guide/components/services.jd

page.title=
@jd:body

<div id="qv-wrapper">
<ol id="qv">
<h2>  </h2>
<ol>
<li><a href="#Basics"> </a></li>
<ol>
  <li><a href="#Declaring">  </a></li>
</ol>
<li><a href="#CreatingAService">  </a>
  <ol>
    <li><a href="#ExtendingIntentService">IntentService  </a></li>
    <li><a href="#ExtendingService">  </a></li>
    <li><a href="#StartingAService"> </a></li>
    <li><a href="#Stopping"> </a></li>
  </ol>
</li>
<li><a href="#CreatingBoundService">  </a></li>
<li><a href="#Notifications">  </a></li>
<li><a href="#Foreground">  </a></li>
<li><a href="#Lifecycle">   </a>
<ol>
  <li><a href="#LifecycleCallbacks">   </a></li>
</ol>
</li>
</ol>

<h2>Key </h2>
<ol>
  <li>{@link android.app.Service}</li>
  <li>{@link android.app.IntentService}</li>
</ol>

<h2></h2>
<ol>
  <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/ServiceStartArguments.html">{@code
      ServiceStartArguments}</a></li>
  <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/LocalService.html">{@code
      LocalService}</a></li>
</ol>

<h2> </h2>
<ol>
<li><a href="{@docRoot}guide/components/bound-services.html"> </a></li>
</ol>

</div>


<p>{@link android.app.Service}
         .
      ,
    . ,
    ,    (IPC)   .
  ,    I/O
      .</p>

<p>     .</p>

<dl>
  <dt></dt>
  <dd> ""     (: )
{@link android.content.Context#startService startService()}   .
    ,        . ,
        .
       .  ,
   .</dd>
  <dt></dt>
  <dd> ""      {@link
android.content.Context#bindService bindService()}     .   -
         ,
        (IPC)   .
    .         ,
       .</dd>
</dl>

<p>         ,
      .     (  )     .
         . {@link
android.app.Service#onStartCommand onStartCommand()}        , {@link
android.app.Service#onBind onBind()}   .</p>

<p> ,
    ( ),
    .  {@link android.content.Intent}  . ,
         .
<a href="#Declaring">
</a>     .</p>

<p class="caution"><strong>:</strong>
  .      <strong></strong>,
   <strong></strong>(   ).  ,
 CPU         (  MP3
   ),           .
'  (ANR)'
          .</p>


<h2 id="Basics"> </h2>

<div class="sidebox-wrapper">
<div class="sidebox">
  <h3>      ?</h3>
  <p>        .
      . ,
.</p>
  <p>
   ,        .
      ,
{@link android.app.Activity#onCreate onCreate()}     {@link
android.app.Activity#onStart onStart()}    {@link android.app.Activity#onStop
onStop()}  . ,  {@link java.lang.Thread}
{@link android.os.AsyncTask}  {@link android.os.HandlerThread}   .     <a href="{@docRoot}guide/components/processes-and-threads.html#Threads">
</a>  .</p>
  <p>

     .</p>
</div>
</div>

<p>  {@link android.app.Service}    (
    ).

 ( ).        .</p>

<dl>
  <dt>{@link android.app.Service#onStartCommand onStartCommand()}</dt>
    <dd>        (: )
  .  {@link android.content.Context#startService
startService()}   .
.
  .  {@link android.app.Service#stopSelf stopSelf()}  {@link
android.content.Context#stopService stopService()}   (   ,
 ).</dd>
  <dt>{@link android.app.Service#onBind onBind()}</dt>
    <dd>
(  RPC  ).  {@link android.content.Context#bindService
bindService()}   .
  .  {@link android.os.IBinder}  .
 ,     null  .</dd>
  <dt>{@link android.app.Service#onCreate()}</dt>
    <dd>
  ({@link android.app.Service#onStartCommand onStartCommand()}
{@link android.app.Service#onBind onBind()}  ).     ,
.</dd>
  <dt>{@link android.app.Service#onDestroy()}</dt>
    <dd>            .
   ,   (listener, receiver)
    .     .</dd>
</dl>

<p>   {@link
android.content.Context#startService startService()}   ({@link
android.app.Service#onStartCommand onStartCommand()}  ),
 {@link android.app.Service#stopSelf()}
    {@link android.content.Context#stopService stopService()}        .</p>

