Find/Replace overlay: use handler enablement for button enabled state

The enablement of the buttons for search options of the find/replace
overlay are currently derived from the availability of the underlying
search option. However, there are actions attached to the buttons
(changing activation of the search option) and the button enablement
should actually reflect if that action is available or not. Though these
are effectively equal, mapping the button enablement to the action
availability is the conceptually more correct representation.

With this change, FindReplaceOverlayAction extends AbstractHandler,
making the action itself a handler and providing and enablement state.
Enablement of the buttons for the search options is not kept in sync
with enablement of the action/handler via an according handler listener.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: HeikoKlare

bundles/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/findandreplace/overlay/AccessibleToolItem.java

@@ -18,14 +18,16 @@
 import org.eclipse.swt.widgets.ToolBar;
 import org.eclipse.swt.widgets.ToolItem;
 
+import org.eclipse.core.commands.HandlerEvent;
+import org.eclipse.core.commands.IHandlerListener;
+
 import org.eclipse.jface.layout.GridDataFactory;
 
 class AccessibleToolItem {
 	private final ToolItem toolItem;
 
 	private String baseToolTipText;
 
-
 	AccessibleToolItem(Composite parent, int styleBits) {
 		ToolBar toolbar = new ToolBar(parent, SWT.FLAT | SWT.HORIZONTAL);
 		GridDataFactory.fillDefaults().grab(true, true).align(SWT.CENTER, SWT.CENTER).applyTo(toolbar);
@@ -51,6 +53,15 @@ void setToolTipText(String text) {
 
 	void setAction(FindReplaceOverlayAction action) {
 		setToolTipText(toolItem.getToolTipText());
+		toolItem.setEnabled(action.isEnabled());
+		action.addHandlerListener(new IHandlerListener() {
+			@Override
+			public void handlerChanged(HandlerEvent event) {
+				if (event.isEnabledChanged() && !toolItem.isDisposed()) {
+					toolItem.setEnabled(action.isEnabled());
+				}
+			}
+		});
 		toolItem.addSelectionListener(SelectionListener.widgetSelectedAdapter(__ -> action.execute()));
 		action.addShortcutHintListener(hint -> {
 			if (!toolItem.isDisposed()) {

bundles/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/findandreplace/overlay/AccessibleToolItemBuilder.java

@@ -104,12 +104,8 @@ public ToolItem build() {
 					toolItem.setSelection(invertSearchOption ? !state : state);
 				}
 			});
-			toolItem.setEnabled(findReplaceLogic.isAvailable(searchOption));
-			findReplaceLogic.addSearchOptionAvailabilityChangedListener(searchOption, state -> {
-				if (!toolItem.isDisposed()) {
-					toolItem.setEnabled(state);
-				}
-			});
+			searchOptionAction.setAvailable(findReplaceLogic.isAvailable(searchOption));
+			findReplaceLogic.addSearchOptionAvailabilityChangedListener(searchOption, searchOptionAction::setAvailable);
 			return toolItem;
 		}
 	}

bundles/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/findandreplace/overlay/FindReplaceOverlayAction.java

@@ -15,9 +15,12 @@
 import java.util.List;
 import java.util.function.Consumer;
 
+import org.eclipse.core.commands.AbstractHandler;
+import org.eclipse.core.commands.ExecutionEvent;
+
 import org.eclipse.jface.bindings.keys.KeyStroke;
 
-class FindReplaceOverlayAction {
+class FindReplaceOverlayAction extends AbstractHandler {
 	private final Runnable operation;
 
 	private final List<Runnable> executionListeners = new ArrayList<>();
@@ -34,11 +37,21 @@ void addShortcuts(List<KeyStroke> shortcutsToAdd) {
 		this.shortcuts.addAll(shortcutsToAdd);
 	}
 
+	@Override
+	public Object execute(ExecutionEvent event) {
+		execute();
+		return null;
+	}
+
 	void execute() {
 		operation.run();
 		notifyExecutionListeners();
 	}
 
+	void setAvailable(boolean available) {
+		setBaseEnabled(available);
+	}
+
 	List<KeyStroke> getShortcuts() {
 		return Collections.unmodifiableList(shortcuts);
 	}