Improve widget specific status bar handling

packages/core/src/browser/frontend-application-module.ts

@@ -144,6 +144,7 @@ import { bindTreePreferences } from './tree';
 import { OpenWithService } from './open-with-service';
 import { ViewColumnService } from './shell/view-column-service';
 import { DomInputUndoRedoHandler, UndoRedoHandler, UndoRedoHandlerService } from './undo-redo-handler';
+import { WidgetStatusBarContribution, WidgetStatusBarService } from './widget-status-bar-service';
 
 export { bindResourceProvider, bindMessageService, bindPreferenceService };
 
@@ -471,4 +472,8 @@ export const frontendApplicationModule = new ContainerModule((bind, _unbind, _is
     bindContributionProvider(bind, UndoRedoHandler);
     bind(DomInputUndoRedoHandler).toSelf().inSingletonScope();
     bind(UndoRedoHandler).toService(DomInputUndoRedoHandler);
+
+    bind(WidgetStatusBarService).toSelf().inSingletonScope();
+    bind(FrontendApplicationContribution).toService(WidgetStatusBarService);
+    bindContributionProvider(bind, WidgetStatusBarContribution);
 });

packages/core/src/browser/index.ts

@@ -48,3 +48,4 @@ export * from './styling-service';
 export * from './hover-service';
 export * from './saveable-service';
 export * from './undo-redo-handler';
+export * from './widget-status-bar-service';

packages/core/src/browser/widget-status-bar-service.ts

@@ -0,0 +1,84 @@
+// *****************************************************************************
+// Copyright (C) 2024 TypeFox 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-only WITH Classpath-exception-2.0
+// *****************************************************************************
+
+import { inject, injectable, named } from 'inversify';
+import { Widget } from './widgets';
+import { StatusBar } from './status-bar';
+import { FrontendApplicationContribution } from './frontend-application-contribution';
+import { ContributionProvider } from '../common';
+import { FrontendApplication } from './frontend-application';
+
+export const WidgetStatusBarContribution = Symbol('WidgetStatusBarContribution');
+
+export interface WidgetStatusBarContribution<T extends Widget> {
+    canHandle(widget: Widget): widget is T;
+    activate(statusBar: StatusBar, widget: T): void;
+    deactivate(statusBar: StatusBar): void;
+}
+
+/**
+ * Creates an empty {@link WidgetStatusBarContribution} that does nothing.
+ * Useful for widgets that are not handled by any other contribution, for example:
+ * * Settings widget
+ * * Welcome widget
+ * * Webview widget
+ *
+ * @param prototype Prototype to identify the kind of the widget.
+ * @returns An empty {@link WidgetStatusBarContribution}.
+ */
+export function noopWidgetStatusBarContribution(prototype: Function): WidgetStatusBarContribution<Widget> {
+    return {
+        canHandle(widget: Widget): widget is Widget {
+            return widget instanceof prototype;
+        },
+        activate: () => { },
+        deactivate: () => { }
+    };
+}
+
+@injectable()
+export class WidgetStatusBarService implements FrontendApplicationContribution {
+
+    @inject(ContributionProvider) @named(WidgetStatusBarContribution)
+    protected readonly contributionProvider: ContributionProvider<WidgetStatusBarContribution<Widget>>;
+
+    @inject(StatusBar)
+    protected readonly statusBar: StatusBar;
+
+    onStart(app: FrontendApplication): void {
+        app.shell.onDidChangeCurrentWidget(event => {
+            if (event.newValue) {
+                this.show(event.newValue);
+            }
+        });
+    }
+
+    protected show(widget: Widget): void {
+        const contributions = this.contributionProvider.getContributions();
+        // If any contribution can handle the widget, activate it
+        // If none can, keep everything as is
+        if (contributions.some(contribution => contribution.canHandle(widget))) {
+            for (const contribution of contributions) {
+                // Deactivate all contributions
+                contribution.deactivate(this.statusBar);
+                if (contribution.canHandle(widget)) {
+                    // Selectively re-activate them
+                    contribution.activate(this.statusBar, widget);
+                }
+            }
+        }
+    }
+}