<p>
{@link android.content.Context#bindService bindService()}    ( {@link
android.app.Service#onStartCommand onStartCommand()}  <em></em> ),
      .
.</p>

<p>Android
       .
       ,  <a href="#Foreground"> </a>  (  ),    .
 ,

   .
  .    ,
      (   {@link
android.app.Service#onStartCommand onStartCommand()}   .    ).
       <a href="{@docRoot}guide/components/processes-and-threads.html">  </a>
 .</p>

<p>
    .</p>


<h3 id="Declaring">  </h3>

<p>(   ) ,
  .</p>

<p>  <a href="{@docRoot}guide/topics/manifest/service-element.html">{@code &lt;service&gt;}</a>
<a href="{@docRoot}guide/topics/manifest/application-element.html">{@code &lt;application&gt;}</a>
    . :</p>

<pre>
&lt;manifest ... &gt;
  ...
  &lt;application ... &gt;
      &lt;service android:name=".ExampleService" /&gt;
      ...
  &lt;/application&gt;
&lt;/manifest&gt;
</pre>

<p>       <a href="{@docRoot}guide/topics/manifest/service-element.html">{@code &lt;service&gt;}</a>
  .</p>

<p><a href="{@docRoot}guide/topics/manifest/service-element.html">{@code &lt;service&gt;}</a>       .

   . <a href="{@docRoot}guide/topics/manifest/service-element.html#nm">{@code android:name}</a>
   .     .
      .
            (  <a href="http://android-developers.blogspot.com/2011/06/things-that-cannot-change.html">
   </a> ).

<p>   <strong>
{@link android.app.Service}       </strong>      .
        ,
      {@link
android.content.Intent}   ,      {@link
android.content.Intent#setPackage setPackage()}
  .</p>

<p>        .
<a href="{@docRoot}guide/topics/manifest/service-element.html#exported">{@code android:exported}</a>
     {@code "false"}  .          ,
       .</p>


<h2 id="CreatingStartedService">  </h2>

<p>     {@link
android.content.Context#startService startService()}  ,
{@link android.app.Service#onStartCommand onStartCommand()}      .</p>

<p>
         .
    . ,
{@link android.app.Service#stopSelf stopSelf()}
{@link android.content.Context#stopService stopService()}    .</p>

<p>  (: )   {@link
android.content.Context#startService startService()} , {@link android.content.Intent}
 .        .
{@link android.content.Intent} {@link android.app.Service#onStartCommand
onStartCommand()}  .</p>

<p>          .
        .   {@link
android.content.Context#startService startService()}  .    {@link
android.app.Service#onStartCommand onStartCommand()}
 .  ,
.</p>

<p class="caution"><strong>:</strong>
        . ,
           ,
      .      ,
     .</p>

<p>           .</p>
<dl>
  <dt>{@link android.app.Service}</dt>
  <dd>    .    ,
    .
,
   .</dd>
  <dt>{@link android.app.IntentService}</dt>
  <dd> {@link android.app.Service}  ,
        .
       .    {@link
android.app.IntentService#onHandleIntent onHandleIntent()}  ,
     .</dd>
</dl>

<p>
.</p>


<h3 id="ExtendingIntentService">IntentService  </h3>

<p>
(       ),
{@link android.app.IntentService}      .</p>

<p>{@link android.app.IntentService}    .</p>

<ul>
  <li>    {@link
android.app.Service#onStartCommand onStartCommand()}
.</li>
  <li>    {@link
android.app.IntentService#onHandleIntent onHandleIntent()}
 .</li>
  <li>
{@link android.app.Service#stopSelf}    .</li>
  <li>{@link android.app.IntentService#onBind onBind()}    null
 .</li>
  <li>{@link android.app.IntentService#onStartCommand
onStartCommand()}       ,  {@link
android.app.IntentService#onHandleIntent onHandleIntent()}   .</li>
</ul>

<p>            {@link
android.app.IntentService#onHandleIntent onHandleIntent()}
. (,       .)</p>

<p> {@link android.app.IntentService}    .</p>

<pre>
public class HelloIntentService extends IntentService {

  /**
   * A constructor is required, and must call the super {@link android.app.IntentService#IntentService}
   * constructor with a name for the worker thread.
   */
  public HelloIntentService() {
      super("HelloIntentService");
  }

