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author | Scott Main <smain@google.com> | 2012-02-01 11:51:53 -0800 |
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committer | Android Git Automerger <android-git-automerger@android.com> | 2012-02-01 11:51:53 -0800 |
commit | 0f4dc8f7d762f3ceab91e7b3a24bcb88989c7190 (patch) | |
tree | d79ad0e957ab6a9ed37e3e46f75257d4816cd05f /docs | |
parent | d528f036d1185efff49e0a576084e711d2f550d8 (diff) | |
parent | 414cc6cfcdb6d766d095f0af1da76e7da946af84 (diff) | |
download | frameworks_base-0f4dc8f7d762f3ceab91e7b3a24bcb88989c7190.zip frameworks_base-0f4dc8f7d762f3ceab91e7b3a24bcb88989c7190.tar.gz frameworks_base-0f4dc8f7d762f3ceab91e7b3a24bcb88989c7190.tar.bz2 |
am 414cc6cf: am 9af875ec: am 5e095939: docs: update menu guide with CAB and popup menu, plus many other revisions
* commit '414cc6cfcdb6d766d095f0af1da76e7da946af84':
docs: update menu guide with CAB and popup menu, plus many other revisions
Diffstat (limited to 'docs')
-rw-r--r-- | docs/html/guide/guide_toc.cs | 2 | ||||
-rw-r--r-- | docs/html/guide/topics/ui/actionbar.jd | 14 | ||||
-rw-r--r-- | docs/html/guide/topics/ui/menus.jd | 1008 | ||||
-rw-r--r-- | docs/html/images/ui/menu-context.png | bin | 0 -> 45304 bytes | |||
-rw-r--r-- | docs/html/images/ui/popupmenu.png | bin | 0 -> 8186 bytes |
5 files changed, 690 insertions, 334 deletions
diff --git a/docs/html/guide/guide_toc.cs b/docs/html/guide/guide_toc.cs index 6c01d44..4a9a684 100644 --- a/docs/html/guide/guide_toc.cs +++ b/docs/html/guide/guide_toc.cs @@ -131,7 +131,7 @@ </a></li> <li><a href="<?cs var:toroot ?>guide/topics/ui/menus.html"> <span class="en">Menus</span> - </a></li> + </a> <span class="new">updated</span></li> <li><a href="<?cs var:toroot ?>guide/topics/ui/actionbar.html"> <span class="en">Action Bar</span> </a></li> diff --git a/docs/html/guide/topics/ui/actionbar.jd b/docs/html/guide/topics/ui/actionbar.jd index b83bde7..b35bc5f 100644 --- a/docs/html/guide/topics/ui/actionbar.jd +++ b/docs/html/guide/topics/ui/actionbar.jd @@ -113,9 +113,10 @@ accessible to the user in a predictable way. href="{@docRoot}guide/topics/ui/menus.html#OptionsMenu">options menu</a> directly in the action bar, as "action items." Action items can also provide an "action view," which provides an embedded widget for even more immediate action behaviors. Menu items that are not promoted -to an action item are available in the overflow menu, revealed by either the device MENU button +to an action item are available in the overflow menu, revealed by either the device <em>Menu</em> +button (when available) or by an "overflow menu" button in the action bar (when the device does not -include a MENU button).</p> +include a <em>Menu</em> button).</p> </li> </ul> @@ -125,6 +126,10 @@ href="{@docRoot}resources/samples/HoneycombGallery/index.html">Honeycomb Gallery landscape handset), showing the logo on the left, navigation tabs, and an action item on the right (plus the overflow menu button).</p> +<p class="note"><strong>Note:</strong> If you're looking for information about the contextual +action bar for displaying contextual action items, see the <a +href="{@docRoot}guide/topics/ui/menus.html#context-menu">Menu</a> guide.</p> + <div class="design-announce"> <p><strong>Action Bar Design</strong></p> @@ -225,9 +230,10 @@ later—calling {@link android.app.Activity#getActionBar()} will return null href="{@docRoot}guide/topics/ui/menus.html#OptionsMenu">options menu</a>. To do this, you can declare that the menu item should appear in the action bar as an "action item." An action item can include an icon and/or a text title. If a menu item does not appear as an action item, then the -system places it in the overflow menu. The overflow menu is revealed either by the device MENU +system places it in the overflow menu. The overflow menu is revealed either by the device +<em>Menu</em> button (if provided by the device) or an additional button in the action bar (if the device does not -provide the MENU button).</p> +provide the <em>Menu</em> button).</p> <div class="figure" style="width:359px"> <img src="{@docRoot}images/ui/actionbar-item-withtext.png" height="57" alt="" /> diff --git a/docs/html/guide/topics/ui/menus.jd b/docs/html/guide/topics/ui/menus.jd index 7b5b3dc..a2313b3 100644 --- a/docs/html/guide/topics/ui/menus.jd +++ b/docs/html/guide/topics/ui/menus.jd @@ -6,77 +6,129 @@ parent.link=index.html <div id="qv-wrapper"> <div id="qv"> <h2>In this document</h2> - <ol> - <li><a href="#xml">Creating a Menu Resource</a></li> - <li><a href="#Inflating">Inflating a Menu Resource</a> - <li><a href="#options-menu">Creating an Options Menu</a> - <ol> - <li><a href="#ChangingTheMenu">Changing menu items at runtime</a></li> - </ol> - </li> - <li><a href="#context-menu">Creating a Context Menu</a></li> - <li><a href="#submenu">Creating a Submenu</a></li> - <li><a href="#features">Other Menu Features</a> - <ol> - <li><a href="#groups">Menu groups</a></li> - <li><a href="#checkable">Checkable menu items</a></li> - <li><a href="#shortcuts">Shortcut keys</a></li> - <li><a href="#intents">Dynamically adding menu intents</a></li> - </ol> - </li> - </ol> +<ol> + <li><a href="#xml">Defining a Menu in XML</a></li> + <li><a href="#options-menu">Creating an Options Menu</a> + <ol> + <li><a href="#RespondingOptionsMenu">Handling click events</a></li> + <li><a href="#ChangingTheMenu">Changing menu items at runtime</a></li> + </ol> + </li> + <li><a href="#context-menu">Creating Contextual Menus</a> + <ol> + <li><a href="#FloatingContextMenu">Creating a floating context menu</a></li> + <li><a href="#CAB">Using the contextual action bar</a></li> + </ol> + </li> + <li><a href="#PopupMenu">Creating a Popup Menu</a> + <ol> + <li><a href="#PopupEvents">Handling click events</a></li> + </ol> + </li> + <li><a href="#groups">Creating Menu Groups</a> + <ol> + <li><a href="#checkable">Using checkable menu items</a></li> + </ol> + </li> + <li><a href="#intents">Adding Menu Items Based on an Intent</a> + <ol> + <li><a href="#AllowingToAdd">Allowing your activity to be added to other menus</a></li> + </ol> + </li> +</ol> <h2>Key classes</h2> <ol> <li>{@link android.view.Menu}</li> <li>{@link android.view.MenuItem}</li> <li>{@link android.view.ContextMenu}</li> - <li>{@link android.view.SubMenu}</li> + <li>{@link android.view.ActionMode}</li> </ol> <h2>See also</h2> <ol> <li><a href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a></li> <li><a href="{@docRoot}guide/topics/resources/menu-resource.html">Menu Resource</a></li> + <li><a +href="http://android-developers.blogspot.com/2012/01/say-goodbye-to-menu-button.html">Say +Goodbye to the Menu Button</a></li> </ol> </div> </div> -<p>Menus are an important part of an activity's user interface, which provide users a familiar -way to perform actions. Android offers a simple framework for you to add standard -menus to your application.</p> +<p>Menus are a common user interface component in many types of applications. To provide a familiar +and consistent user experience, you should use the {@link android.view.Menu} APIs to present user +actions and other options in your activities.</p> + +<p>Beginning with Android 3.0 (API level 11), Android-powered devices are no longer required to +provide a dedicated <em>Menu</em> button. With this change, Android apps should migrate away from a +dependence on the traditional 6-item menu panel and instead provide an action bar to present common +user actions.</p> + +<p>Although the design and user experience for some menu items have changed, the semantics to define +a set of actions and options is still based on the {@link android.view.Menu} APIs. This +guide shows how to create the three fundamental types of menus or action presentations on all +versions of Android:</p> -<p>There are three types of application menus:</p> <dl> - <dt><strong>Options Menu</strong></dt> - <dd>The primary collection of menu items for an activity, which appears when the user touches -the MENU button. When your application is running on Android 3.0 or later, you can provide -quick access to select menu items by placing them directly in the <a -href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a>, as "action items."