packages/editor/src/browser/editor-contribution.ts

@@ -20,7 +20,9 @@ import { injectable, inject, optional } from '@theia/core/shared/inversify';
 import { StatusBarAlignment, StatusBar } from '@theia/core/lib/browser/status-bar/status-bar';
 import {
     FrontendApplicationContribution, DiffUris, DockLayout,
-    QuickInputService, KeybindingRegistry, KeybindingContribution, SHELL_TABBAR_CONTEXT_SPLIT, ApplicationShell
+    QuickInputService, KeybindingRegistry, KeybindingContribution, SHELL_TABBAR_CONTEXT_SPLIT, ApplicationShell,
+    WidgetStatusBarContribution,
+    Widget
 } from '@theia/core/lib/browser';
 import { ContextKeyService } from '@theia/core/lib/browser/context-key-service';
 import { CommandHandler, DisposableCollection, MenuContribution, MenuModelRegistry } from '@theia/core';
@@ -33,9 +35,9 @@ import { EditorWidget } from './editor-widget';
 import { EditorLanguageStatusService } from './language-status/editor-language-status-service';
 
 @injectable()
-export class EditorContribution implements FrontendApplicationContribution, CommandContribution, KeybindingContribution, MenuContribution {
+export class EditorContribution implements FrontendApplicationContribution,
+    CommandContribution, KeybindingContribution, MenuContribution, WidgetStatusBarContribution<EditorWidget> {
 
-    @inject(StatusBar) protected readonly statusBar: StatusBar;
     @inject(EditorManager) protected readonly editorManager: EditorManager;
     @inject(EditorLanguageStatusService) protected readonly languageStatusService: EditorLanguageStatusService;
     @inject(ApplicationShell) protected readonly shell: ApplicationShell;
@@ -48,9 +50,6 @@ export class EditorContribution implements FrontendApplicationContribution, Comm
 
     onStart(): void {
         this.initEditorContextKeys();
-
-        this.updateStatusBar();
-        this.editorManager.onCurrentEditorChanged(() => this.updateStatusBar());
     }
 
     protected initEditorContextKeys(): void {
@@ -72,33 +71,41 @@ export class EditorContribution implements FrontendApplicationContribution, Comm
     }
 
     protected readonly toDisposeOnCurrentEditorChanged = new DisposableCollection();
-    protected updateStatusBar(): void {
+
+    canHandle(widget: Widget): widget is EditorWidget {
+        return widget instanceof EditorWidget;
+    }
+
+    activate(statusBar: StatusBar, widget: EditorWidget): void {
         this.toDisposeOnCurrentEditorChanged.dispose();
+        const editor = widget.editor;
+        this.updateLanguageStatus(statusBar, editor);
+        this.updateEncodingStatus(statusBar, editor);
+        this.setCursorPositionStatus(statusBar, editor);
+        this.toDisposeOnCurrentEditorChanged.pushAll([
+            editor.onLanguageChanged(() => this.updateLanguageStatus(statusBar, editor)),
+            editor.onEncodingChanged(() => this.updateEncodingStatus(statusBar, editor)),
+            editor.onCursorPositionChanged(() => this.setCursorPositionStatus(statusBar, editor))
+        ]);
+    }
 
-        const widget = this.editorManager.currentEditor;
-        const editor = widget && widget.editor;
-        this.updateLanguageStatus(editor);
-        this.updateEncodingStatus(editor);
-        this.setCursorPositionStatus(editor);
-        if (editor) {
-            this.toDisposeOnCurrentEditorChanged.pushAll([
-                editor.onLanguageChanged(() => this.updateLanguageStatus(editor)),
-                editor.onEncodingChanged(() => this.updateEncodingStatus(editor)),
-                editor.onCursorPositionChanged(() => this.setCursorPositionStatus(editor))
-            ]);
-        }
+    deactivate(statusBar: StatusBar): void {
+        this.toDisposeOnCurrentEditorChanged.dispose();
+        this.updateLanguageStatus(statusBar, undefined);
+        this.updateEncodingStatus(statusBar, undefined);
+        this.setCursorPositionStatus(statusBar, undefined);
     }
 
