WindowsMenuBarUI.java 文件源码

@Override
protected void installListeners() {
    if (WindowsLookAndFeel.isOnVista()) {
        installWindowListener();
        hierarchyListener =
            new HierarchyListener() {
                public void hierarchyChanged(HierarchyEvent e) {
                    if ((e.getChangeFlags()
                            & HierarchyEvent.DISPLAYABILITY_CHANGED) != 0) {
                        if (menuBar.isDisplayable()) {
                            installWindowListener();
                        } else {
                            uninstallWindowListener();
                        }
                    }
                }
        };
        menuBar.addHierarchyListener(hierarchyListener);
    }
    super.installListeners();
}