Initial modal integration

- Integrate TerminalUI to ViewService and modals
- New Dialog scenario
- Relates #825

spring-shell-core/src/main/java/org/springframework/shell/component/view/TerminalUI.java

@@ -35,6 +35,7 @@ import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.support.MessageBuilder;
 import org.springframework.shell.component.view.control.View;
+import org.springframework.shell.component.view.control.ViewService;
 import org.springframework.shell.component.view.event.DefaultEventLoop;
 import org.springframework.shell.component.view.event.EventLoop;
 import org.springframework.shell.component.view.event.KeyBinder;
@@ -60,7 +61,7 @@ import org.springframework.util.StringUtils;
  *
  * @author Janne Valkealahti
  */
-public class TerminalUI {
+public class TerminalUI implements ViewService {
 
 	private final static Logger log = LoggerFactory.getLogger(TerminalUI.class);
 	private final Terminal terminal;
@@ -70,6 +71,7 @@ public class TerminalUI {
 	private Display display;
 	private Size size;
 	private View rootView;
+	private View modalView;
 	private boolean fullScreen;
 	private final KeyBinder keyBinder;
 	private DefaultEventLoop eventLoop = new DefaultEventLoop();
@@ -87,6 +89,16 @@ public class TerminalUI {
 		this.keyBinder = new KeyBinder(terminal);
 	}
 
+	@Override
+	public View getModal() {
+		return modalView;
+	}
+
+	@Override
+	public void setModal(View view) {
+		this.modalView = view;
+	}
+
 	/**
 	 * Sets a root view.
 	 *
@@ -137,11 +149,15 @@ public class TerminalUI {
 	}
 
 	private void render(int rows, int columns) {
-		if (rootView == null) {
-			return;
+		if (rootView != null) {
+			rootView.setRect(0, 0, columns, rows);
+			rootView.draw(virtualDisplay);
+		}
+		if (modalView != null) {
+			modalView.setLayer(1);
+			modalView.setRect(0, 0, columns, rows);
+			modalView.draw(virtualDisplay);
 		}
-		rootView.setRect(0, 0, columns, rows);
-		rootView.draw(virtualDisplay);
 	}
 
 	private void display() {
@@ -254,8 +270,9 @@ public class TerminalUI {
 
 	private void handleMouseEvent(MouseEvent event) {
 		log.trace("handleMouseEvent {}", event);
-		if (rootView != null) {
-			MouseHandler handler = rootView.getMouseHandler();
+		View view = modalView != null ? modalView : rootView;
+		if (view != null) {
+			MouseHandler handler = view.getMouseHandler();
 			if (handler != null) {
 				MouseHandlerResult result = handler.handle(MouseHandler.argsOf(event));
 				if (result.focus() != null) {

spring-shell-samples/spring-shell-sample-catalog/src/main/java/org/springframework/shell/samples/catalog/Catalog.java

@@ -180,7 +180,7 @@ public class Catalog {
 		eventLoop.onDestroy(eventLoop.viewEvents(LISTVIEW_SCENARIO_TYPEREF, scenarios)
 			.subscribe(event -> {
 				View view = event.args().item().scenario()
-					.configure(eventLoop, themeResolver, activeThemeName)
+					.configure(ui, eventLoop, themeResolver, activeThemeName)
 					.build();
 				component.setRoot(view, true);
 				currentScenarioView = view;
@@ -273,8 +273,12 @@ public class Catalog {
 		return () -> setStyle(style);
 	}
 
+	private void about() {
+	}
+
 	private MenuBarView buildMenuBar(EventLoop eventLoop) {
 		Runnable quitAction = () -> requestQuit();
+		Runnable aboutAction = () -> about();
 		MenuItem[] themeItems = themeResolver.themeNames().stream()
 			.map(tn -> {
 				return MenuItem.of(tn, MenuItemCheckStyle.RADIO, styleAction(tn), "default".equals(tn));
@@ -288,7 +292,7 @@ public class Catalog {
 					themeItems)
 				.setHotKey(Key.t | KeyMask.AltMask),
 			MenuBarItem.of("Help",
-					MenuItem.of("About"))
+					MenuItem.of("About", MenuItemCheckStyle.NOCHECK, aboutAction))
 		);
 
 		menuBar.setThemeResolver(themeResolver);

spring-shell-samples/spring-shell-sample-catalog/src/main/java/org/springframework/shell/samples/catalog/scenario/AbstractScenario.java