</dd> - <dt><strong>Context Menu</strong></dt> - <dd>A floating list of menu items that appears when the user touches and holds a view -that's registered to provide a context menu. + <dt><strong>Options menu and action bar</strong></dt> + <dd>The <a href="#options-menu">options menu</a> is the primary collection of menu items for an +activity. It's where you should place actions that have a global impact on the app, such as +"Search," "Compose email," and "Settings." + <p>If you're developing for Android 2.3 or lower, users can +reveal the options menu panel by pressing the <em>Menu</em> button.</p> + <p>On Android 3.0 and higher, items from the options menu are presented by the <a +href="{@docRoot}guide/topics/ui/actionbar.html">action bar</a> as a combination of on-screen action +items and overflow options. Beginning with Android 3.0, the <em>Menu</em> button is deprecated (some +devices +don't have one), so you should migrate toward using the action bar to provide access to actions and +other options.</p> + <p>See the section about <a href="#options-menu">Creating an Options Menu</a>.</p> + </dd> + + <dt><strong>Context menu and contextual action mode</strong></dt> + + <dd>A context menu is a <a href="#FloatingContextMenu">floating menu</a> that appears when the +user performs a long-click on an element. It provides actions that affect the selected content or +context frame. + <p>When developing for Android 3.0 and higher, you should instead use the <a +href="#CAB">contextual action mode</a> to enable actions on selected content. This mode displays +action items that affect the selected content in a bar at the top of the screen and allows the user +to select multiple items.</p> + <p>See the section about <a href="#context-menu">Creating Contextual Menus</a>.</p> +</dd> + + <dt><strong>Popup menu</strong></dt> + <dd>A popup menu displays a list of items in a vertical list that's anchored to the view that +invoked the menu. It's good for providing an overflow of actions that relate to specific content or +to provide options for a second part of a command. Actions in a popup menu should +<strong>not</strong> directly affect the corresponding content—that's what contextual actions +are for. Rather, the popup menu is for extended actions that relate to regions of content in your +activity. + <p>See the section about <a href="#PopupMenu">Creating a Popup Menu</a>.</p> </dd> - <dt><strong>Submenu</strong></dt> - <dd>A floating list of menu items that appears when the user touches a menu item that contains -a nested menu.</dd> </dl> -<p>This document shows you how to create each type of menu, using XML to define the content of -the menu and callback methods in your activity to respond when the user selects an item.</p> +<h2 id="xml">Defining a Menu in XML</h2> -<h2 id="xml">Creating a Menu Resource</h2> +<p>For all menu types, Android provides a standard XML format to define menu items. +Instead of building a menu in your activity's code, you should define a menu and all its items in an +XML <a href="{@docRoot}guide/topics/resources/menu-resource.html">menu resource</a>. You can then +inflate the menu resource (load it as a {@link android.view.Menu} object) in your activity or +fragment.</p> -<p>Instead of instantiating a {@link android.view.Menu} in your application code, you should -define a menu and all its items in an XML <a -href="{@docRoot}guide/topics/resources/menu-resource.html">menu resource</a>, then inflate the menu -resource (load it as a programmable object) in your application code. Using a menu resource to -define your menu is a good practice because it separates the content for the menu from your -application code. It's also easier to visualize the structure and content of a menu in XML.</p> +<p>Using a menu resource is a good practice for a few reasons:</p> +<ul> + <li>It's easier to visualize the menu structure in XML.</li> + <li>It separates the content for the menu from your application's behavioral code.</li> + <li>It allows you to create alternative menu configurations for different platform versions, +screen sizes, and other configurations by leveraging the <a +href="{@docRoot}guide/topics/resources/index.html">app resources</a> framework.</li> +</ul> -<p>To create a menu resource, create an XML file inside your project's <code>res/menu/</code> +<p>To define the menu, create an XML file inside your project's <code>res/menu/</code> directory and build the menu with the following elements:</p> <dl> <dt><code><menu></code></dt> @@ -90,8 +142,8 @@ element may contain a nested <code><menu></code> element in order to create a <dt><code><group></code></dt> <dd>An optional, invisible container for {@code <item>} elements. It allows you to -categorize menu items so they share properties such as active state and visibility. See the -section about <a href="#groups">Menu groups</a>.</dd> +categorize menu items so they share properties such as active state and visibility. For more +information, see the section about <a href="#groups">Creating Menu Groups</a>.</dd> </dl> @@ -101,14 +153,17 @@ section about <a href="#groups">Menu groups</a>.</dd> <menu xmlns:android="http://schemas.android.com/apk/res/android"> <item android:id="@+id/new_game" android:icon="@drawable/ic_new_game" - android:title="@string/new_game" /> + android:title="@string/new_game" + android:showAsAction="ifRoom"/> <item android:id="@+id/help" android:icon="@drawable/ic_help" android:title="@string/help" /> </menu> </pre> -<p>This example defines a menu with two items. Each item includes the attributes:</p> +<p>The <code><item></code> element supports several attributes you can use to define an item's +appearance and behavior. The items in the above menu include the following attributes:</p> + <dl> <dt>{@code android:id}</dt> <dd>A resource ID that's unique to the item, which allows the application can recognize the item @@ -117,158 +172,175 @@ when the user selects it.</dd> <dd>A reference to a drawable to use as the item's icon.</dd> <dt>{@code android:title}</dt> <dd>A reference to a string to use as the item's title.</dd> + <dt>{@code android:showAsAction}</dt> + <dd>Specifies when and how this item should appear as an action item in the <a +href="{@docRoot}guide/topics/ui/actionbar.html">action bar</a>.</dd> </dl> -<p>There are many more attributes you can include in an {@code <item>}, including some that - specify how the item may appear in the <a -href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a>. For more information about the XML -syntax and attributes for a menu resource, see the <a -href="{@docRoot}guide/topics/resources/menu-resource.html">Menu Resource</a> reference.</p> +<p>These are the most important attributes you should use, but there are many more available. +For information about all the supported attributes, see the <a +href="{@docRoot}guide/topics/resources/menu-resource.html">Menu Resource</a> document.</p> - - -<h2 id="Inflating">Inflating a Menu Resource</h2> - -<p>From your application code, you can inflate a menu resource (convert the XML resource into a -programmable object) using -{@link android.view.MenuInflater#inflate(int,Menu) MenuInflater.inflate()}. For -example, the following code inflates the <code>game_menu.xml</code> file defined above, during the -{@link android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} callback method, to -use the menu as the activity's Options Menu:</p> +<p>You can add a submenu to an item in any menu (except a submenu) by adding a {@code <menu>} +element as the child of an {@code <item>}. Submenus are useful when your application has a lot +of functions that can be organized into topics, like items in a PC application's menu bar (File, +Edit, View, etc.). For example:</p> <pre> -@Override -public boolean onCreateOptionsMenu(Menu menu) { - MenuInflater inflater = getMenuInflater(); - inflater.inflate(R.menu.game_menu, menu); - return true; -} +<?xml version="1.0" encoding="utf-8"?> +<menu xmlns:android="http://schemas.android.com/apk/res/android"> + <item android:id="@+id/file" + android:title="@string/file" > + <!