  /**
   * The IntentService calls this method from the default worker thread with
   * the intent that started the service. When this method returns, IntentService
   * stops the service, as appropriate.
   */
  &#64;Override
  protected void onHandleIntent(Intent intent) {
      // Normally we would do some work here, like download a file.
      // For our sample, we just sleep for 5 seconds.
      long endTime = System.currentTimeMillis() + 5*1000;
      while (System.currentTimeMillis() &lt; endTime) {
          synchronized (this) {
              try {
                  wait(endTime - System.currentTimeMillis());
              } catch (Exception e) {
              }
          }
      }
  }
}
</pre>

<p>   .   {@link
android.app.IntentService#onHandleIntent onHandleIntent()} .</p>

<p>     -  {@link
android.app.IntentService#onCreate onCreate()}, {@link
android.app.IntentService#onStartCommand onStartCommand()}  {@link
android.app.IntentService#onDestroy onDestroy()}-    .
 {@link android.app.IntentService}       .</p>

<p>  {@link android.app.IntentService#onStartCommand onStartCommand()}
   (  {@link
android.app.IntentService#onHandleIntent onHandleIntent()}  ).</p>

<pre>
&#64;Override
public int onStartCommand(Intent intent, int flags, int startId) {
    Toast.makeText(this, "service starting", Toast.LENGTH_SHORT).show();
    return super.onStartCommand(intent,flags,startId);
}
</pre>

<p>{@link android.app.IntentService#onHandleIntent onHandleIntent()}
     {@link android.app.IntentService#onBind
onBind()}(        ).</p>

<p>   {@link android.app.Service}
         .     ,
         .</p>


<h3 id="ExtendingService">  </h3>

<p>     {@link android.app.IntentService}
    .
  (      ),
{@link android.app.Service}        .</p>

<p>     .  {@link
android.app.Service}  ,   {@link
android.app.IntentService}      .
          .</p>

<pre>
public class HelloService extends Service {
  private Looper mServiceLooper;
  private ServiceHandler mServiceHandler;

  // Handler that receives messages from the thread
  private final class ServiceHandler extends Handler {
      public ServiceHandler(Looper looper) {
          super(looper);
      }
      &#64;Override
      public void handleMessage(Message msg) {
          // Normally we would do some work here, like download a file.
          // For our sample, we just sleep for 5 seconds.
          long endTime = System.currentTimeMillis() + 5*1000;
          while (System.currentTimeMillis() &lt; endTime) {
              synchronized (this) {
                  try {
                      wait(endTime - System.currentTimeMillis());
                  } catch (Exception e) {
                  }
              }
          }
          // Stop the service using the startId, so that we don't stop
          // the service in the middle of handling another job
          stopSelf(msg.arg1);
      }
  }

  &#64;Override
  public void onCreate() {
    // Start up the thread running the service.  Note that we create a
    // separate thread because the service normally runs in the process's
    // main thread, which we don't want to block.  We also make it
    // background priority so CPU-intensive work will not disrupt our UI.
    HandlerThread thread = new HandlerThread("ServiceStartArguments",
            Process.THREAD_PRIORITY_BACKGROUND);
    thread.start();

    // Get the HandlerThread's Looper and use it for our Handler
    mServiceLooper = thread.getLooper();
    mServiceHandler = new ServiceHandler(mServiceLooper);
  }

  &#64;Override
  public int onStartCommand(Intent intent, int flags, int startId) {
      Toast.makeText(this, "service starting", Toast.LENGTH_SHORT).show();

      // For each start request, send a message to start a job and deliver the
      // start ID so we know which request we're stopping when we finish the job
      Message msg = mServiceHandler.obtainMessage();
      msg.arg1 = startId;
      mServiceHandler.sendMessage(msg);

      // If we get killed, after returning from here, restart
      return START_STICKY;
  }

  &#64;Override
  public IBinder onBind(Intent intent) {
      // We don't provide binding, so return null
      return null;
  }

  &#64;Override
  public void onDestroy() {
    Toast.makeText(this, "service done", Toast.LENGTH_SHORT).show();
  }
}
</pre>

<p> {@link android.app.IntentService}      .</p>

<p>,   {@link android.app.Service#onStartCommand
onStartCommand()}            .
  ,
     (     ).</p>

