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
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
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 |
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 classMenuComponent
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 interfaceMenuContainer
- 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()
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 interfaceAccessible
- Overrides:
-
getAccessibleContext
in classMenuComponent
- Returns:
- an AccessibleAWTMenuBar that serves as the AccessibleContext of this MenuBar
- Since:
- 1.3