-- "file" submenu --> + <menu> + <item android:id="@+id/create_new" + android:title="@string/create_new" /> + <item android:id="@+id/open" + android:title="@string/open" /> + </menu> + </item> +</menu> </pre> -<p>The {@link android.app.Activity#getMenuInflater()} method returns a {@link -android.view.MenuInflater} for the activity. With this object, you can call {@link -android.view.MenuInflater#inflate(int,Menu) inflate()}, which inflates a menu resource into a -{@link android.view.Menu} object. In this example, the menu resource defined by -<code>game_menu.xml</code> -is inflated into the {@link android.view.Menu} that was passed into {@link -android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()}. (This callback method for -the Options Menu is discussed more in the next section.)</p> +<p>To use the menu in your activity, you need to inflate the menu resource (convert the XML +resource into a programmable object) using {@link android.view.MenuInflater#inflate(int,Menu) +MenuInflater.inflate()}. In the following sections, you'll see how to inflate a menu for each +menu type.</p> <h2 id="options-menu">Creating an Options Menu</h2> -<div class="figure" style="width:200px"> +<div class="figure" style="width:200px;margin:0"> <img src="{@docRoot}images/options_menu.png" height="333" alt="" /> - <p class="img-caption"><strong>Figure 1.</strong> Screenshot of the Options Menu in the -Browser.</p> + <p class="img-caption"><strong>Figure 1.</strong> Options menu in the +Browser, on Android 2.3.</p> </div> -<p>The Options Menu is where you should include basic activity actions and necessary navigation -items (for example, a button to open the application settings). Items in the Options Menu are -accessible in two distinct ways: the MENU button or in the <a -href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a> (on devices running Android 3.0 -or higher).</p> - -<p>When running on a device with Android 2.3 and lower, the Options Menu appears at the bottom of -the screen, as shown in figure 1. When opened, the first visible portion of the Options Menu is -the icon menu. It holds the first six menu items. If you add more than six items to the -Options Menu, Android places the sixth item and those after it into the overflow menu, which the -user can open by touching the "More" menu item.</p> - -<p>On Android 3.0 and higher, items from the Options Menu is placed in the Action Bar, which appears -at the top of the activity in place of the traditional title bar. By default all items from the -Options Menu are placed in the overflow menu, which the user can open by touching the menu icon -on the right side of the Action Bar. However, you can place select menu items directly in the -Action Bar as "action items," for instant access, as shown in figure 2.</p> - -<p>When the Android system creates the Options Menu for the first time, it calls your -activity's {@link android.app.Activity#onCreateOptionsMenu(Menu) -onCreateOptionsMenu()} method. Override this method in your activity -and populate the {@link android.view.Menu} that is passed into the method, -{@link android.view.Menu} by inflating a menu resource as described above in <a -href="#Inflating">Inflating a Menu Resource</a>. For example:</p> +<p>The options menu is where you should include actions and other options that are relevant to the +current activity context, such as "Search," "Compose email," and "Settings."</p> + +<p>Where the items in your options menu appear on the screen depends on the version for which you've +developed your application:</p> + +<ul> + <li>If you've developed your application for <strong>Android 2.3.x (API level 10) or +lower</strong>, the contents of your options menu appear at the bottom of the screen when the user +presses the <em>Menu</em> button, as shown in figure 1. When opened, the first visible portion is +the icon +menu, which holds up to six menu items. If your menu includes more than six items, Android places +the sixth item and the rest into the overflow menu, which the user can open by selecting +<em>More</em>.</li> + + <li>If you've developed your application for <strong>Android 3.0 (API level 11) and +higher</strong>, items from the options menu are available in the <a +href="{@docRoot}guide/topics/ui/actionbar.html">action bar</a>. By default, the system +places all items in the action overflow, which the user can reveal with the action overflow icon on +the right side of the action bar (or by pressing the device <em>Menu</em> button, if available). To +enable +quick access to important actions, you can promote a few items to appear in the action bar by adding +{@code android:showAsAction="ifRoom"} to the corresponding {@code <item>} elements (see figure +2). <p>For more information about action items and other action bar behaviors, see the <a +href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a> guide. </p> +<p class="note"><strong>Note:</strong> Even if you're <em>not</em> developing for Android 3.0 or +higher, you can build your own action bar layout for a similar effect. For an example of how you can +support older versions of Android with an action bar, see the <a +href="{@docRoot}resources/samples/ActionBarCompat/index.html">Action Bar Compatibility</a> +sample.</p> +</li> +</ul> + +<img src="{@docRoot}images/ui/actionbar.png" alt="" /> +<p class="img-caption"><strong>Figure 2.</strong> Action bar from the <a +href="{@docRoot}resources/samples/HoneycombGallery/index.html">Honeycomb Gallery</a> app, showing +navigation tabs and a camera action item (plus the action overflow button).</p> + +<p>You can declare items for the options menu from either your {@link android.app.Activity} +subclass or a {@link android.app.Fragment} subclass. If both your activity and fragment(s) +declare items for the options menu, they are combined in the UI. The activity's items appear +first, followed by those of each fragment in the order in which each fragment is added to the +activity. If necessary, you can re-order the menu items with the {@code android:orderInCategory} +attribute in each {@code <item>} you need to move.</p> + +<p>To specify the options menu for an activity, override {@link +android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} (fragments provide their +own {@link android.app.Fragment#onCreateOptionsMenu onCreateOptionsMenu()} callback). In this +method, you can inflate your menu resource (<a href="#xml">defined in XML</a>) into the {@link +android.view.Menu} provided in the callback. For example:</p> <pre> @Override public boolean onCreateOptionsMenu(Menu menu) { - MenuInflater inflater = getMenuInflater(); + MenuInflater inflater = {@link android.app.Activity#getMenuInflater()}; inflater.inflate(R.menu.game_menu, menu); return true; } </pre> -<div class="figure" style="width:450px"> -<img src="{@docRoot}images/ui/actionbar.png" alt="" /> -<p class="img-caption"><strong>Figure 2.</strong> Action bar from the <a -href="{@docRoot}resources/samples/HoneycombGallery/index.html">Honeycomb Gallery</a> app, including -navigation tabs and a camera action item (plus the overflow menu button).</p> -</div> +<p>You can also add menu items using {@link android.view.Menu#add(int,int,int,int) +add()} and retrieve items with {@link android.view.Menu#findItem findItem()} to revise their +properties with {@link android.view.MenuItem} APIs.</p> -<p>You can also populate the menu in code, using {@link android.view.Menu#add(int,int,int,int) -add()} to add items to the {@link android.view.Menu}.</p> +<p>If you've developed your application for Android 2.3.x and lower, the system calls {@link +android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} to create the options menu +when the user opens the menu for the first time. If you've developed for Android 3.0 and higher, the +system calls {@link android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} when +starting the activity, in order to show items to the action bar.</p> -<p class="note"><strong>Note:</strong> On Android 2.3 and lower, the system calls {@link -android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} to create the Options Menu -when the user opens it for the first time, but on Android 3.0 and greater, the system creates it as -soon as the activity is created, in order to populate the Action Bar.