-    protected updateLanguageStatus(editor: TextEditor | undefined): void {
+    protected updateLanguageStatus(statusBar: StatusBar, editor: TextEditor | undefined): void {
         this.languageStatusService.updateLanguageStatus(editor);
     }
 
-    protected updateEncodingStatus(editor: TextEditor | undefined): void {
+    protected updateEncodingStatus(statusBar: StatusBar, editor: TextEditor | undefined): void {
         if (!editor) {
-            this.statusBar.removeElement('editor-status-encoding');
+            statusBar.removeElement('editor-status-encoding');
             return;
         }
-        this.statusBar.setElement('editor-status-encoding', {
+        statusBar.setElement('editor-status-encoding', {
             text: SUPPORTED_ENCODINGS[editor.getEncoding()].labelShort,
             alignment: StatusBarAlignment.RIGHT,
             priority: 10,
@@ -107,13 +114,13 @@ export class EditorContribution implements FrontendApplicationContribution, Comm
         });
     }
 
-    protected setCursorPositionStatus(editor: TextEditor | undefined): void {
+    protected setCursorPositionStatus(statusBar: StatusBar, editor: TextEditor | undefined): void {
         if (!editor) {
-            this.statusBar.removeElement('editor-status-cursor-position');
+            statusBar.removeElement('editor-status-cursor-position');
             return;
         }
         const { cursor } = editor;
-        this.statusBar.setElement('editor-status-cursor-position', {
+        statusBar.setElement('editor-status-cursor-position', {
             text: nls.localizeByDefault('Ln {0}, Col {1}', cursor.line + 1, editor.getVisibleColumn(cursor)),
             alignment: StatusBarAlignment.RIGHT,
             priority: 100,

packages/editor/src/browser/editor-frontend-module.ts

@@ -19,7 +19,7 @@ import '../../src/browser/language-status/editor-language-status.css';
 
 import { ContainerModule } from '@theia/core/shared/inversify';
 import { CommandContribution, MenuContribution } from '@theia/core/lib/common';
-import { OpenHandler, WidgetFactory, FrontendApplicationContribution, KeybindingContribution } from '@theia/core/lib/browser';
+import { OpenHandler, WidgetFactory, FrontendApplicationContribution, KeybindingContribution, WidgetStatusBarContribution } from '@theia/core/lib/browser';
 import { VariableContribution } from '@theia/variable-resolver/lib/browser';
 import { EditorManager, EditorAccess, ActiveEditorAccess, CurrentEditorAccess } from './editor-manager';
 import { EditorContribution } from './editor-contribution';
@@ -59,7 +59,6 @@ export default new ContainerModule(bind => {
     bind(KeybindingContribution).toService(EditorKeybindingContribution);
 
     bind(EditorContribution).toSelf().inSingletonScope();
-    bind(FrontendApplicationContribution).toService(EditorContribution);
     bind(EditorLanguageStatusService).toSelf().inSingletonScope();
 
     bind(EditorLineNumberContribution).toSelf().inSingletonScope();
@@ -73,7 +72,13 @@ export default new ContainerModule(bind => {
 
     bind(VariableContribution).to(EditorVariableContribution).inSingletonScope();
 
