Add property on rootpane to hide titlebar. Fixes #211

core/src/main/java/com/github/weisj/darklaf/ui/rootpane/DarkRootPaneUI.java

@@ -41,6 +41,7 @@ import com.github.weisj.darklaf.util.PropertyUtil;
 public class DarkRootPaneUI extends BasicRootPaneUI implements HierarchyListener {
 
     protected static final String KEY_PREFIX = "JRootPane.";
+    public static final String HIDE_TITLEBAR = KEY_PREFIX + "hideTitleBar";
     public static final String KEY_NO_DECORATIONS_UPDATE = KEY_PREFIX + "noDecorationsUpdate";
     public static final String KEY_NO_DECORATIONS = KEY_PREFIX + "noDecorations";
     public static final String KEY_UNIFIED_MENUBAR = KEY_PREFIX + "unifiedMenuBar";

macos/src/main/java/com/github/weisj/darklaf/platform/macos/ui/MacOSTitlePane.java

@@ -33,6 +33,7 @@ import javax.swing.*;
 import com.github.weisj.darklaf.platform.decorations.CustomTitlePane;
 import com.github.weisj.darklaf.platform.macos.JNIDecorationsMacOS;
 import com.github.weisj.darklaf.util.PropertyKey;
+import com.github.weisj.darklaf.util.PropertyUtil;
 
 public class MacOSTitlePane extends CustomTitlePane {
 
@@ -47,12 +48,15 @@ public class MacOSTitlePane extends CustomTitlePane {
     private DecorationInformation decorationInformation;
     private JLabel titleLabel;
     private PropertyChangeHandler propertyChangeListener;
+    private PropertyChangeListener rootPanePropertyChangeListener;
+    private boolean titleBarHidden;
     private boolean hideTitleBar = false;
 
     public MacOSTitlePane(final JRootPane rootPane, final Window window) {
         this.rootPane = rootPane;
         this.window = window;
         determineColors();
+        updateTitleBarVisibility();
     }
 
     protected void determineColors() {
@@ -151,6 +155,8 @@ public class MacOSTitlePane extends CustomTitlePane {
             window.addWindowListener(windowListener);
             propertyChangeListener = new PropertyChangeHandler();
             window.addPropertyChangeListener(propertyChangeListener);
+            rootPanePropertyChangeListener = createRootPanePropertyChangeListener();
+            rootPane.addPropertyChangeListener(rootPanePropertyChangeListener);
         }
     }
 
@@ -161,6 +167,24 @@ public class MacOSTitlePane extends CustomTitlePane {
             window.removePropertyChangeListener(propertyChangeListener);
             propertyChangeListener = null;
         }
+        if (rootPane != null) {
+            rootPane.removePropertyChangeListener(rootPanePropertyChangeListener);
+            rootPanePropertyChangeListener = null;
+        }
+    }
+
+    private PropertyChangeListener createRootPanePropertyChangeListener() {
+        return new RootPanePropertyChangeListener();
+    }
+
+    protected class RootPanePropertyChangeListener implements PropertyChangeListener {
+
+        @Override
+        public void propertyChange(final PropertyChangeEvent evt) {
+            if ("JRootPane.hideTitleBar".equals(evt.getPropertyName())) {
+                updateTitleBarVisibility();
+            }
+        }
     }
 
     @Override
@@ -186,11 +210,19 @@ public class MacOSTitlePane extends CustomTitlePane {
     }
 
     private boolean hideTitleBar() {
+        if (titleBarHidden) return true;
         return (decorationInformation.windowHandle == 0)
                 || JNIDecorationsMacOS.isFullscreen(decorationInformation.windowHandle)
                 || getDecorationStyle() == JRootPane.NONE;
     }
 
+
+    private void updateTitleBarVisibility() {
+        titleBarHidden = PropertyUtil.getBooleanProperty(rootPane, "JRootPane.hideTitleBar");
+        rootPane.doLayout();
+        rootPane.repaint();
+    }
+
     private boolean useCustomTitle() {
         return titleLabel != null && decorationInformation != null && !decorationInformation.titleVisible;
     }

windows/src/main/java/com/github/weisj/darklaf/platform/windows/ui/WindowsTitlePane.java

@@ -56,6 +56,7 @@ public class WindowsTitlePane extends CustomTitlePane {
     private final JRootPane rootPane;
 
     private boolean unifiedMenuBar;
+    private boolean titleBarHidden;
     private ContainerListener rootPaneContainerListener;
     private ContainerListener layeredPaneContainerListener;
 
@@ -105,6 +106,7 @@ public class WindowsTitlePane extends CustomTitlePane {
         oldResizable = true;
         installSubcomponents();
         updateMenuBar(true);
+        updateTitleBarVisibility();
         installDefaults();
         setLayout(createLayout());
     }
@@ -133,6 +135,12 @@ public class WindowsTitlePane extends CustomTitlePane {
         rootPane.revalidate();
     }
 
+    private void updateTitleBarVisibility() {
+        titleBarHidden = PropertyUtil.getBooleanProperty(rootPane, "JRootPane.hideTitleBar");
+        rootPane.doLayout();
+        rootPane.repaint();
+    }
+
     private ContainerListener createRootPaneContainerListener() {
         return new ContainerListener() {
             @Override
@@ -247,6 +255,9 @@ public class WindowsTitlePane extends CustomTitlePane {
             determineColors();
             setActive(window.isActive());
             installListeners();
+            if (getComponentCount() == 0) {
+                addComponents();
+            }
             updateSystemIcon(getGraphicsConfiguration());
         }
     }
@@ -305,16 +316,20 @@ public class WindowsTitlePane extends CustomTitlePane {
     private void installSubcomponents() {
         titleLabel = new JLabel();
         titleLabel.setHorizontalAlignment(JLabel.LEFT);
-        add(titleLabel);
 
         createIcons();
         createActions();
         createButtons();
 
+        addComponents();
+    }
+
+    private void addComponents() {
         add(windowIconButton);
         add(minimizeButton);
         add(maximizeToggleButton);
         add(closeButton);
+        add(titleLabel);
         setComponentZOrder(closeButton, 0);
         setComponentZOrder(maximizeToggleButton, 1);
         setComponentZOrder(minimizeButton, 2);
@@ -697,14 +712,14 @@ public class WindowsTitlePane extends CustomTitlePane {
     }
 
     private boolean hideTitleBar() {
+        if (titleBarHidden) return true;
         String title = titleLabel.getText();
         if (title == null) title = "";
-        return windowHandle == 0 || (getDecorationStyle() == JRootPane.NONE && (menuBar == null || !menuBar.isVisible())
-                && title.length() == 0)
         // e.g. VCLJ achieves fullscreen by hiding the titlebar through jni and setting visibility
-        // of
-        // the menubar.
-                || (menuBar != null && !menuBar.isVisible());
+        // of the menubar.
+        boolean emptyMenuBar = !unifiedMenuBar || menuBar == null || !menuBar.isVisible();
+        boolean emptyContent = getDecorationStyle() == JRootPane.NONE && emptyMenuBar && title.length() == 0;
+        return windowHandle == 0 || emptyContent || (menuBar != null && !menuBar.isVisible());
     }
 
     @Override
@@ -905,6 +920,8 @@ public class WindowsTitlePane extends CustomTitlePane {
         public void propertyChange(final PropertyChangeEvent evt) {
             if ("JRootPane.unifiedMenuBar".equals(evt.getPropertyName())) {
                 updateMenuBar(true);
+            } else if ("JRootPane.hideTitleBar".equals(evt.getPropertyName())) {
+                updateTitleBarVisibility();
             }
         }
     }