1page.title=<activity-alias> 2parent.title=The AndroidManifest.xml File 3parent.link=manifest-intro.html 4@jd:body 5 6<dl class="xml"> 7<dt>syntax:</dt> 8<dd><pre class="stx"><activity-alias android:<a href="#enabled">enabled</a>=["true" | "false"] 9 android:<a href="#exported">exported</a>=["true" | "false"] 10 android:<a href="#icon">icon</a>="<i>drawable resource</i>" 11 android:<a href="#label">label</a>="<i>string resource</i>" 12 android:<a href="#nm">name</a>="<i>string</i>" 13 android:<a href="#prmsn">permission</a>="<i>string</i>" 14 android:<a href="#trgt">targetActivity</a>="<i>string</i>" > 15 . . . 16</activity-alias></pre></dd> 17 18<dt>contained in:</dt> 19<dd><code><a href="{@docRoot}guide/topics/manifest/application-element.html"><application></a></code></dd> 20 21<dt>can contain:</dt> 22<dd><code><a href="{@docRoot}guide/topics/manifest/intent-filter-element.html"><intent-filter></a></code> 23<br/><code><a href="{@docRoot}guide/topics/manifest/meta-data-element.html"><meta-data></a></code></dd> 24 25<dt>description:</dt> 26<dd>An alias for an activity, named by the {@code targetActivity} 27attribute. The target must be in the same application as the 28alias and it must be declared before the alias in the manifest. 29 30<p> 31The alias presents the target activity as a independent entity. 32It can have its own set of intent filters, and they, rather than the 33intent filters on the target activity itself, determine which intents 34can activate the target through the alias and how the system 35treats the alias. For example, the intent filters on the alias may 36specify the "<code>{@link android.content.Intent#ACTION_MAIN 37android.intent.action.MAIN}</code>" 38and "<code>{@link android.content.Intent#CATEGORY_LAUNCHER 39android.intent.category.LAUNCHER}</code>" flags, causing it to be 40represented in the application launcher, even though none of the 41filters on the target activity itself set these flags. 42</p> 43 44<p> 45With the exception of {@code targetActivity}, {@code <activity-alias>} 46attributes are a subset of <code><a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a></code> attributes. 47For attributes in the subset, none of the values set for the target carry over 48to the alias. However, for attributes not in the subset, the values set for 49the target activity also apply to the alias. 50</p></dd> 51 52<dt>attributes:</dt> 53<dd><dl class="attr"> 54<dt><a name="enabled"></a>{@code android:enabled}</dt> 55<dd>Whether or not the target activity can be instantiated by the system through 56this alias — "{@code true}" if it can be, and "{@code false}" if not. 57The default value is "{@code true}". 58 59<p> 60The <code><a href="{@docRoot}guide/topics/manifest/application-element.html"><application></a></code> element has its own 61<code><a href="{@docRoot}guide/topics/manifest/application-element.html#enabled">enabled</a></code> attribute that applies to all 62application components, including activity aliases. The 63<code><a href="{@docRoot}guide/topics/manifest/application-element.html"><application></a></code> and {@code <activity-alias>} 64attributes must both be "{@code true}" for the system to be able to instantiate 65the target activity through the alias. If either is "{@code false}", the alias 66does not work. 67</p></dd> 68 69<dt><a name="exported"></a>{@code android:exported}</dt> 70<dd>Whether or not components of other applications can launch the target activity 71through this alias — "{@code true}" if they can, and "{@code false}" if not. 72If "{@code false}", the target activity can be launched through the alias only by 73components of the same application as the alias or applications with the same user ID. 74 75<p> 76The default value depends on whether the alias contains intent filters. The 77absence of any filters means that the activity can be invoked through the alias 78only by specifying the exact name of the alias. This implies that the alias 79is intended only for application-internal use (since others would not know its name) 80— so the default value is "{@code false}". 81On the other hand, the presence of at least one filter implies that the alias 82is intended for external use — so the default value is "{@code true}". 83</p></dd> 84 85<dt><a name="icon"></a>{@code android:icon}</dt> 86<dd>An icon for the target activity when presented to users through the alias. 87See the <code><a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a></code> element's 88<code><a href="{@docRoot}guide/topics/manifest/activity-element.html#icon">icon</a></code> attribute for more information. 89 90<dt><a name="label"></a>{@code android:label}</dt> 91<dd>A user-readable label for the alias when presented to users through the alias. 92See the the <code><a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a></code> element's 93<code><a href="{@docRoot}guide/topics/manifest/activity-element.html#label">label</a></code> attribute for more information. 94</p></dd> 95 96<dt><a name="nm">{@code android:name}</dt> 97<dd>A unique name for the alias. The name should resemble a fully 98qualified class name. But, unlike the name of the target activity, 99the alias name is arbitrary; it does not refer to an actual class. 100</p></dd> 101 102<dt><a name="prmsn"></a>{@code android:permission}</dt> 103<dd>The name of a permission that clients must have to launch the target activity 104or get it to do something via the alias. If a caller of 105<code>{@link android.content.Context#startActivity startActivity()}</code> or 106<code>{@link android.app.Activity#startActivityForResult startActivityForResult()}</code> 107has not been granted the specified permission, the target activity will not be 108activated. 109 110<p>This attribute supplants any permission set for the target activity itself. If 111it is not set, a permission is not needed to activate the target through the alias. 112</p> 113 114<p> 115For more information on permissions, see the 116<a href="{@docRoot}guide/topics/manifest/manifest-intro.html#perms">Permissions</a> 117section in the introduction. 118</p></dd> 119 120<dt><a name="trgt"></a>{@code android:targetActivity}</dt> 121<dd>The name of the activity that can be activated through the alias. 122This name must match the {@code name} attribute of an 123<code><a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a></code> element that precedes 124the alias in the manifest. 125</p></dd> 126</dl></dd> 127 128<!-- ##api level indication## --> 129<dt>introduced in:</dt> 130<dd>API Level 1</dd> 131 132<dt>see also:</dt> 133<dd><code><a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a></code></dd> 134 135</dl>