-    [CommandContribution, KeybindingContribution, MenuContribution].forEach(serviceIdentifier => {
+    [
+        FrontendApplicationContribution,
+        WidgetStatusBarContribution,
+        CommandContribution,
+        KeybindingContribution,
+        MenuContribution
+    ].forEach(serviceIdentifier => {
         bind(serviceIdentifier).toService(EditorContribution);
     });
     bind(QuickEditorService).toSelf().inSingletonScope();

packages/getting-started/src/browser/getting-started-frontend-module.ts

@@ -17,13 +17,14 @@
 import { GettingStartedContribution } from './getting-started-contribution';
 import { ContainerModule, interfaces } from '@theia/core/shared/inversify';
 import { GettingStartedWidget } from './getting-started-widget';
-import { WidgetFactory, FrontendApplicationContribution, bindViewContribution } from '@theia/core/lib/browser';
+import { WidgetFactory, FrontendApplicationContribution, bindViewContribution, noopWidgetStatusBarContribution, WidgetStatusBarContribution } from '@theia/core/lib/browser';
 import { bindGettingStartedPreferences } from './getting-started-preferences';
 import '../../src/browser/style/index.css';
 
 export default new ContainerModule((bind: interfaces.Bind) => {
     bindViewContribution(bind, GettingStartedContribution);
     bind(FrontendApplicationContribution).toService(GettingStartedContribution);
+    bind(WidgetStatusBarContribution).toConstantValue(noopWidgetStatusBarContribution(GettingStartedWidget));
     bind(GettingStartedWidget).toSelf();
     bind(WidgetFactory).toDynamicValue(context => ({
         id: GettingStartedWidget.ID,

packages/keymaps/src/browser/keymaps-frontend-module.ts

@@ -22,7 +22,7 @@ import { KeymapsFrontendContribution } from './keymaps-frontend-contribution';
 import { CommandContribution, MenuContribution } from '@theia/core/lib/common';
 import { KeybindingContribution } from '@theia/core/lib/browser/keybinding';
 import { TabBarToolbarContribution } from '@theia/core/lib/browser/shell/tab-bar-toolbar';
-import { WidgetFactory } from '@theia/core/lib/browser';
+import { noopWidgetStatusBarContribution, WidgetFactory, WidgetStatusBarContribution } from '@theia/core/lib/browser';
 import { KeybindingWidget } from './keybindings-widget';
 import { KeybindingSchemaUpdater } from './keybinding-schema-updater';
 import { JsonSchemaContribution } from '@theia/core/lib/browser/json-schema-store';
@@ -41,4 +41,5 @@ export default new ContainerModule(bind => {
     })).inSingletonScope();
     bind(KeybindingSchemaUpdater).toSelf().inSingletonScope();
     bind(JsonSchemaContribution).toService(KeybindingSchemaUpdater);
+    bind(WidgetStatusBarContribution).toConstantValue(noopWidgetStatusBarContribution(KeybindingWidget));
 });

packages/monaco/src/browser/monaco-frontend-module.ts

@@ -21,7 +21,8 @@ import {
     FrontendApplicationContribution, KeybindingContribution,
     PreferenceService, PreferenceSchemaProvider, createPreferenceProxy,
     PreferenceScope, PreferenceChange, OVERRIDE_PROPERTY_PATTERN, QuickInputService, StylingParticipant, WebSocketConnectionProvider,
-    UndoRedoHandler
+    UndoRedoHandler,
+    WidgetStatusBarContribution
 } from '@theia/core/lib/browser';
 import { TextEditorProvider, DiffNavigatorProvider, TextEditor } from '@theia/editor/lib/browser';
 import { MonacoEditorProvider, MonacoEditorFactory } from './monaco-editor-provider';
@@ -135,7 +136,7 @@ export default new ContainerModule((bind, unbind, isBound, rebind) => {
     bind(FrontendApplicationContribution).toService(MonacoFormattingConflictsContribution);
 
     bind(MonacoStatusBarContribution).toSelf().inSingletonScope();
-    bind(FrontendApplicationContribution).toService(MonacoStatusBarContribution);
+    bind(WidgetStatusBarContribution).toService(MonacoStatusBarContribution);
 
     bind(MonacoCommandRegistry).toSelf().inSingletonScope();
     bind(MonacoEditorCommandHandlers).toSelf().inSingletonScope();