Add focused color and style for BoxView title

- May define focused color and style for title
  which overrides normal color and style if set.
- Use these in a catalog app.
- Relates #804

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

@@ -48,6 +48,8 @@ public class BoxView extends AbstractView {
 	private Integer backgroundColor = -1;
 	private int titleColor = -1;
 	private int titleStyle = -1;
+	private int focusedTitleColor = -1;
+	private int focusedTitleStyle = -1;
 	private HorizontalAlign titleAlign;
 
 	@Override
@@ -149,6 +151,26 @@ public class BoxView extends AbstractView {
 		this.titleStyle = titleStyle;
 	}
 
+	/**
+	 * Sets a focused title color. Takes precedence set from
+	 * {@link #setTitleColor(int)}.
+	 *
+	 * @param focusedTitleColor the title color
+	 */
+	public void setFocusedTitleColor(int focusedTitleColor) {
+		this.focusedTitleColor = focusedTitleColor;
+	}
+
+	/**
+	 * Sets a focused title style. Takes precedence set from
+	 * {@link #setTitleStyle(int)}.
+	 *
+	 * @param focusedTitleStyle the title style
+	 */
+	public void setFocusedTitleStyle(int focusedTitleStyle) {
+		this.focusedTitleStyle = focusedTitleStyle;
+	}
+
 	/**
 	 * Sets a title align.
 	 *
@@ -180,12 +202,22 @@ public class BoxView extends AbstractView {
 			screen.writerBuilder().layer(getLayer()).build().border(rect.x(), rect.y(), rect.width(), rect.height());
 			if (StringUtils.hasText(title)) {
 				Rectangle r = new Rectangle(rect.x() + 1, rect.y(), rect.width() - 2, 1);
-				if (titleColor > -1) {
-					screen.writerBuilder().layer(getLayer()).color(titleColor).style(titleStyle).build().text(title, r, titleAlign, VerticalAlign.TOP);
+
+				int color = -1;
+				int style = -1;
+				if (hasFocus()) {
+					color = focusedTitleColor;
+					style = focusedTitleStyle;
 				}
-				else {
-					screen.writerBuilder().layer(getLayer()).build().text(title, r, titleAlign, VerticalAlign.TOP);
+				if (color < 0) {
+					color = titleColor;
 				}
+				if (style < 0) {
+					style = titleStyle;
+				}
+
+				screen.writerBuilder().layer(getLayer()).color(color).style(style).build().text(title, r, titleAlign,
+						VerticalAlign.TOP);
 			}
 		}
 		if (getDrawFunction() != null) {

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

@@ -47,6 +47,7 @@ import org.springframework.shell.component.view.geom.Rectangle;
 import org.springframework.shell.component.view.message.ShellMessageBuilder;
 import org.springframework.shell.component.view.screen.Screen;
 import org.springframework.shell.component.view.screen.Screen.Writer;
+import org.springframework.shell.component.view.screen.ScreenItem;
 import org.springframework.shell.samples.catalog.scenario.Scenario;
 import org.springframework.shell.samples.catalog.scenario.ScenarioComponent;
 import org.springframework.util.ObjectUtils;
@@ -196,6 +197,7 @@ public class Catalog {
 		List<String> items = List.copyOf(categoryMap.keySet());
 		categories.setItems(items);
 		categories.setTitle("Categories");
+		categories.setFocusedTitleStyle(ScreenItem.STYLE_BOLD);
 		categories.setShowBorder(true);
 		return categories;
 	}
@@ -215,6 +217,7 @@ public class Catalog {
 		ListView<ScenarioData> scenarios = new ListView<>();
 		scenarios.setEventLoop(eventLoop);
 		scenarios.setTitle("Scenarios");
+		scenarios.setFocusedTitleStyle(ScreenItem.STYLE_BOLD);
 		scenarios.setShowBorder(true);
 		scenarios.setCellFactory(list -> new ScenarioListCell());
 		return scenarios;