com.google.gwt.user.client.ui
Class MenuBar

java.lang.Object
  com.google.gwt.user.client.ui.UIObject
      com.google.gwt.user.client.ui.Widget
          com.google.gwt.user.client.ui.MenuBar

All Implemented Interfaces:

EventListener, HasAnimation, PopupListener

public class MenuBar
extends Widget
implements PopupListener, HasAnimation

A standard menu bar widget. A menu bar can contain any number of menu items, each of which can either fire a Command or open a cascaded menu bar.

CSS Style Rules

• .gwt-MenuBar { the menu bar itself }
• .gwt-MenuBar-horizontal { dependent style applied to horizontal menu bars }
• .gwt-MenuBar-vertical { dependent style applied to vertical menu bars }
• .gwt-MenuBar .gwt-MenuItem { menu items }
• .gwt-MenuBar .gwt-MenuItem-selected { selected menu items }
• .gwt-MenuBar .gwt-MenuItemSeparator { section breaks between menu items }
• .gwt-MenuBar .gwt-MenuItemSeparator .menuSeparatorInner { inner component of section separators }
• .gwt-MenuBar .menuPopupTopLeft { the top left cell }
• .gwt-MenuBar .menuPopupTopLeftInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupTopCenter { the top center cell }
• .gwt-MenuBar .menuPopupTopCenterInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupTopRight { the top right cell }
• .gwt-MenuBar .menuPopupTopRightInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupMiddleLeft { the middle left cell }
• .gwt-MenuBar .menuPopupMiddleLeftInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupMiddleCenter { the middle center cell }
• .gwt-MenuBar .menuPopupMiddleCenterInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupMiddleRight { the middle right cell }
• .gwt-MenuBar .menuPopupMiddleRightInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupBottomLeft { the bottom left cell }
• .gwt-MenuBar .menuPopupBottomLeftInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupBottomCenter { the bottom center cell }
• .gwt-MenuBar .menuPopupBottomCenterInner { the inner element of the cell }
• .gwt-MenuBar .menuPopupBottomRight { the bottom right cell }
• .gwt-MenuBar .menuPopupBottomRightInner { the inner element of the cell }

Example

public class MenuBarExample implements EntryPoint {

  public void onModuleLoad() {
    // Make a command that we will execute from all leaves.
    Command cmd = new Command() {
      public void execute() {
        Window.alert("You selected a menu item!");
      }
    };

    // Make some sub-menus that we will cascade from the top menu.
    MenuBar fooMenu = new MenuBar(true);
    fooMenu.addItem("the", cmd);
    fooMenu.addItem("foo", cmd);
    fooMenu.addItem("menu", cmd);

    MenuBar barMenu = new MenuBar(true);
    barMenu.addItem("the", cmd);
    barMenu.addItem("bar", cmd);
    barMenu.addItem("menu", cmd);

    MenuBar bazMenu = new MenuBar(true);
    bazMenu.addItem("the", cmd);
    bazMenu.addItem("baz", cmd);
    bazMenu.addItem("menu", cmd);

    // Make a new menu bar, adding a few cascading menus to it.
    MenuBar menu = new MenuBar();
    menu.addItem("foo", fooMenu);
    menu.addItem("bar", barMenu);
    menu.addItem("baz", bazMenu);

    // Add it to the root panel.
    RootPanel.get().add(menu);
  }
}

Nested Class Summary

static interface

MenuBar.MenuBarImages An ImageBundle that provides images for MenuBar.

Nested classes/interfaces inherited from class com.google.gwt.user.client.ui.UIObject

UIObject.DebugIdImpl, UIObject.DebugIdImplEnabled

Field Summary

Fields inherited from class com.google.gwt.user.client.ui.UIObject

DEBUG_ID_PREFIX

Constructor Summary

MenuBar()
Creates an empty horizontal menu bar.

MenuBar(boolean vertical)
Creates an empty menu bar.

MenuBar(boolean vertical, MenuBar.MenuBarImages images)
Creates an empty menu bar that uses the specified image bundle for menu images.

MenuBar(MenuBar.MenuBarImages images)
Creates an empty horizontal menu bar that uses the specified image bundle for menu images.

