Options Menu

The Options Menu is opened by pressing the device MENU key. When opened, the Icon Menu is displayed, which holds the first six menu items. If more than six items are added to the Options Menu, then those that can't fit in the Icon Menu are revealed in the Expanded Menu, via the "More" menu item. The Expanded Menu is automatically added when there are more than six items.

The Options Menu is where you should include basic application functions and any necessary navigation items (e.g., to a home screen or application settings). You can also add Submenus for organizing topics and including extra menu functionality.

When this menu is opened for the first time, the Android system will call the Activity onCreateOptionsMenu() callback method. Override this method in your Activity and populate the Menu object given to you. You can populate the menu by inflating a menu resource that was defined in XML, or by calling add() for each item you'd like in the menu. This method adds a MenuItem, and returns the newly created object to you. You can use the returned MenuItem to set additional properties like an icon, a keyboard shortcut, an intent, and other settings

for the item.

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There are multiple add() methods. Usually, you'll want to use one that accepts an itemId argument. This is a unique integer that allows you to identify the item during a callback.

When a menu item is selected from the Options Menu, you will recieve a callback to the onOptionsitemSelectedn method of your Activity. This callback passes you the Menuitem that has been selected. You can identify the item by requesting the itemId, with getItemId(), which returns the integer that was assigned with the add() method. Once you identify the menu item, you can take the appropriate action.

Here's an example of this procedure, inside an Activity, wherein we create an Options Menu and handle item selections:

public boolean onCreateOptionsMenu(Menu menu) { menu.add(0, MENU_NEW_GAME, 0, "New Game"); menu.add(o, MENU_QUIT, 0, "Quit"); return true;

/* Handles item selections */

public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case MENU_NEW_GAME: newGame(); return true; case MENU_QUIT: quit(); return true;

return false;

The add() method used in this sample takes four arguments: groupId, itemId, order, and title. The groupId allows you to associate this menu item with a group of other items (more about Menu groups, below) — in this example, we ignore it. itemId is a unique integer that we give the MenuItem so that can identify it in the next callback. order allows us to define the display order of the item — by default, they are displayed by the order in which we add them. title is, of course, the name that goes on the menu item (this can also be a string resource, and we recommend you do it that way for easier localization).

Tip: If you have several menu items that can be grouped together with a title, consider organizing them into a Submenu.

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