SwingX: JXHeader support (#8)

flatlaf-swingx/src/main/java/com/formdev/flatlaf/swingx/ui/FlatHeaderUI.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2019 FormDev Software GmbH
+ *
+ * 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
+ *
+ *     http://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 com.formdev.flatlaf.swingx.ui;
+
+import java.awt.Component;
+import java.awt.GridBagConstraints;
+import java.awt.GridBagLayout;
+import java.awt.LayoutManager;
+import javax.swing.JComponent;
+import javax.swing.plaf.ComponentUI;
+import org.jdesktop.swingx.JXHeader;
+import org.jdesktop.swingx.plaf.basic.BasicHeaderUI;
+import com.formdev.flatlaf.util.UIScale;
+
+/**
+ * Provides the Flat LaF UI delegate for {@link org.jdesktop.swingx.JXHeader}.
+ *
+ * @author Karl Tauber
+ */
+public class FlatHeaderUI
+	extends BasicHeaderUI
+{
+	public static ComponentUI createUI( JComponent c ) {
+		return new FlatHeaderUI();
+	}
+
+	@Override
+	protected void installComponents( JXHeader header ) {
+		super.installComponents( header );
+
+		scaleLayout( header );
+	}
+
+	@Override
+	protected void onPropertyChange( JXHeader h, String propertyName, Object oldValue, Object newValue ) {
+		super.onPropertyChange( h, propertyName, oldValue, newValue );
+
+		if( "iconPosition".equals( propertyName ) )
+			scaleLayout( h );
+	}
+
+	private void scaleLayout( JXHeader header ) {
+		if( UIScale.getUserScaleFactor() == 1f )
+			return;
+
+		LayoutManager layout = header.getLayout();
+		if( !(layout instanceof GridBagLayout) )
+			return;
+
+		GridBagLayout gbl = (GridBagLayout) layout;
+		for( Component c : header.getComponents() ) {
+			GridBagConstraints cons = gbl.getConstraints( c );
+			cons.insets = UIScale.scale( cons.insets );
+			gbl.setConstraints( c, cons );
+		}
+	}
+}