Module java.desktop
Package java.awt

# Class MenuBar

java.lang.Object
java.awt.MenuComponent
java.awt.MenuBar

All Implemented Interfaces:
  `MenuContainer`, `Serializable`, `Accessible`

public class MenuBar extends MenuComponent implements MenuContainer, Accessible
The `MenuBar` class encapsulates the platform's concept of a menu bar bound to a frame. In order to associate the menu bar with a `Frame` object, call the frame's `setMenuBar` method.

This is what a menu bar might look like:

A menu bar handles keyboard shortcuts for menu items, passing them along to its child menus. (Keyboard shortcuts, which are optional, provide the user with an alternative to the mouse for invoking a menu item and the action that is associated with it.) Each menu item can maintain an instance of `MenuShortcut`. The `MenuBar` class defines several methods, `shortcuts()` and `getShortcutMenuItem(java.awt.MenuShortcut)` that retrieve information about the shortcuts a given menu bar is managing.

Since:
  1.0
See Also:
  - `Frame`
  - `Frame.setMenuBar(java.awt.MenuBar)`
  - `Menu`
  - `MenuItem`
  - `MenuShortcut`
  - Serialized Form

## Nested Class Summary

Nested Classes
Modifier and Type
Class
Description
`protected class`
`MenuBar.AccessibleAWTMenuBar`
Inner class of MenuBar used to provide default support for accessibility.

## Nested classes/interfaces declared in class java.awt.MenuComponent

`MenuComponent.AccessibleAWTMenuComponent`

## Constructor Summary

Constructors
Constructor
Description
`MenuBar()`
Creates a new menu bar.

## Method Summary

Modifier and Type
Method
Description
`Menu`
`add(Menu m)`
Adds the specified menu to the menu bar.
`void`
`addNotify()`
Creates the menu bar's peer.
`int`
`countMenus()`
Deprecated.
As of JDK version 1.1, replaced by `getMenuCount()`.
`void`
`deleteShortcut(MenuShortcut s)`
Deletes the specified menu shortcut.
`AccessibleContext`
`getAccessibleContext()`
Gets the AccessibleContext associated with this MenuBar.
`Menu`
`getHelpMenu()`
Gets the help menu on the menu bar.
`Menu`
`getMenu(int i)`
Gets the specified menu.
`int`
`getMenuCount()`
Gets the number of menus on the menu bar.
`MenuItem`
`getShortcutMenuItem(MenuShortcut s)`
Gets the instance of `MenuItem` associated with the specified `MenuShortcut` object, or `null` if none of the menu items being managed by this menu bar is associated with the specified menu shortcut.
`void`
`remove(int index)`
Removes the menu located at the specified index from this menu bar.
`void`
`remove(MenuComponent m)`
Removes the specified menu component from this menu bar.
`void`
`removeNotify()`
Removes the menu bar's peer.
`void`
`setHelpMenu(Menu m)`
Sets the specified menu to be this menu bar's help menu.
`Enumeration<MenuShortcut>`
`shortcuts()`
Gets an enumeration of all menu shortcuts this menu bar is managing.

### Methods declared in class java.awt.MenuComponent

`dispatchEvent, getFont, getName, getParent, getTreeLock, paramString, postEvent, processEvent, setFont, setName, toString`

### Methods declared in class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

### Methods declared in interface java.awt.MenuContainer

`getFont, postEvent`

## Constructor Details

### MenuBar

public MenuBar() throws HeadlessException
Creates a new menu bar.

Throws:
  `HeadlessException` - if GraphicsEnvironment.isHeadless() returns true.
See Also:
  - `GraphicsEnvironment.isHeadless()`

## Method Details

### addNotify

public void addNotify()
Creates the menu bar's peer. The peer allows us to change the appearance of the menu bar without changing any of the menu bar's functionality.

### removeNotify

public void removeNotify()
Removes the menu bar's peer. The peer allows us to change the appearance of the menu bar without changing any of the menu bar's functionality.

Overrides:
  `removeNotify` in class `MenuComponent`

### getHelpMenu

public Menu getHelpMenu()
Gets the help menu on the menu bar.

Returns:
  the help menu on this menu bar.

### setHelpMenu

public void setHelpMenu(Menu m)
Sets the specified menu to be this menu bar's help menu. If this menu bar has an existing help menu, the old help menu is removed from the menu bar, and replaced with the specified menu.

Parameters:
  `m` - the menu to be set as the help menu

### add

public Menu add(Menu m)
Adds the specified menu to the menu bar. If the menu has been part of another menu bar, removes it from that menu bar.

Parameters:
  `m` - the menu to be added
Returns:
  the menu added
See Also:
  - `remove(int)`
  - `remove(java.awt.MenuComponent)`

### remove

public void remove(int index)
Removes the menu located at the specified index from this menu bar.

Parameters:
  `index` - the position of the menu to be removed.
See Also:
  - `add(java.awt.Menu)`

### remove

public void remove(MenuComponent m)
Removes the specified menu component from this menu bar.

Specified by:
  `remove` in interface `MenuContainer`
Parameters:
  `m` - the menu component to be removed.
See Also:
  - `add(java.awt.Menu)`

### getMenuCount

public int getMenuCount()
Gets the number of menus on the menu bar.

Returns:
  the number of menus on the menu bar.
Since:
  1.1

### countMenus

@Deprecated public int countMenus()
Deprecated.
As of JDK version 1.1, replaced by `getMenuCount()`.
Gets the number of menus on the menu bar.

Returns:
  the number of menus on the menu bar.

### getMenu

public Menu getMenu(int i)
Gets the specified menu.

Parameters:
  `i` - the index position of the menu to be returned.
Returns:
  the menu at the specified index of this menu bar.

### shortcuts

public Enumeration<MenuShortcut> shortcuts()
Gets an enumeration of all menu shortcuts this menu bar is managing.

Returns:
  an enumeration of menu shortcuts that this menu bar is managing.
Since:
  1.1
See Also:
  - `MenuShortcut`

### getShortcutMenuItem

public MenuItem getShortcutMenuItem(MenuShortcut s)
Gets the instance of `MenuItem` associated with the specified `MenuShortcut` object, or `null` if none of the menu items being managed by this menu bar is associated with the specified menu shortcut.

Parameters:
  `s` - the specified menu shortcut.
Returns:
  the menu item for the specified shortcut.
Since:
  1.1
See Also:
  - `MenuItem`
  - `MenuShortcut`

### deleteShortcut

public void deleteShortcut(MenuShortcut s)
Deletes the specified menu shortcut.

Parameters:
  `s` - the menu shortcut to delete.
Since:
  1.1

### getAccessibleContext

public AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this MenuBar. For menu bars, the AccessibleContext takes the form of an AccessibleAWTMenuBar. A new AccessibleAWTMenuBar instance is created if necessary.

Specified by:
  `getAccessibleContext` in interface `Accessible`
Overrides:
  `getAccessibleContext` in class `MenuComponent`
Returns:
  an AccessibleAWTMenuBar that serves as the AccessibleContext of this MenuBar
Since:
  1.3