TabbedPane: fixed actions scrollTabsForwardAction and scrollTabsBackwardAction when used from outside (e.g. in NetBeans)

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTabbedPaneUI.java

@@ -58,6 +58,8 @@ import java.util.function.BiConsumer;
 import java.util.function.IntConsumer;
 import javax.accessibility.Accessible;
 import javax.accessibility.AccessibleContext;
+import javax.swing.Action;
+import javax.swing.ActionMap;
 import javax.swing.ButtonModel;
 import javax.swing.Icon;
 import javax.swing.JButton;
@@ -490,6 +492,20 @@ public class FlatTabbedPaneUI
 		}
 	}
 
+	@Override
+	protected void installKeyboardActions() {
+		super.installKeyboardActions();
+
+		// get shared action map, used for all tabbed panes
+		ActionMap map = SwingUtilities.getUIActionMap( tabPane );
+		if( map != null ) {
+			// this is required for the case that those actions are used from outside
+			// (e.g. wheel tab scroller in NetBeans)
+			RunWithOriginalLayoutManagerDelegateAction.install( map, "scrollTabsForwardAction" );
+			RunWithOriginalLayoutManagerDelegateAction.install( map, "scrollTabsBackwardAction" );
+		}
+	}
+
 	private Handler getHandler() {
 		if( handler == null )
 			handler = new Handler();
@@ -2959,4 +2975,51 @@ public class FlatTabbedPaneUI
 			scrollBackwardButtonPrefSize = backwardButton.getPreferredSize();
 		}
 	}
+
+	//---- class RunWithOriginalLayoutManagerDelegateAction -------------------
+
+	private static class RunWithOriginalLayoutManagerDelegateAction
+		implements Action
+	{
+		private final Action delegate;
+
+		static void install( ActionMap map, String key ) {
+			Action oldAction = map.get( key );
+			if( oldAction == null || oldAction instanceof RunWithOriginalLayoutManagerDelegateAction )
+				return; // not found or already installed
+
+			map.put( key, new RunWithOriginalLayoutManagerDelegateAction( oldAction ) );
+		}
+
+		private RunWithOriginalLayoutManagerDelegateAction( Action delegate ) {
+			this.delegate = delegate;
+		}
+
+		@Override
+		public Object getValue( String key ) {
+			return delegate.getValue( key );
+		}
+
+		@Override
+		public boolean isEnabled() {
+			return delegate.isEnabled();
+		}
+
+		@Override public void putValue( String key, Object value ) {}
+		@Override public void setEnabled( boolean b ) {}
+		@Override public void addPropertyChangeListener( PropertyChangeListener listener ) {}
+		@Override public void removePropertyChangeListener( PropertyChangeListener listener ) {}
+
+		@Override
+		public void actionPerformed( ActionEvent e ) {
+			JTabbedPane tabbedPane = (JTabbedPane) e.getSource();
+			ComponentUI ui = tabbedPane.getUI();
+			if( ui instanceof FlatTabbedPaneUI ) {
+				((FlatTabbedPaneUI)ui).runWithOriginalLayoutManager( () -> {
+					delegate.actionPerformed( e );
+				} );
+			} else
+				delegate.actionPerformed( e );
+		}
+	}
 }

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatContainerTest.java

@@ -18,7 +18,10 @@ package com.formdev.flatlaf.testing;
 
 import static com.formdev.flatlaf.FlatClientProperties.*;
 import java.awt.*;
+import java.awt.event.ActionEvent;
 import java.awt.event.MouseEvent;
+import java.awt.event.MouseWheelEvent;
+import java.awt.event.MouseWheelListener;
 import javax.swing.*;
 import javax.swing.border.*;
 import com.formdev.flatlaf.FlatLaf;
@@ -418,6 +421,32 @@ public class FlatContainerTest
 			tabbedPane.setMaximumTabWidth( maximumTabWidth );
 	}
 
