActivePaneComposite() && this.layoutService.isVisible(this.paneCompositePart.partId) && visibleComposites.length) {
+				this.paneCompositePart.openPaneComposite(visibleComposites[0].id);
+			}
 		}
 	}