Tooltip for a JMenuItem

问题:

I add a menu to a toolbar like this :

    JMenuBar menu = new JMenuBar();
    JMenu actions = new JMenu("Aktionen");
    Icon menuIcon = ImageUtilities.loadImageIcon("pathToIcon", true);
    actions.setIcon(menuIcon);

    // Add
    JMenuItem addItem = new JMenuItem("Add");       
    Icon addIcon = ImageUtilities.loadImageIcon("pathToIcon", true);
    addItem.setIcon(addIcon);
    addItem.setToolTipText("Add new Item");
    addItem.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            AddItemAction someAction = new AddItemAction();
            someAction.actionPerformed(new ActionEvent(this, ActionEvent.ACTION_PERFORMED, null) {
                // Foo
            });
        }
    });        

    menu.add(actions);
    actions.add(addItem);
    toolbar.addSeparator();
    toolbar.add(menu);  

Basically, it works fine. But, it never displays the tooltip ("Add new Item"). Any hints ?

EDIT: Just in case someone with the same problem stumbles upon this: it was the L&F, as I should have suspected from the beginning. It has a property for displaying tooltips of JMenuItems ; and it defaults to false.

回答1:

The sscce below works correctly. If you still have problems, please edit your question to include an example that exhibits the problem you describe.

Addendum: I added the menu to a JToolBar, and it still works, either docked or free-floating.

import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JToolBar;

/** @see http://stackoverflow.com/a/14630345/230513 */
public class Test {

    private void display() {
        JFrame f = new JFrame("Test");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JMenuBar menu = new JMenuBar();
        JMenu actions = new JMenu("Aktionen");
        JMenuItem addItem = new JMenuItem("Add");
        addItem.setToolTipText("Add new Item");
        menu.add(actions);
        actions.add(addItem);
        JToolBar toolbar = new JToolBar("Tools");
        toolbar.add(menu);
        f.add(toolbar);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new Test().display();
            }
        });
    }
}