Method Summary

MenuItem	addItem(MenuItem item) Adds a menu item to the bar.
MenuItem	addItem(java.lang.String text, boolean asHTML, Command cmd) Adds a menu item to the bar, that will fire the given command when it is selected.
MenuItem	addItem(java.lang.String text, boolean asHTML, MenuBar popup) Adds a menu item to the bar, that will open the specified menu when it is selected.
MenuItem	addItem(java.lang.String text, Command cmd) Adds a menu item to the bar, that will fire the given command when it is selected.
MenuItem	addItem(java.lang.String text, MenuBar popup) Adds a menu item to the bar, that will open the specified menu when it is selected.
MenuItemSeparator	addSeparator() Adds a thin line to the MenuBar to separate sections of MenuItems.
MenuItemSeparator	addSeparator(MenuItemSeparator separator) Adds a thin line to the MenuBar to separate sections of MenuItems.
void	clearItems() Removes all menu items from this menu bar.
boolean	getAutoOpen() Gets whether this menu bar's child menus will open when the mouse is moved over it.
protected java.util.List<MenuItem>	getItems() Returns a list containing the MenuItem objects in the menu bar.
protected MenuItem	getSelectedItem() Returns the MenuItem that is currently selected (highlighted) by the user.
boolean	isAnimationEnabled()
void	onBrowserEvent(Event event) Fired whenever a browser event is received.
protected void	onDetach() This method is called when a widget is detached from the browser's document.
protected void	onEnsureDebugId(java.lang.String baseID) Affected Elements: -item# = the MenuItem at the specified index.
void	onPopupClosed(PopupPanel sender, boolean autoClosed) Fired when the popup is closed.
void	removeItem(MenuItem item) Removes the specified menu item from the bar.
void	removeSeparator(MenuItemSeparator separator) Removes the specified MenuItemSeparator from the bar.
void	setAnimationEnabled(boolean enable) Enable or disable animations.
void	setAutoOpen(boolean autoOpen) Sets whether this menu bar's child menus will open when the mouse is moved over it.

Methods inherited from class com.google.gwt.user.client.ui.Widget

doAttachChildren, doDetachChildren, getParent, isAttached, onAttach, onLoad, onUnload, removeFromParent

Methods inherited from class com.google.gwt.user.client.ui.UIObject

addStyleDependentName, addStyleName, ensureDebugId, ensureDebugId, ensureDebugId, getAbsoluteLeft, getAbsoluteTop, getElement, getOffsetHeight, getOffsetWidth, getStyleElement, getStyleName, getStyleName, getStylePrimaryName, getStylePrimaryName, getTitle, isVisible, isVisible, removeStyleDependentName, removeStyleName, setElement, setElement, setHeight, setPixelSize, setSize, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setTitle, setVisible, setVisible, setWidth, sinkEvents, toString, unsinkEvents

Methods inherited from class java.lang.Object

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

Constructor Detail

MenuBar

public MenuBar()

Creates an empty horizontal menu bar.

MenuBar

public MenuBar(MenuBar.MenuBarImages images)

Creates an empty horizontal menu bar that uses the specified image bundle for menu images.

Parameters:

images - a bundle that provides images for this menu

MenuBar

public MenuBar(boolean vertical)

Creates an empty menu bar.

Parameters:

vertical - true to orient the menu bar vertically

MenuBar

public MenuBar(boolean vertical,
               MenuBar.MenuBarImages images)

Creates an empty menu bar that uses the specified image bundle for menu images.

Parameters:

vertical - true to orient the menu bar vertically

images - a bundle that provides images for this menu

Method Detail

addItem

public MenuItem addItem(MenuItem item)

Adds a menu item to the bar.

Parameters:

item - the item to be added

Returns:

the MenuItem object

addItem

public MenuItem addItem(java.lang.String text,
                        boolean asHTML,
                        Command cmd)

Adds a menu item to the bar, that will fire the given command when it is selected.

Parameters:

text - the item's text

asHTML - true to treat the specified text as html

cmd - the command to be fired

Returns:

the MenuItem object created

addItem

public MenuItem addItem(java.lang.String text,
                        boolean asHTML,
                        MenuBar popup)

Adds a menu item to the bar, that will open the specified menu when it is selected.