<p>{@link android.app.Service#onStartCommand onStartCommand()}
    .
    (    {@link
android.app.IntentService}      .     ).
{@link android.app.Service#onStartCommand onStartCommand()}
    .</p>

<dl>
  <dt>{@link android.app.Service#START_NOT_STICKY}</dt>
    <dd>  {@link android.app.Service#onStartCommand
onStartCommand()}      <em> .</em>
    .           ,
          .</dd>
  <dt>{@link android.app.Service#START_STICKY}</dt>
    <dd>  {@link android.app.Service#onStartCommand
onStartCommand()}    ,   {@link
android.app.Service#onStartCommand onStartCommand()}      <em>.</em>
 ,  null  {@link android.app.Service#onStartCommand onStartCommand()}
.        ,
  .
 (   ) .</dd>
  <dt>{@link android.app.Service#START_REDELIVER_INTENT}</dt>
    <dd>  {@link android.app.Service#onStartCommand
onStartCommand()}    ,       {@link
android.app.Service#onStartCommand onStartCommand()}
.     .
   (    ) .</dd>
</dl>
<p>
.</p>


<h3 id="StartingAService"> </h3>

<p>
{@link android.content.Intent}(  ) {@link
android.content.Context#startService startService()}  . Android   {@link
android.app.Service#onStartCommand onStartCommand()}    {@link
android.content.Intent} . ({@link android.app.Service#onStartCommand
onStartCommand()}     .)</p>

<p>     ({@code
HelloService})   {@link android.content.Context#startService
startService()}    .</p>

<pre>
Intent intent = new Intent(this, HelloService.class);
startService(intent);
</pre>

<p>{@link android.content.Context#startService startService()}
Android   {@link android.app.Service#onStartCommand
onStartCommand()}  .      ,   {@link
android.app.Service#onCreate onCreate()} ,  {@link android.app.Service#onStartCommand
onStartCommand()} .</p>

<p>    , {@link
android.content.Context#startService startService()}
  .      ,
   {@link android.app.PendingIntent}
  ({@link android.app.PendingIntent#getBroadcast getBroadcast()} )
{@link android.content.Intent}     .
       .</p>

<p>
{@link android.app.Service#onStartCommand onStartCommand()}      . ,
   ({@link android.app.Service#stopSelf stopSelf()}  {@link
android.content.Context#stopService stopService()} )  .</p>


<h3 id="Stopping"> </h3>

<p>       .  ,
    .
{@link android.app.Service#onStartCommand onStartCommand()}      . ,
 {@link android.app.Service#stopSelf stopSelf()}    ,
   {@link android.content.Context#stopService stopService()}     .</p>

<p> {@link android.app.Service#stopSelf stopSelf()}  {@link
android.content.Context#stopService stopService()}
.</p>

<p>,  {@link
android.app.Service#onStartCommand onStartCommand()}
   .
(        ).
, {@link android.app.Service#stopSelf(int)}
         .  , {@link
android.app.Service#stopSelf(int)}     ID({@link android.app.Service#onStartCommand onStartCommand()}
<code>startId</code>)  .
.    {@link
android.app.Service#stopSelf(int)}          , ID      .</p>

<p class="caution"><strong>:</strong>
       .           .
      . {@link
android.content.Context#stopService stopService()}  .    ,
 {@link
android.app.Service#onStartCommand onStartCommand()}         .</p>

<p>        <a href="#Lifecycle">   </a>   .</p>


<h2 id="CreatingBoundService">  </h2>

<p>          ,  {@link
android.content.Context#bindService bindService()}
(    {@link
android.content.Context#startService startService()}   <em></em>   ).</p>

<p>
   .        (IPC)
     .</p>

<p>   {@link
android.app.Service#onBind onBind()}
{@link android.os.IBinder}   .
{@link android.content.Context#bindService bindService()}    ,
   .
 ,        (
{@link android.app.Service#onStartCommand onStartCommand()}
 <em></em> ).</p>

<p>
       .
 {@link android.os.IBinder}
 {@link android.app.Service#onBind
onBind()}    .  {@link android.os.IBinder}
    .</p>

<p>      .
{@link android.content.Context#unbindService unbindService()}   .
       .</p>

<p>
 .
<a href="{@docRoot}guide/components/bound-services.html"> </a>    .</p>


<h2 id="Notifications">  </h2>

<p>     <a href="{@docRoot}guide/topics/ui/notifiers/toasts.html"> </a>  <a href="{@docRoot}guide/topics/ui/notifiers/notifications.html">  </a>      .</p>