@@ -16,6 +16,7 @@
 package org.springframework.shell.samples.catalog.scenario;
 
 import org.springframework.shell.component.view.control.AbstractView;
+import org.springframework.shell.component.view.control.ViewService;
 import org.springframework.shell.component.view.event.EventLoop;
 import org.springframework.shell.style.ThemeResolver;
 
@@ -26,18 +27,24 @@ import org.springframework.shell.style.ThemeResolver;
  */
 public abstract class AbstractScenario implements Scenario {
 
+	private ViewService viewService;
 	private EventLoop eventloop;
 	private ThemeResolver themeResolver;
 	private String themeName;
 
 	@Override
-	public Scenario configure(EventLoop eventloop, ThemeResolver themeResolver, String themeName) {
+	public Scenario configure(ViewService viewService, EventLoop eventloop, ThemeResolver themeResolver, String themeName) {
+		this.viewService = viewService;
 		this.eventloop = eventloop;
 		this.themeResolver = themeResolver;
 		this.themeName = themeName;
 		return this;
 	}
 
+	protected ViewService getViewService() {
+		return viewService;
+	}
+
 	protected EventLoop getEventloop() {
 		return eventloop;
 	}

spring-shell-samples/spring-shell-sample-catalog/src/main/java/org/springframework/shell/samples/catalog/scenario/Scenario.java

@@ -16,6 +16,7 @@
 package org.springframework.shell.samples.catalog.scenario;
 
 import org.springframework.shell.component.view.control.View;
+import org.springframework.shell.component.view.control.ViewService;
 import org.springframework.shell.component.view.event.EventLoop;
 import org.springframework.shell.style.ThemeResolver;
 
@@ -48,6 +49,6 @@ public interface Scenario {
 	 * @param themeName theme name for scenario
 	 * @return scenario for chaining
 	 */
-	Scenario configure(EventLoop eventloop, ThemeResolver themeResolver, String themeName);
+	Scenario configure(ViewService viewService, EventLoop eventloop, ThemeResolver themeResolver, String themeName);
 
 }

spring-shell-samples/spring-shell-sample-catalog/src/main/java/org/springframework/shell/samples/catalog/scenario/other/DialogScenario.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.shell.samples.catalog.scenario.other;
+
+import org.springframework.shell.component.view.control.BoxView;
+import org.springframework.shell.component.view.control.ButtonView;
+import org.springframework.shell.component.view.control.DialogView;
+import org.springframework.shell.component.view.control.View;
+import org.springframework.shell.component.view.geom.HorizontalAlign;
+import org.springframework.shell.component.view.geom.VerticalAlign;
+import org.springframework.shell.samples.catalog.scenario.AbstractScenario;
+import org.springframework.shell.samples.catalog.scenario.Scenario;
+import org.springframework.shell.samples.catalog.scenario.ScenarioComponent;
+
+@ScenarioComponent(name = "Dialog", description = "Modal dialog", category = {
+		Scenario.CATEGORY_OTHER })
+public class DialogScenario extends AbstractScenario {
+
+	private Runnable dialogAction = () -> {
+		DialogView dialog = buildDialog();
+		getViewService().setModal(dialog);
+	};
+
+	@Override
+	public View build() {
+		ButtonView button = new ButtonView("Open Dialog", dialogAction);
+		configure(button);
+		return button;
+	}
+
+	private DialogView buildDialog() {
+		ButtonView button = new ButtonView("OK");
+		configure(button);
+		BoxView content = new BoxView();
+		content.setDrawFunction((screen, rect) -> {
+			screen.writerBuilder().layer(1).build().text("Hello World", rect, HorizontalAlign.CENTER, VerticalAlign.CENTER);
+			return rect;
+		});
+		DialogView dialog = new DialogView(content, button);
+		configure(dialog);
+		dialog.setTransparent(false);
+		dialog.setViewService(getViewService());
+		return dialog;
+	}
+
+}