</p> -<h3 id="RespondingOptionsMenu">Responding to user action</h3> +<h3 id="RespondingOptionsMenu">Handling click events</h3> -<p>When the user selects a menu item from the Options Menu (including action items in the -Action Bar), the system calls your activity's -{@link android.app.Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected()} -method. This method passes the -{@link android.view.MenuItem} that the user selected. You can identify the menu item by calling -{@link android.view.MenuItem#getItemId()}, which returns the unique ID for the menu -item (defined by the {@code android:id} attribute in the menu resource or with an integer -given to the {@link android.view.Menu#add(int,int,int,int) add()} method). You can match this ID -against known menu items and perform the appropriate action. For example:</p> +<p>When the user selects an item from the options menu (including action items in the action bar), +the system calls your activity's {@link android.app.Activity#onOptionsItemSelected(MenuItem) +onOptionsItemSelected()} method. This method passes the {@link android.view.MenuItem} selected. You +can identify the item by calling {@link android.view.MenuItem#getItemId()}, which returns the unique +ID for the menu item (defined by the {@code android:id} attribute in the menu resource or with an +integer given to the {@link android.view.Menu#add(int,int,int,int) add()} method). You can match +this ID against known menu items to perform the appropriate action. For example:</p> <pre> @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle item selection switch (item.getItemId()) { - case R.id.new_game: - newGame(); - return true; - case R.id.help: - showHelp(); - return true; - default: - return super.onOptionsItemSelected(item); + case R.id.new_game: + newGame(); + return true; + case R.id.help: + showHelp(); + return true; + default: + return super.onOptionsItemSelected(item); } } </pre> -<p>In this example, {@link android.view.MenuItem#getItemId()} queries the ID for the selected menu -item and the switch statement compares the ID against the resource IDs that were assigned to menu -items in the XML resource. When a switch case successfully handles the menu item, it -returns {@code true} to indicate that the item selection was handled. Otherwise, the default -statement passes the menu item to the super class, in -case it can handle the item selected. (If you've directly extended the {@link android.app.Activity} -class, then the super class returns {@code false}, but it's a good practice to -pass unhandled menu items to the super class instead of directly returning {@code false}.)</p> - -<p>Additionally, Android 3.0 adds the ability for you to define the on-click behavior for a menu -item in the <a href="{@docRoot}guide/topics/resources/menu-resource.html">menu resource</a> XML, -using the {@code android:onClick} attribute. So you don't need to implement {@link -android.app.Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected()}. Using the {@code -android:onClick} attribute, you can specify a method to call when the user selects the menu item. -Your activity must then implement the method specified in the {@code android:onClick} attribute so -that it accepts a single {@link android.view.MenuItem} parameter—when the system calls this -method, it passes the menu item selected.</p> +<p>When you successfully handle a menu item, return {@code true}. If you don't handle the menu +item, you should call the superclass implementation of {@link +android.app.Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected()} (the default +implementation returns false).</p> + +<p>If your activity includes fragments, the system first calls {@link +android.app.Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected()} for the activity then +for each fragment (in the order each fragment was added) until one returns +{@code true} or all fragments have been called.</p> + +<p class="note"><strong>Tip:</strong> Android 3.0 adds the ability for you to define the on-click +behavior for a menu item in XML, using the {@code android:onClick} attribute. The value for the +attribute must be the name of a method defined by the activity using the menu. The method +must be public and accept a single {@link android.view.MenuItem} parameter—when the system +calls this method, it passes the menu item selected. For more information and an example, see the <a +href="{@docRoot}guide/topics/resources/menu-resource.html">Menu Resource</a> document.</p> <p class="note"><strong>Tip:</strong> If your application contains multiple activities and -some of them provide the same Options Menu, consider creating +some of them provide the same options menu, consider creating an activity that implements nothing except the {@link android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} and {@link android.app.Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected()} methods. Then extend this class for each activity that should share the -same Options Menu. This way, you have to manage only one set of code for handling menu -actions and each descendant class inherits the menu behaviors.<br/><br/> -If you want to add menu items to one of your descendant activities, +same options menu. This way, you can manage one set of code for handling menu +actions and each descendant class inherits the menu behaviors. +If you want to add menu items to one of the descendant activities, override {@link android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} in that activity. Call {@code super.onCreateOptionsMenu(menu)} so the original menu items are created, then add new menu items with {@link @@ -278,180 +350,477 @@ behavior for individual menu items.</p> <h3 id="ChangingTheMenu">Changing menu items at runtime</h3> -<p>Once the activity is created, the {@link android.app.Activity#onCreateOptionsMenu(Menu) -onCreateOptionsMenu()} method is -called only once, as described above. The system keeps and re-uses the {@link -android.view.Menu} you define in this method until your activity is destroyed. If you want to change -the Options Menu any time after it's first created, you must override the -{@link android.app.Activity#onPrepareOptionsMenu(Menu) onPrepareOptionsMenu()} method. This passes -you the {@link android.view.Menu} object as it currently exists. This is useful if you'd like to -remove, add, disable, or enable menu items depending on the current state of your application.</p> - -<p>On Android 2.3 and lower, the system calls {@link android.app.Activity#onPrepareOptionsMenu(Menu) -onPrepareOptionsMenu()} each time the user opens the Options Menu.</p> +<p>After the system calls {@link android.app.Activity#onCreateOptionsMenu(Menu) +onCreateOptionsMenu()}, it retains an instance of the {@link android.view.Menu} you populate and +will not call {@link android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} +again unless the menu is invalidated for some reason. However, you should use {@link +android.app.Activity#onCreateOptionsMenu(Menu) onCreateOptionsMenu()} only to create the initial +menu state and not to make changes during the activity lifecycle.</p> + +<p>If you want to modify the options menu based on +events that occur during the activity lifecycle, you can do so in +the {@link android.app.Activity#onPrepareOptionsMenu(Menu) onPrepareOptionsMenu()} method. This +method passes you the {@link android.view.Menu} object as it currently exists so you can modify it, +such as add, remove, or disable items. (Fragments also provide an {@link +android.app.Fragment#onPrepareOptionsMenu onPrepareOptionsMenu()} callback.)</p> + +<p>On Android 2.3.x and lower, the system calls {@link +android.app.Activity#onPrepareOptionsMenu(Menu) +onPrepareOptionsMenu()} each time the user opens the options menu (presses the <em>Menu</em> +button).</p> -<p>On Android 3.0 and higher, you must call {@link android.app.Activity#invalidateOptionsMenu -invalidateOptionsMenu()} when you want to update the menu, because the menu is always open. The -system will then call {@link android.app.Activity#onPrepareOptionsMenu(Menu) onPrepareOptionsMenu()} -so you can update the menu items.