+	private void customWheelScrollingChanged() {
+		if( custoMouseWheelScroller != null ) {
+			for( FlatTabbedPane tabbedPane : allTabbedPanes )
+				tabbedPane.removeMouseWheelListener( custoMouseWheelScroller );
+			custoMouseWheelScroller = null;
+		}
+
+		if( customWheelScrollingCheckBox.isSelected() ) {
+			custoMouseWheelScroller = new MouseWheelListener() {
+				@Override
+				public void mouseWheelMoved( MouseWheelEvent e ) {
+					if( e.getScrollType() == MouseWheelEvent.WHEEL_UNIT_SCROLL ) {
+						JTabbedPane tabbedPane = (JTabbedPane) e.getComponent();
+						ActionMap actionMap = tabbedPane.getActionMap();
+						Action scrollAction = actionMap.get( (e.getWheelRotation() < 0)
+							? "scrollTabsBackwardAction" : "scrollTabsForwardAction" );
+						if( scrollAction != null && scrollAction.isEnabled() )
+							scrollAction.actionPerformed( new ActionEvent( tabbedPane, 0, "" ) );
+					}
+				}
+			};
+			for( FlatTabbedPane tabbedPane : allTabbedPanes )
+				tabbedPane.addMouseWheelListener( custoMouseWheelScroller );
+		}
+	}
+
 	private void initComponents() {
 		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
 		JPanel panel9 = new JPanel();
@@ -475,6 +504,7 @@ public class FlatContainerTest
 		showTabSeparatorsCheckBox = new JCheckBox();
 		secondTabWiderCheckBox = new JCheckBox();
 		hideTabAreaWithOneTabCheckBox = new JCheckBox();
+		customWheelScrollingCheckBox = new JCheckBox();
 		CellConstraints cc = new CellConstraints();
 
 		//======== this ========
@@ -773,6 +803,11 @@ public class FlatContainerTest
 				hideTabAreaWithOneTabCheckBox.setText("Hide tab area with one tab");
 				hideTabAreaWithOneTabCheckBox.addActionListener(e -> hideTabAreaWithOneTabChanged());
 				tabbedPaneControlPanel.add(hideTabAreaWithOneTabCheckBox, "cell 1 10");
+
+				//---- customWheelScrollingCheckBox ----
+				customWheelScrollingCheckBox.setText("Custom wheel scrolling");
+				customWheelScrollingCheckBox.addActionListener(e -> customWheelScrollingChanged());
+				tabbedPaneControlPanel.add(customWheelScrollingCheckBox, "cell 2 10");
 			}
 			panel9.add(tabbedPaneControlPanel, cc.xywh(1, 11, 3, 1));
 		}
@@ -818,9 +853,11 @@ public class FlatContainerTest
 	private JCheckBox showTabSeparatorsCheckBox;
 	private JCheckBox secondTabWiderCheckBox;
 	private JCheckBox hideTabAreaWithOneTabCheckBox;
+	private JCheckBox customWheelScrollingCheckBox;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 
 	private FlatTabbedPane[] allTabbedPanes;
+	private MouseWheelListener custoMouseWheelScroller;
 
 	//---- enum TabPlacement --------------------------------------------------
 

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatContainerTest.jfd

@@ -1,4 +1,4 @@
-JFDML JFormDesigner: "7.0.2.0.298" Java: "15" encoding: "UTF-8"
+JFDML JFormDesigner: "7.0.3.1.342" Java: "16" encoding: "UTF-8"
 
 new FormModel {
 	contentType: "form/swing"
@@ -502,6 +502,16 @@ new FormModel {
 					}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 						"value": "cell 1 10"
 					} )
+					add( new FormComponent( "javax.swing.JCheckBox" ) {
+						name: "customWheelScrollingCheckBox"
+						"text": "Custom wheel scrolling"
+						auxiliary() {
+							"JavaCodeGenerator.variableLocal": false
+						}
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "customWheelScrollingChanged", false ) )
+					}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+						"value": "cell 2 10"
+					} )
 				}, new FormLayoutConstraints( class com.jgoodies.forms.layout.CellConstraints ) {
 					"gridY": 11
 					"gridWidth": 3