M7350/base/docs/html/guide/topics/manifest/service-element.jd
2024-09-09 08:52:07 +00:00

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page.title=<service>
@jd:body
<dl class="xml">
<dt>syntax:</dt>
<dd><pre class="stx">&lt;service android:<a href="#enabled">enabled</a>=["true" | "false"]
android:<a href="#exported">exported[</a>="true" | "false"]
android:<a href="#icon">icon</a>="<i>drawable resource</i>"
android:<a href="#label">label</a>="<i>string resource</i>"
android:<a href="#nm">name</a>="<i>string</i>"
android:<a href="#prmsn">permission</a>="<i>string</i>"
android:<a href="#proc">process</a>="<i>string</i>" &gt;
. . .
&lt;/service&gt;</pre></dd>
<dt>contained in:</dt>
<dd><code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code></dd>
<dt>can contain:</dt>
<dd><code><a href="{@docRoot}guide/topics/manifest/intent-filter-element.html">&lt;intent-filter&gt;</a></code>
<br/><code><a href="{@docRoot}guide/topics/manifest/meta-data-element.html">&lt;meta-data&gt;</a></code></dd>
<dt>description:</dt>
<dd>Declares a service (a {@link android.app.Service} subclass) as one
of the application's components. Unlike activities, services lack a
visual user interface. They're used to implement long-running background
operations or a rich communications API that can be called by other
applications.
<p>
All services must be represented by {@code &lt;service&gt;} elements in
the manifest file. Any that are not declared there will not be seen
by the system and will never be run.
</p></dd>
<dt>attributes:</dt>
<dd><dl class="attr">
<dt><a name="enabled"></a>{@code android:enabled}</dt>
<dd>Whether or not the service can be instantiated by the system &mdash;
"{@code true}" if it can be, and "{@code false}" if not. The default value
is "{@code true}".
<p>
The <code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> element has its own
<code><a href="{@docRoot}guide/topics/manifest/application-element.html#enabled">enabled</a></code> attribute that applies to all
application components, including services. The
<code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> and {@code &lt;service&gt;}
attributes must both be "{@code true}" (as they both
are by default) for the service to be enabled. If either is
"{@code false}", the service is disabled; it cannot be instantiated.
</p></dd>
<dt><a name="exported"></a>{@code android:exported}</dt>
<dd>Whether or not components of other applications can invoke
the service or interact with it &mdash; "{@code true}" if they can, and
"{@code false}" if not. When the value is "{@code false}", only
components of the same application or applications
with the same user ID can start the service or bind to it.
<p>
The default value depends on whether the service contains intent filters. The
absence of any filters means that it can be invoked only by specifying
its exact class name. This implies that the service is intended only for
application-internal use (since others would not know the class name). So in
this case, the default value is "{@code false}".
On the other hand, the presence of at least one filter implies that the service
is intended for external use, so the default value is "{@code true}".
</p>
<p>
This attribute is not the only way to limit the exposure of a service to other
applications. You can also use a permission to limit the external entities that
can interact with the service (see the <code><a href="{@docRoot}guide/topics/manifest/service-element.html#prmsn">permission</a></code>
attribute).
</p></dd>
<dt><a name="icon"></a>{@code android:icon}</dt>
<dd>An icon representing the service. This attribute must be set as a
reference to a drawable resource containing the image definition.
If it is not set, the icon specified for the application
as a whole is used instead (see the <code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code>
element's <code><a href="{@docRoot}guide/topics/manifest/application-element.html#icon">icon</a></code> attribute).
</p>
<p>
The service's icon &mdash; whether set here or by the
<code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> element &mdash; is also the
default icon for all the service's intent filters (see the
<code><a href="{@docRoot}guide/topics/manifest/intent-filter-element.html">&lt;intent-filter&gt;</a></code> element's
<code><a href="{@docRoot}guide/topics/manifest/intent-filter-element.html#icon">icon</a></code> attribute).
</p></dd>
<dt><a name="label"></a>{@code android:label}</dt>
<dd>A name for the service that can be displayed to users.
If this attribute is not set, the label set for the application as a whole is
used instead (see the <code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> element's
<code><a href="{@docRoot}guide/topics/manifest/application-element.html#label">label</a></code> attribute).
<p>
The service's label &mdash; whether set here or by the
<code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> element &mdash; is also the
default label for all the service's intent filters (see the
<code><a href="{@docRoot}guide/topics/manifest/intent-filter-element.html">&lt;intent-filter&gt;</a></code> element's
<code><a href="{@docRoot}guide/topics/manifest/intent-filter-element.html#label">label</a></code> attribute).
</p>
<p>
The label should be set as a reference to a string resource, so that
it can be localized like other strings in the user interface.
However, as a convenience while you're developing the application,
it can also be set as a raw string.
</p></dd>
<dt><a name="nm"></a>{@code android:name}</dt>
<dd>The name of the {@link android.app.Service} subclass that implements
the service. This should be a fully qualified class name (such as,
"{@code com.example.project.RoomService}"). However, as a shorthand, if
the first character of the name is a period (for example, "{@code .RoomService}"),
it is appended to the package name specified in the
<code><a href="{@docRoot}guide/topics/manifest/manifest-element.html">&lt;manifest&gt;</a></code> element.
<p>
There is no default. The name must be specified.
</p></dd>
<dt><a name="prmsn"></a>{@code android:permission}</dt>
<dd>The name of a permission that that an entity must have in order to
launch the service or bind to it. If a caller of
<code>{@link android.content.Context#startService startService()}</code>,
<code>{@link android.content.Context#bindService bindService()}</code>, or
<code>{@link android.content.Context#stopService stopService()}</code>,
has not been granted this permission, the method will not work and the
Intent object will not be delivered to the service.
<p>
If this attribute is not set, the permission set by the
<code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> element's
<code><a href="{@docRoot}guide/topics/manifest/application-element.html#prmsn">permission</a></code>
attribute applies to the service. If neither attribute is set, the service is
not protected by a permission.
</p>
<p>
For more information on permissions, see the
<a href="{@docRoot}guide/topics/manifest/manifest-intro.html#sectperm">Permissions</a>
section in the introduction and a separate document,
<a href="{@docRoot}guide/topics/security/security.html">Security and Permissions</a>.
</p></dd>
<dt><a name="proc"></a>{@code android:process}</dt>
<dd>The name of the process where the service is to run. Normally,
all components of an application run in the default process created for the
application. It has the same name as the application package. The
<code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code> element's
<code><a href="{@docRoot}guide/topics/manifest/application-element.html#proc">process</a></code>
attribute can set a different
default for all components. But component can override the default
with its own {@code process} attribute, allowing you to spread your
application across multiple processes.
<p>
If the name assigned to this attribute begins with a colon (':'), a new
process, private to the application, is created when it's needed and
the service runs in that process.
If the process name begins with a lowercase character, the service will run
in a global process of that name, provided that it has permission to do so.
This allows components in different applications to share a process, reducing
resource usage.
</p></dd>
</dl></dd>
<dt>see also:</dt>
<dd><code><a href="{@docRoot}guide/topics/manifest/application-element.html">&lt;application&gt;</a></code>
<br><code><a href="{@docRoot}guide/topics/manifest/activity-element.html">&lt;activity&gt;</a></code></dd>
<!-- ##api level indication## -->
<dt>introduced in:</dt>
<dd>API Level 1</dd>
</dl>