</p> +<p>On Android 3.0 and higher, the options menu is considered to always be open when menu items are +presented in the action bar. When an event occurs and you want to perform a menu update, you must +call {@link android.app.Activity#invalidateOptionsMenu invalidateOptionsMenu()} to request that the +system call {@link android.app.Activity#onPrepareOptionsMenu(Menu) onPrepareOptionsMenu()}.</p> <p class="note"><strong>Note:</strong> -You should never change items in the Options Menu based on the {@link android.view.View} currently +You should never change items in the options menu based on the {@link android.view.View} currently in focus. When in touch mode (when the user is not using a trackball or d-pad), views cannot take focus, so you should never use focus as the basis for modifying -items in the Options Menu. If you want to provide menu items that are context-sensitive to a {@link +items in the options menu. If you want to provide menu items that are context-sensitive to a {@link android.view.View}, use a <a href="#context-menu">Context Menu</a>.</p> -<p>If you're developing for Android 3.0 or higher, be sure to also read the <a -href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a> developer guide.</p> +<h2 id="context-menu">Creating Contextual Menus</h2> -<h2 id="context-menu">Creating a Context Menu</h2> +<div class="figure" style="width:420px;margin-top:-1em"> + <img src="{@docRoot}images/ui/menu-context.png" alt="" /> + <p class="img-caption"><strong>Figure 3.</strong> Screenshots of a floating context menu (left) +and the contextual action bar (right).</p> +</div> -<p>A context menu is conceptually similar to the menu displayed when the user performs a -"right-click" on a PC. You should use a context menu to provide the user access to -actions that pertain to a specific item in the user interface. On Android, a context menu is -displayed when the user performs a "long press" (press and hold) on an item.</p> +<p>A contextual menu offers actions that affect a specific item or context frame in the UI. You +can provide a context menu for any view, but they are most often used for items in a {@link +android.widget.ListView}, {@link android.widget.GridView}, or other view collections in which +the user can perform direct actions on each item.</p> -<p>You can create a context menu for any View, though context menus are most often used for items in -a {@link android.widget.ListView}. When the user performs a long-press on an item in a ListView and -the list is registered to provide a context menu, the list item signals to the user that a context -menu is available by animating its background color—it transitions from -orange to white before opening the context menu. (The Contacts application demonstrates this -feature.)</p> +<p>There are two ways to provide contextual actions:</p> +<ul> + <li>In a <a href="#FloatingContextMenu">floating context menu</a>. A menu appears as a +floating list of menu items (similar to a dialog) when the user performs a long-click (press and +hold) on a view that declares support for a context menu. Users can perform a contextual +action on one item at a time.</li> + + <li>In the <a href="#CAB">contextual action mode</a>. This mode is a system implementation of +{@link android.view.ActionMode} that displays a <em>contextual action bar</em> at the top of the +screen with action items that affect the selected item(s). When this mode is active, users +can perform an action on multiple items at once (if your app allows it).</li> +</ul> -<div class="sidebox-wrapper"> -<div class="sidebox"> -<h3>Register a ListView</h3> -<p>If your activity uses a {@link android.widget.ListView} and -you want all list items to provide a context menu, register all items for a context -menu by passing the {@link android.widget.ListView} to {@link -android.app.Activity#registerForContextMenu(View) registerForContextMenu()}. For -example, if you're using a {@link android.app.ListActivity}, register all list items like this:</p> -<p><code>registerForContextMenu({@link android.app.ListActivity#getListView()});</code></p> -</div> -</div> +<p class="note"><strong>Note:</strong> The contextual action mode is available on Android 3.0 (API +level 11) and higher and is the preferred technique for displaying contextual actions when +available. If your app supports versions lower than 3.0 then you should fall back to a floating +context menu on those devices.</p> -<p>In order for a View to provide a context menu, you must "register" the view for a context -menu. Call {@link android.app.Activity#registerForContextMenu(View) registerForContextMenu()} and -pass it the {@link android.view.View} you want to give a context menu. When this View then -receives a long-press, it displays a context menu.</p> -<p>To define the context menu's appearance and behavior, override your activity's context menu -callback methods, {@link android.app.Activity#onCreateContextMenu(ContextMenu,View,ContextMenuInfo) -onCreateContextMenu()} and -{@link android.app.Activity#onContextItemSelected(MenuItem) onContextItemSelected()}.</p> +<h3 id="FloatingContextMenu">Creating a floating context menu</h3> -<p>For example, here's an {@link -android.app.Activity#onCreateContextMenu(ContextMenu,View,ContextMenuInfo) -onCreateContextMenu()} that uses the {@code context_menu.xml} menu resource:</p> +<p>To provide a floating context menu:</p> +<ol> + <li>Register the {@link android.view.View} to which the context menu should be associated by +calling {@link android.app.Activity#registerForContextMenu(View) registerForContextMenu()} and pass +it the {@link android.view.View}. + <p>If your activity uses a {@link android.widget.ListView} or {@link android.widget.GridView} and +you want each item to provide the same context menu, register all items for a context menu by +passing the {@link android.widget.ListView} or {@link android.widget.GridView} to {@link +android.app.Activity#registerForContextMenu(View) registerForContextMenu()}.</p> +</li> + + <li>Implement the {@link +android.view.View.OnCreateContextMenuListener#onCreateContextMenu onCreateContextMenu()} method +in your {@link android.app.Activity} or {@link android.app.Fragment}. + <p>When the registered view receives a long-click event, the system calls your {@link +android.view.View.OnCreateContextMenuListener#onCreateContextMenu onCreateContextMenu()} +method. This is where you define the menu items, usually by inflating a menu resource. For +example:</p> <pre> @Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { - super.onCreateContextMenu(menu, v, menuInfo); - MenuInflater inflater = getMenuInflater(); - inflater.inflate(R.menu.context_menu, menu); + super.onCreateContextMenu(menu, v, menuInfo); + MenuInflater inflater = getMenuInflater(); + inflater.inflate(R.menu.context_menu, menu); } </pre> -<p>{@link android.view.MenuInflater} is used to inflate the context menu from a <a -href="{@docRoot}guide/topics/resources/menu-resource.html">menu resource</a>. (You can also use -{@link android.view.Menu#add(int,int,int,int) add()} to add menu items.) The callback method +<p>{@link android.view.MenuInflater} allows you to inflate the context menu from a <a +href="{@docRoot}guide/topics/resources/menu-resource.html">menu resource</a>. The callback method parameters include the {@link android.view.View} that the user selected and a {@link android.view.ContextMenu.ContextMenuInfo} object that provides -additional information about the item selected. You might use these parameters to determine -which context menu should be created, but in this example, all context menus for the activity are -the same.</p> +additional information about the item selected. If your activity has several views that each provide +a different context menu, you might use these parameters to determine which context menu to +inflate.