Parameters:

text - the item's text

asHTML - true to treat the specified text as html

popup - the menu to be cascaded from it

Returns:

the MenuItem object created

addItem

public MenuItem addItem(java.lang.String text,
                        Command cmd)

Adds a menu item to the bar, that will fire the given command when it is selected.

Parameters:

text - the item's text

cmd - the command to be fired

Returns:

the MenuItem object created

addItem

public MenuItem addItem(java.lang.String text,
                        MenuBar popup)

Adds a menu item to the bar, that will open the specified menu when it is selected.

Parameters:

text - the item's text

popup - the menu to be cascaded from it

Returns:

the MenuItem object created

addSeparator

public MenuItemSeparator addSeparator()

Adds a thin line to the MenuBar to separate sections of MenuItems.

Returns:

the MenuItemSeparator object created

addSeparator

public MenuItemSeparator addSeparator(MenuItemSeparator separator)

Adds a thin line to the MenuBar to separate sections of MenuItems.

Parameters:

separator - the MenuItemSeparator to be added

Returns:

the MenuItemSeparator object

clearItems

public void clearItems()

Removes all menu items from this menu bar.

getAutoOpen

public boolean getAutoOpen()

Gets whether this menu bar's child menus will open when the mouse is moved over it.

Returns:

true if child menus will auto-open

isAnimationEnabled

public boolean isAnimationEnabled()

Specified by:

isAnimationEnabled in interface HasAnimation

Returns:

true if animations are enabled, false if not

onBrowserEvent

public void onBrowserEvent(Event event)

Description copied from interface: EventListener

Fired whenever a browser event is received.

Specified by:

onBrowserEvent in interface EventListener

Overrides:

onBrowserEvent in class Widget

Parameters:

event - the event received

onPopupClosed

public void onPopupClosed(PopupPanel sender,
                          boolean autoClosed)

Description copied from interface: PopupListener

Fired when the popup is closed.

Specified by:

onPopupClosed in interface PopupListener

Parameters:

sender - popup being closed.

autoClosed - true if the popup was automatically closed; false if it was closed programmatically.

removeItem

public void removeItem(MenuItem item)

Removes the specified menu item from the bar.

Parameters:

item - the item to be removed

removeSeparator

public void removeSeparator(MenuItemSeparator separator)

Removes the specified MenuItemSeparator from the bar.

Parameters:

separator - the separator to be removed

setAnimationEnabled

public void setAnimationEnabled(boolean enable)

Description copied from interface: HasAnimation

Enable or disable animations.

Specified by:

setAnimationEnabled in interface HasAnimation

Parameters:

enable - true to enable, false to disable

setAutoOpen

public void setAutoOpen(boolean autoOpen)

Sets whether this menu bar's child menus will open when the mouse is moved over it.

Parameters:

autoOpen - true to cause child menus to auto-open

getItems

protected java.util.List<MenuItem> getItems()

Returns a list containing the MenuItem objects in the menu bar. If there are no items in the menu bar, then an empty List object will be returned.

Returns:

a list containing the MenuItem objects in the menu bar

getSelectedItem

protected MenuItem getSelectedItem()

Returns the MenuItem that is currently selected (highlighted) by the user. If none of the items in the menu are currently selected, then null will be returned.

Returns:

the MenuItem that is currently selected, or null if no items are currently selected

onDetach

protected void onDetach()

Description copied from class: Widget

This method is called when a widget is detached from the browser's document. To receive notification before a Widget is removed from the document, override the Widget.onUnload() method.

Subclasses that override this method must call super.onDetach() to ensure that the Widget has been detached from the underlying Element. Failure to do so will result in application memory leaks due to circular references between DOM Elements and JavaScript objects.

Overrides:

onDetach in class Widget

onEnsureDebugId

protected void onEnsureDebugId(java.lang.String baseID)

Affected Elements:

• -item# = the MenuItem at the specified index.

Overrides:

onEnsureDebugId in class UIObject

Parameters:

baseID - the base ID used by the main element

See Also:

UIObject.onEnsureDebugId(String)