* For the keyboard keys used by this component in the standard Look and * Feel (L&F) renditions, see the * JMenuBar key assignments. *
* Warning: serialized objects of this class will not be compatible with
* future swing releases. The current serialization support is appropriate
* for short term storage or RMI between Swing1.0 applications. It will
* not be possible to load serialized Swing1.0 objects with future releases
* of Swing. The JDK1.2 release of Swing will be the compatibility
* baseline for the serialized form of Swing objects.
*
* @version 1.52 04/09/98
* @author Georges Saab
* @author David Karlton
* @author Arnaud Weber
* @see JMenu
* @see JPopupMenu
* @see JMenuItem
*/
public class JMenuBar extends JComponent implements Accessible,MenuElement
{
/*
* Model for the selected subcontrol
*/
private transient SingleSelectionModel selectionModel;
private boolean paintBorder = true;
private Insets margin = null;
/**
* Creates a new menu bar.
*/
public JMenuBar() {
super();
setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
setSelectionModel(new DefaultSingleSelectionModel());
updateUI();
}
/**
* Returns the menubar's current UI.
* @see setUI
*/
public MenuBarUI getUI() {
return (MenuBarUI)ui;
}
/**
* Sets the L&F object that renders this component.
*
* @param ui the new MenuBarUI L&F object
* @see UIDefaults#getUI
*/
public void setUI(MenuBarUI ui) {
super.setUI(ui);
}
/**
* Notification from the UIFactory that the L&F has changed.
* Called to replace the UI with the latest version from the
* UIFactory.
*
* @see JComponent#updateUI
*/
public void updateUI() {
setUI((MenuBarUI)UIManager.getUI(this));
}
/**
* Returns the name of the L&F class that renders this component.
*
* @return "MenuBarUI"
* @see JComponent#getUIClassID
* @see UIDefaults#getUI
*/
public String getUIClassID() {
return "MenuBarUI";
}
/**
* Returns the model object that handles single selections.
*
* @return the SingleSelectionModel in use
* @see SingleSelectionModel
*/
public SingleSelectionModel getSelectionModel() {
return selectionModel;
}
/**
* Set the model object to handle single selections.
*
* @param model the SingleSelectionModel to use
* @see SingleSelectionModel
*/
public void setSelectionModel(SingleSelectionModel model) {
final JMenuBar thisMenuBar = this;
selectionModel = model;
}
/**
* Appends the specified menu to the end of the menu bar.
*
* @param c the JMenu component to add
*/
public JMenu add(JMenu c) {
Dimension size = c.getSize();
size.height = Short.MAX_VALUE;
// c.setMaximumSize(size);
super.add(c);
getUI().registerMenu(c);
return c;
}
/**
* Gets the menu at the specified position in the menu bar.
*
* @param index an int giving the position in the menu bar, where
* 0 is the first position
* @return the JMenu at that position
*/
public JMenu getMenu(int index) {
Component c = getComponentAtIndex(index);
if (c instanceof JMenu)
return (JMenu) c;
return null;
}
/**
* Returns the number of items in the menu bar.
*
* @return the number of items in the menu bar
*/
public int getMenuCount() {
return getComponentCount();
}
/**
* Removes the component at the specified index.
*
* @param index an int specifying the menu bar position, where 0 = first
*/
public void remove(int index) {
Component c = getComponent(index);
if(c instanceof JMenu)
getUI().unregisterMenu((JMenu)c);
super.remove(index);
}
/**
* Sets the help menu that appears when the user selects the
* "help" option in the menu bar.
*
* @param menu the JMenu that delivers help to the user
*/
public void setHelpMenu(JMenu menu) {
throw new Error("setHelpMenu() not yet implemented.");
}
/**
* Gets the help menu for the menu bar.
*
* @return the JMenu that delivers help to the user
*/
public JMenu getHelpMenu() {
throw new Error("getHelpMenu() not yet implemented.");
}
/**
* Returns the component at the specified index.
*
* @param i an int specifying the position, where 0 = first
* @return the Component at the position, or null for an
* invalid index
*/
public Component getComponentAtIndex(int i) {
int ncomponents = this.getComponentCount();
if (i <= ncomponents) {
Component[] component = this.getComponents();
return component[i];
}
return null;
}
/**
* Returns the index of the specified component.
*
* @param c the Component to find
* @return an int giving the component's position, where 0 = first
*/
public int getComponentIndex(Component c) {
int ncomponents = this.getComponentCount();
Component[] component = this.getComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = component[i];
if (comp == c)
return i;
}
return -1;
}
/**
* Sets the currently selected component, producing a
* a change to the selection model.
*
* @param sel the Component to select
*/
public void setSelected(Component sel) {
SingleSelectionModel model = getSelectionModel();
int index = getComponentIndex(sel);
model.setSelectedIndex(index);
}
/**
* Returns true if the MenuBar currently has a component selected
*
* @return true if a selection has been made, else false
*/
public boolean isSelected() {
return selectionModel.isSelected();
}
/**
* Returns true if a the Menubar's border should be painted.
*
* @return true if the border should be painted, else false
*/
public boolean isBorderPainted() {
return paintBorder;
}
/**
* Determines whether the MenuBar's current border will be painted.
*
* @param s true if the border should be painted, else false
*/
public void setBorderPainted(boolean s) {
paintBorder = s;
}
/**
* Paint the menubar's border if BorderPainted property is true.
*
* @param g the Graphics context to use for painting
* @see JComponent#paint
* @see JComponent#setBorder
*/
protected void paintBorder(Graphics g) {
if (isBorderPainted()) {
super.paintBorder(g);
}
}
/**
* Sets the margin between the menubar's border and
* its menus. Setting to null will cause the menubar to
* use the default margins.
*
* @param margin an Insets object containing the margin values
* @see Insets
*/
public void setMargin(Insets margin) {
this.margin = margin;
invalidate();
}
/**
* Returns the margin between the menubar's border and
* its menus.
*
* @return an Insets object containing the margin values
* @see Insets
*/
public Insets getMargin() {
if(margin == null) {
return new Insets(0,0,0,0);
} else {
return margin;
}
}
/**
* Implemented to be a MenuElement -- does nothing.
*
* @see #getSubElements
*/
public void processMouseEvent(MouseEvent event,MenuElement path[],MenuSelectionManager manager) {
}
/**
* Implemented to be a MenuElement -- does nothing.
*
* @see #getSubElements
*/
public void processKeyEvent(KeyEvent e,MenuElement path[],MenuSelectionManager manager) {
}
/**
* Implemented to be a MenuElement -- does nothing.
*
* @see #getSubElements
*/
public void menuSelectionChanged(boolean isIncluded) {
}
/**
* Implemented to be a MenuElement -- returns the menus in this menu
* bar. This is the reason for implementing the MenuElement
* interface -- so that the menu bar can be treated the same as
* other menu elements.
*/
public MenuElement[] getSubElements() {
int menuCount = getMenuCount();
int i;
MenuElement result[] = new MenuElement[menuCount];
for(i=0;i