Java Module java.desktop Package java.awt Class MenuBar（JDK11）

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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

All Methods Instance Methods Concrete Methods Deprecated Methods
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 Detail
  - MenuBar
```
public MenuBar()
        throws HeadlessException
```
    Creates a new menu bar.
    
    Throws:
    
    HeadlessException - if GraphicsEnvironment.isHeadless() returns true.
    
    See Also:
    
    GraphicsEnvironment.isHeadless()
- Method Detail
  - 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

Java Module java.desktop Package java.awt Class MenuBar（JDK11）

Class MenuBar

Nested Class Summary

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

Constructor Summary

Method Summary

Methods declared in class java.awt.MenuComponent

Methods declared in class java.lang.Object

Methods declared in interface java.awt.MenuContainer

Constructor Detail

MenuBar

Method Detail

addNotify

removeNotify

getHelpMenu

setHelpMenu

add

remove

remove

getMenuCount

countMenus

getMenu

shortcuts

getShortcutMenuItem

deleteShortcut

getAccessibleContext