</p> +</li> -<p>Then when the user selects an item from the context menu, the system calls {@link -android.app.Activity#onContextItemSelected(MenuItem) onContextItemSelected()}. Here is an example -of how you can handle selected items:</p> +<li>Implement {@link android.app.Activity#onContextItemSelected(MenuItem) +onContextItemSelected()}. + <p>When the user selects a menu item, the system calls this method so you can perform the +appropriate action. For example:</p> <pre> @Override public boolean onContextItemSelected(MenuItem item) { - AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo(); - switch (item.getItemId()) { - case R.id.edit: - editNote(info.id); - return true; - case R.id.delete: - deleteNote(info.id); - return true; - default: - return super.onContextItemSelected(item); - } + AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo(); + switch (item.getItemId()) { + case R.id.edit: + editNote(info.id); + return true; + case R.id.delete: + deleteNote(info.id); + return true; + default: + return super.onContextItemSelected(item); + } } </pre> -<p>The structure of this code is similar to the example for <a href="#options-menu">Creating an -Options Menu</a>, in which {@link android.view.MenuItem#getItemId()} queries the ID for the selected -menu item and a switch statement matches the item to the IDs that are defined in the menu resource. -And like the options menu example, the default statement calls the super class in case it -can handle menu items not handled here, if necessary.</p> +<p>The {@link android.view.MenuItem#getItemId()} method queries the ID for +the selected menu item, which you should assign to each menu item in XML using the {@code +android:id} attribute, as shown in the section about <a href="#xml">Defining a Menu in +XML</a>.</p> + +<p>When you successfully handle a menu item, return {@code true}. If you don't handle the menu item, +you should pass the menu item to the superclass implementation. If your activity includes fragments, +the activity receives this callback first. By calling the superclass when unhandled, the system +passes the event to the respective callback method in each fragment, one at a time (in the order +each fragment was added) until {@code true} or {@code false} is returned. (The default +implementation for {@link android.app.Activity} and {@code android.app.Fragment} return {@code +false}, so you should always call the superclass when unhandled.)</p> +</li> +</ol> + + +<h3 id="CAB">Using the contextual action mode</h3> -<p>In this example, the selected item is an item from a {@link android.widget.ListView}. To -perform an action on the selected item, the application needs to know the list -ID for the selected item (it's position in the ListView). To get the ID, the application calls -{@link android.view.MenuItem#getMenuInfo()}, which returns a {@link -android.widget.AdapterView.AdapterContextMenuInfo} object that includes the list ID for the -selected item in the {@link android.widget.AdapterView.AdapterContextMenuInfo#id id} field. The -local methods <code>editNote()</code> and <code>deleteNote()</code> methods accept this list ID to -perform an action on the data specified by the list ID.</p> +<p>The contextual action mode is a system implementation of {@link android.view.ActionMode} that +focuses user interaction toward performing contextual actions. When a +user enables this mode by selecting an item, a <em>contextual action bar</em> appears at the top of +the screen to present actions the user can perform on the currently selected item(s). While this +mode is enabled, the user can select multiple items (if you allow it), deselect items, and continue +to navigate within the activity (as much as you're willing to allow). The action mode is disabled +and the contextual action bar disappears when the user deselects all items, presses the BACK button, +or selects the <em>Done</em> action on the left side of the bar.</p> -<p class="note"><strong>Note:</strong> Items in a context menu do not support icons or shortcut -keys.</p> +<p class="note"><strong>Note:</strong> The contextual action bar is not necessarily +associated with the <a href="{@docRoot}guide/topics/ui/actionbar.html">action bar</a>. They operate +independently, even though the contextual action bar visually overtakes the action bar +position.</p> +<p>If you're developing for Android 3.0 (API level 11) or higher, you +should usually use the contextual action mode to present contextual actions, instead of the <a +href="#FloatingContextMenu">floating context menu</a>.</p> +<p>For views that provide contextual actions, you should usually invoke the contextual action mode +upon one of two events (or both):</p> +<ul> + <li>The user performs a long-click on the view.</li> + <li>The user selects a checkbox or similar UI component within the view.</li> +</ul> + +<p>How your application invokes the contextual action mode and defines the behavior for each +action depends on your design. There are basically two designs:</p> +<ul> + <li>For contextual actions on individual, arbitrary views.</li> + <li>For batch contextual actions on groups of items in a {@link +android.widget.ListView} or {@link android.widget.GridView} (allowing the user to select multiple +items and perform an action on them all).</li> +</ul> -<h2 id="submenu">Creating Submenus</h2> +<p>The following sections describe the setup required for each scenario.</p> -<p>A submenu is a menu that the user can open by selecting an item in another menu. You can add a -submenu to any menu (except a submenu). Submenus are useful when your application has a lot of -functions that can be organized into topics, like items in a PC application's menu bar (File, Edit, -View, etc.).</p> -<p>When creating your <a href="{@docRoot}guide/topics/resources/menu-resource.html">menu -resource</a>, you can create a submenu by adding a {@code <menu>} element as the child of an -{@code <item>}. For example:</p> +<h4 id="CABforViews">Enabling the contextual action mode for individual views</h4> +<p>If you want to invoke the contextual action mode only when the user selects specific +views, you should:</p> +<ol> + <li>Implement the {@link android.view.ActionMode.Callback} interface. In its callback methods, you +can specify the actions for the contextual action bar, respond to click events on action items, and +handle other lifecycle events for the action mode.</li> + <li>Call {@link android.app.Activity#startActionMode startActionMode()} when you want to show the +bar (such as when the user long-clicks the view).</li> +</ol> + +<p>For example:</p> + +<ol> + <li>Implement the {@link android.view.ActionMode.Callback ActionMode.Callback} interface: <pre> -<?xml version="1.0" encoding="utf-8"?> -<menu xmlns:android="http://schemas.android.com/apk/res/android"> - <item android:id="@+id/file" - android:icon="@drawable/file" - android:title="@string/file" > - <!-- "file" submenu --> - <menu> - <item android:id="@+id/create_new" - android:title="@string/create_new" /> - <item android:id="@+id/open" - android:title="@string/open" /> - </menu> - </item> -</menu> +private ActionMode.Callback mActionModeCallback = new ActionMode.Callback() { + + // Called when the action mode is created; startActionMode() was called + @Override + public boolean onCreateActionMode(ActionMode mode, Menu menu) { + // Inflate a menu resource providing context menu items + MenuInflater inflater = mode.getMenuInflater(); + inflater.inflate(R.menu.context_menu, menu); + return true; + } + + // Called each time the action mode is shown. Always called after onCreateActionMode, but + // may be called multiple times if the mode is invalidated. + @Override + public boolean onPrepareActionMode(ActionMode mode, Menu menu) { + return false; // Return false if nothing is done + } + + // Called when the user selects a contextual menu item + @Override + public boolean onActionItemClicked(ActionMode mode, MenuItem item) { + switch (item.getItemId()) { + case R.id.menu_share: + shareCurrentItem(); + mode.finish(); // Action picked, so close the CAB + return true; + default: + return false; + } + } + + // Called when the user exits the action mode + @Override + public void onDestroyActionMode(ActionMode mode) { + mActionMode = null; + } +}; +</pre> + +<p>Notice that these event callbacks are almost exactly the same as the callbacks for the <a +href="#options-menu">options menu</a>, except each of these also pass the {@link +android.view.ActionMode} object associated with the event. You can use {@link +android.view.ActionMode} APIs to make various changes to the CAB, such as revise the title and +subtitle with {@link android.view.ActionMode#setTitle setTitle()} and {@link +android.view.ActionMode#setSubtitle setSubtitle()} (useful to indicate how many items are +selected).