webview: add support for activeWebviewPanelId

packages/plugin-ext/src/main/browser/plugin-ext-frontend-module.ts

@@ -82,6 +82,7 @@ import { PluginMenuCommandAdapter } from './menus/plugin-menu-command-adapter';
 import './theme-icon-override';
 import { PluginTerminalRegistry } from './plugin-terminal-registry';
 import { DnDFileContentStore } from './view/dnd-file-content-store';
+import { WebviewContextKeys } from './webview/webview-context-keys';
 
 export default new ContainerModule((bind, unbind, isBound, rebind) => {
 
@@ -177,6 +178,8 @@ export default new ContainerModule((bind, unbind, isBound, rebind) => {
     bind(WebviewWidget).toSelf();
     bind(WebviewWidgetFactory).toDynamicValue(ctx => new WebviewWidgetFactory(ctx.container)).inSingletonScope();
     bind(WidgetFactory).toService(WebviewWidgetFactory);
+    bind(WebviewContextKeys).toSelf().inSingletonScope();
+    bind(FrontendApplicationContribution).toService(WebviewContextKeys);
 
     bind(CustomEditorContribution).toSelf().inSingletonScope();
     bind(CommandContribution).toService(CustomEditorContribution);

packages/plugin-ext/src/main/browser/webview/webview-context-keys.ts

@@ -0,0 +1,49 @@
+// *****************************************************************************
+// Copyright (C) 2023 Ericsson and others.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License v. 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0.
+//
+// This Source Code may also be made available under the following Secondary
+// Licenses when the conditions for such availability set forth in the Eclipse
+// Public License v. 2.0 are satisfied: GNU General Public License, version 2
+// with the GNU Classpath Exception which is available at
+// https://www.gnu.org/software/classpath/license.html.
+//
+// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { inject, injectable, postConstruct } from '@theia/core/shared/inversify';
+import { ContextKey, ContextKeyService } from '@theia/core/lib/browser/context-key-service';
+import { ApplicationShell, FocusTracker, Widget } from '@theia/core/lib/browser';
+import { WebviewWidget } from './webview';
+
+@injectable()
+export class WebviewContextKeys {
+
+    /**
+     * Context key representing the `viewType` of the active `WebviewWidget`, if any.
+     */
+    activeWebviewPanelId: ContextKey<string>;
+
+    @inject(ApplicationShell)
+    protected applicationShell: ApplicationShell;
+
+    @inject(ContextKeyService)
+    protected contextKeyService: ContextKeyService;
+
+    @postConstruct()
+    protected postConstruct(): void {
+        this.activeWebviewPanelId = this.contextKeyService.createKey('activeWebviewPanelId', '');
+        this.applicationShell.onDidChangeCurrentWidget(this.handleDidChangeCurrentWidget, this);
+    }
+
+    protected handleDidChangeCurrentWidget(change: FocusTracker.IChangedArgs<Widget>): void {
+        if (change.newValue instanceof WebviewWidget) {
+            this.activeWebviewPanelId.set(change.newValue.viewType);
+        } else {
+            this.activeWebviewPanelId.set('');
+        }
+    }
+}