</p> + +<p>Also notice that the above sample sets the {@code mActionMode} variable null when the +action mode is destroyed. In the next step, you'll see how it's initialized and how saving +the member variable in your activity or fragment can be useful.</p> +</li> + + <li>Call {@link android.app.Activity#startActionMode startActionMode()} to enable the contextual +action mode when appropriate, such as in response to a long-click on a {@link +android.view.View}:</p> + +<pre> +someView.setOnLongClickListener(new View.OnLongClickListener() { + // Called when the user long-clicks on someView + public boolean onLongClick(View view) { + if (mActionMode != null) { + return false; + } + + // Start the CAB using the ActionMode.Callback defined above + mActionMode = getActivity().startActionMode(mActionModeCallback); + view.setSelected(true); + return true; + } +}); +</pre> + +<p>When you call {@link android.app.Activity#startActionMode startActionMode()}, the system returns +the {@link android.view.ActionMode} created. By saving this in a member variable, you can +make changes to the contextual action bar in response to other events. In the above sample, the +{@link android.view.ActionMode} is used to ensure that the {@link android.view.ActionMode} instance +is not recreated if it's already active, by checking whether the member is null before starting the +action mode.</p> +</li> +</ol> + + + +<h4 id="CABforListView">Enabling batch contextual actions in a ListView or GridView</h4> + +<p>If you have a collection of items in a {@link android.widget.ListView} or {@link +android.widget.GridView} (or another extension of {@link android.widget.AbsListView}) and want to +allow users to perform batch actions, you should:</p> + +<ul> + <li>Implement the {@link android.widget.AbsListView.MultiChoiceModeListener} interface and set it +for the view group with {@link android.widget.AbsListView#setMultiChoiceModeListener +setMultiChoiceModeListener()}. In the listener's callback methods, you can specify the actions +for the contextual action bar, respond to click events on action items, and handle other callbacks +inherited from the {@link android.view.ActionMode.Callback} interface.</li> + + <li>Call {@link android.widget.AbsListView#setChoiceMode setChoiceMode()} with the {@link +android.widget.AbsListView#CHOICE_MODE_MULTIPLE_MODAL} argument.</li> +</ul> + +<p>For example:</p> + +<pre> +ListView listView = getListView(); +listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE_MODAL); +listView.setMultiChoiceModeListener(new MultiChoiceModeListener() { + + @Override + public void onItemCheckedStateChanged(ActionMode mode, int position, + long id, boolean checked) { + // Here you can do something when items are selected/de-selected, + // such as update the title in the CAB + } + + @Override + public boolean onActionItemClicked(ActionMode mode, MenuItem item) { + // Respond to clicks on the actions in the CAB + switch (item.getItemId()) { + case R.id.menu_delete: + deleteSelectedItems(); + mode.finish(); // Action picked, so close the CAB + return true; + default: + return false; + } + } + + @Override + public boolean onCreateActionMode(ActionMode mode, Menu menu) { + // Inflate the menu for the CAB + MenuInflater inflater = mode.getMenuInflater(); + inflater.inflate(R.menu.context, menu); + return true; + } + + @Override + public void onDestroyActionMode(ActionMode mode) { + // Here you can make any necessary updates to the activity when + // the CAB is removed. By default, selected items are deselected/unchecked. + } + + @Override + public boolean onPrepareActionMode(ActionMode mode, Menu menu) { + // Here you can perform updates to the CAB due to + // an {@link android.view.ActionMode#invalidate} request + return false; + } +}); +</pre> + +<p>That's it. Now when the user selects an item with a long-click, the system calls the {@link +android.widget.AbsListView.MultiChoiceModeListener#onCreateActionMode onCreateActionMode()} +method and displays the contextual action bar with the specified actions. While the contextual +action bar is visible, users can select additional items.</p> + +<p>In some cases in which the contextual actions provide common action items, you might +want to add a checkbox or a similar UI element that allows users to select items, because they +might not discover the long-click behavior. When a user selects the checkbox, you +can invoke the contextual action mode by setting the respective list item to the checked +state with {@link android.widget.AbsListView#setItemChecked setItemChecked()}.</p> + + + + +<h2 id="PopupMenu">Creating a Popup Menu</h2> + +<div class="figure" style="width:220px"> +<img src="{@docRoot}images/ui/popupmenu.png" alt="" /> +<p><strong>Figure 4.</strong> A popup menu in the Gmail app, anchored to the overflow +button at the top-right.</p> +</div> + +<p>A {@link android.widget.PopupMenu} is a modal menu anchored to a {@link android.view.View}. +It appears below the anchor view if there is room, or above the view otherwise. It's useful for:</p> +<ul> + <li>Providing an overflow-style menu for actions that <em>relate to</em> specific content (such as +Gmail's email headers, shown in figure 4). + <p class="note"><strong>Note:</strong> This is not the same as a context menu, which is +generally for actions that <em>affect</em> selected content. For actions that affect selected +content, use the <a href="#CAB">contextual action mode</a> or <a +href="#FloatingContextMenu">floating context menu</a>.</p></li> + <li>Providing a second part of a command sentence (such as a button marked "Add" +that produces a popup menu with different "Add" options).</li> + <li>Providing a drop-down similar to {@link android.widget.Spinner} that does not retain +a persistent selection.</li> +</ul> + + +<p class="note"><strong>Note:</strong> {@link android.widget.PopupMenu} is available with API +level 11 and higher.</p> + +<p>If you <a href="#xml">define your menu in XML</a>, here's how you can show the popup menu:</p> +<ol> + <li>Instantate a {@link android.widget.PopupMenu} with its constructor, which takes the +current application {@link android.content.Context} and the {@link android.view.View} to which the +menu should be anchored.</li> + <li>Use {@link android.view.MenuInflater} to inflate your menu resource into the {@link +android.view.Menu} object returned by {@link +android.widget.PopupMenu#getMenu() PopupMenu.getMenu()}. On API level 14 and above, you can use +{@link android.widget.PopupMenu#inflate PopupMenu.inflate()} instead.</li> + <li>Call {@link android.widget.PopupMenu#show() PopupMenu.show()}.</li> +</ol> + +<p>For example, here's a button with the {@link android.R.attr#onClick android:onClick} attribute +that shows a popup menu:</p> + +<pre> +<ImageButton + android:layout_width="wrap_content" + android:layout_height="wrap_content" + android:src="@drawable/ic_overflow_holo_dark" + android:contentDescription="@string/descr_overflow_button" + android:onClick="showPopup" /> +</pre> + +<p>The activity can then show the popup menu like this:</p> + +<pre> +public void showPopup(View v) { + PopupMenu popup = new PopupMenu(this, v); + MenuInflater inflater = popup.getMenuInflater(); + inflater.inflate(R.menu.actions, popup.getMenu()); + popup.show(); +} </pre> -<p>When the user selects an item from a submenu, the parent menu's respective on-item-selected -callback method receives the event. For instance, if the above menu is applied as an Options Menu, -then the {@link android.app.Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected()} method -is called when a submenu item is selected.</p> +<p>In API level 14 and higher, you can combine the two lines that inflate the menu with {@link +android.widget.PopupMenu#inflate PopupMenu.inflate()}.</p> + +<p>The menu is dismissed when the user selects an item or touches outside the menu +area. You can listen for the dismiss event using {@link +android.widget.PopupMenu.OnDismissListener}.</p> + +<h3 id="PopupEvents">Handling click events</h3> -<p>You can also use {@link android.view.Menu#addSubMenu(int,int,int,int) addSubMenu()} to -dynamically add a {@link android.view.SubMenu} to an existing {@link android.view.Menu}. This -returns the new {@link android.view.SubMenu} object, to which you can add -submenu items, using {@link android.view.Menu#add(int,int,int,int) add()}</p> +<p>To perform an +action when the user selects a menu item, you must implement the {@link +android.widget.PopupMenu.OnMenuItemClickListener} interface and register it with your {@link +android.widget.PopupMenu} by calling {@link android.widget.PopupMenu#setOnMenuItemClickListener +setOnMenuItemclickListener()}. When the user selects an item, the system calls the {@link +android.widget.PopupMenu.OnMenuItemClickListener#onMenuItemClick onMenuItemClick()} callback in +your interface.</p> +<p>For example:</p> +<pre> +public void showMenu(View v) { + PopupMenu popup = new PopupMenu(this, v); -<h2 id="features">Other Menu Features</h2> + // This activity implements OnMenuItemClickListener + popup.setOnMenuItemClickListener(this); + popup.inflate(R.menu.actions); + popup.show(); +} + +@Override +public boolean onMenuItemClick(MenuItem item) { + switch (item.getItemId()) { + case R.id.archive: + archive(item); + return true; + case R.id.delete: + delete(item); + return true; + default: + return false; + } +} +</pre> -<p>Here are some other features that you can apply to most menu items.</p> -<h3 id="groups">Menu groups</h3> +<h2 id="groups">Creating Menu Groups</h2> <p>A menu group is a collection of menu items that share certain traits. With a group, you can:</p> @@ -473,38 +842,41 @@ android.view.Menu#add(int,int,int,int) add()} method.</p> <pre> <?xml version="1.0" encoding="utf-8"?> <menu xmlns:android="http://schemas.android.com/apk/res/android"> - <item android:id="@+id/item1" - android:icon="@drawable/item1" - android:title="@string/item1" /> + <item android:id="@+id/menu_save" + android:icon="@drawable/menu_save" + android:title="@string/menu_save" /> <!-- menu group --> - <group android:id="@+id/group1"> - <item android:id="@+id/groupItem1" - android:title="@string/groupItem1" /> - <item android:id="@+id/groupItem2" - android:title="@string/groupItem2" /> + <group android:id="@+id/group_delete"> + <item android:id="@+id/menu_archive" + android:title="@string/menu_archive" /> + <item android:id="@+id/menu_delete" + android:title="@string/menu_delete" /> </group> </menu> </pre> -<p>The items that are in the group appear the same as the first item that is not in a -group—all three items in the menu are siblings. However, you can modify the traits of the two -items in the group by referencing the group ID and using the methods listed above.</p> +<p>The items that are in the group appear at the same level as the first item—all three items +in the menu are siblings. However, you can modify the traits of the two +items in the group by referencing the group ID and using the methods listed above. The system +will also never separate grouped items. For example, if you declare {@code +android:showAsAction="ifRoom"} for each item, they will either both appear in the action +bar or both appear in the action overflow.</p> -<h3 id="checkable">Checkable menu items</h3> +<h3 id="checkable">Using checkable menu items</h3> <div class="figure" style="width:200px"> <img src="{@docRoot}images/radio_buttons.png" height="333" alt="" /> - <p class="img-caption"><strong>Figure 3.</strong> Screenshot of a submenu with checkable + <p class="img-caption"><strong>Figure 5.</strong> Screenshot of a submenu with checkable items.</p> </div> <p>A menu can be useful as an interface for turning options on and off, using a checkbox for stand-alone options, or radio buttons for groups of -mutually exclusive options. Figure 2 shows a submenu with items that are checkable with radio +mutually exclusive options. Figure 5 shows a submenu with items that are checkable with radio buttons.</p> -<p class="note"><strong>Note:</strong> Menu items in the Icon Menu (from the Options Menu) cannot +<p class="note"><strong>Note:</strong> Menu items in the Icon Menu (from the options menu) cannot display a checkbox or radio button. If you choose to make items in the Icon Menu checkable, you must manually indicate the checked state by swapping the icon and/or text each time the state changes.</p> @@ -550,15 +922,15 @@ user selected it) with {@link android.view.MenuItem#isChecked()} and then set th <pre> @Override public boolean onOptionsItemSelected(MenuItem item) { - switch (item.getItemId()) { - case R.id.vibrate: - case R.id.dont_vibrate: - if (item.isChecked()) item.setChecked(false); - else item.setChecked(true); - return true; - default: - return super.onOptionsItemSelected(item); - } + switch (item.getItemId()) { + case R.id.vibrate: + case R.id.dont_vibrate: + if (item.isChecked()) item.setChecked(false); + else item.setChecked(true); + return true; + default: + return super.onOptionsItemSelected(item); + } } </pre> @@ -575,30 +947,8 @@ you should store the data using <a href="{@docRoot}guide/topics/data/data-storage.html#pref">Shared Preferences</a>.</p> -<h3 id="shortcuts">Shortcut keys</h3> - -<p>To facilitate quick access to items in the Options Menu when the user's device has a hardware -keyboard, you can add quick-access shortcut keys using letters and/or numbers, with the -{@code android:alphabeticShortcut} and {@code android:numericShortcut} attributes in the {@code -<item>} element. You can also use the methods {@link -android.view.MenuItem#setAlphabeticShortcut(char)} and {@link -android.view.MenuItem#setNumericShortcut(char)}. Shortcut keys are <em>not</em> -case sensitive.</p> - -<p>For example, if you apply the "s" character as an alphabetic shortcut to a "save" menu item, then -when the menu is open (or while the user holds the MENU button) and the user presses the "s" key, -the "save" menu item is selected.</p> - -<p>This shortcut key is displayed as a tip in the menu item, below the menu item name -(except for items in the Icon Menu, which are displayed only if the user holds the MENU -button).</p> - -<p class="note"><strong>Note:</strong> Shortcut keys for menu items only work on devices with a -hardware keyboard. Shortcuts cannot be added to items in a Context Menu.</p> - - -<h3 id="intents">Dynamically adding menu intents</h3> +<h2 id="intents">Adding Menu Items Based on an Intent</h2> <p>Sometimes you'll want a menu item to launch an activity using an {@link android.content.Intent} (whether it's an activity in your application or another application). When you know the intent you @@ -671,7 +1021,7 @@ addIntentOptions()}, it overrides any and all menu items by the menu group speci argument.</p> -<h4>Allowing your activity to be added to other menus</h4> +<h3 id="AllowingToAdd">Allowing your activity to be added to other menus</h3> <p>You can also offer the services of your activity to other applications, so your application can be included in the menu of others (reverse the roles described above).</p> @@ -681,7 +1031,7 @@ filter as usual, but be sure to include the {@link android.content.Intent#CATEGO and/or {@link android.content.Intent#CATEGORY_SELECTED_ALTERNATIVE} values for the intent filter category. For example:</p> <pre> -<intent-filter label="Resize Image"> +<intent-filter label="@string/resize_image"> ... <category android:name="android.intent.category.ALTERNATIVE" /> <category android:name="android.intent.category.SELECTED_ALTERNATIVE" /> diff --git a/docs/html/images/ui/menu-context.png b/docs/html/images/ui/menu-context.png Binary files differnew file mode 100644 index 0000000..f6975fb --- /dev/null +++ b/docs/html/images/ui/menu-context.png diff --git a/docs/html/images/ui/popupmenu.png b/docs/html/images/ui/popupmenu.png Binary files differnew file mode 100644 index 0000000..5c99821 --- /dev/null +++ b/docs/html/images/ui/popupmenu.png |