<p>        ,

     (:  ).</p>

<p>,
(:   )
 .     ,
     (:   ).</p>

<p>  <a href="{@docRoot}guide/topics/ui/notifiers/toasts.html"> </a>  <a href="{@docRoot}guide/topics/ui/notifiers/notifications.html">  </a>
  .</p>


<h2 id="Foreground">  </h2>

<p>
      .
      .
" "   ,
       .</p>

<p>
  .
.
          .</p>

<p>    {@link
android.app.Service#startForeground startForeground()}  .      .
             {@link
android.app.Notification}. :</p>

<pre>
Notification notification = new Notification(R.drawable.icon, getText(R.string.ticker_text),
        System.currentTimeMillis());
Intent notificationIntent = new Intent(this, ExampleActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
notification.setLatestEventInfo(this, getText(R.string.notification_title),
        getText(R.string.notification_message), pendingIntent);
startForeground(ONGOING_NOTIFICATION_ID, notification);
</pre>

<p class="caution"><strong>:</strong> {@link
android.app.Service#startForeground startForeground()}   ID 0  .</p>


<p>   {@link
android.app.Service#stopForeground stopForeground()}  .     ,
     .     <em></em>.
 ,
  .</p>

<p>    <a href="{@docRoot}guide/topics/ui/notifiers/notifications.html">
 </a> .</p>


<h2 id="Lifecycle">   </h2>

<p>       . ,
          .
    .</p>

<p>  &mdash;   &mdash;
  .</p>

<ul>
<li>
  <p>     {@link
android.content.Context#startService startService()}  .
   .  {@link
android.app.Service#stopSelf() stopSelf()}   .
. {@link android.content.Context#stopService
stopService()}  .     .</p></li>

<li>
  <p>    () {@link
android.content.Context#bindService bindService()}  .
{@link android.os.IBinder}       .
{@link android.content.Context#unbindService unbindService()}  .
  ,         (
<em></em> ).</p></li>
</ul>

<p>        .  ,
{@link android.content.Context#startService startService()}      .
,     {@link android.content.Context#startService
startService()}     {@link android.content.Intent}  . ,

      ,     . {@link
android.content.Context#bindService bindService()}  .   {@link
android.content.Context#stopService stopService()}  {@link android.app.Service#stopSelf
stopSelf()}         . </p>


<h3 id="LifecycleCallbacks">   </h3>

<p>
           .
      .</p>

<pre>
public class ExampleService extends Service {
    int mStartMode;       // indicates how to behave if the service is killed
    IBinder mBinder;      // interface for clients that bind
    boolean mAllowRebind; // indicates whether onRebind should be used

    &#64;Override
    public void {@link android.app.Service#onCreate onCreate}() {
        // The service is being created
    }
    &#64;Override
    public int {@link android.app.Service#onStartCommand onStartCommand}(Intent intent, int flags, int startId) {
        // The service is starting, due to a call to {@link android.content.Context#startService startService()}
        return <em>mStartMode</em>;
    }
    &#64;Override
    public IBinder {@link android.app.Service#onBind onBind}(Intent intent) {
        // A client is binding to the service with {@link android.content.Context#bindService bindService()}
        return <em>mBinder</em>;
    }
    &#64;Override
    public boolean {@link android.app.Service#onUnbind onUnbind}(Intent intent) {
        // All clients have unbound with {@link android.content.Context#unbindService unbindService()}
        return <em>mAllowRebind</em>;
    }
    &#64;Override
    public void {@link android.app.Service#onRebind onRebind}(Intent intent) {
        // A client is binding to the service with {@link android.content.Context#bindService bindService()},
        // after onUnbind() has already been called
    }
    &#64;Override
    public void {@link android.app.Service#onDestroy onDestroy}() {
        // The service is no longer used and is being destroyed
    }
}
</pre>

<p class="note"><strong>:</strong>
   <em></em> .</p>

<img src="{@docRoot}images/service_lifecycle.png" alt="" />
<p class="img-caption"><strong> 2.</strong>   .
 {@link android.content.Context#startService
startService()}
{@link android.content.Context#bindService bindService()}      .</p>

<p>   ,          . </p>

<ul>
<li> <strong>  </strong> {@link
android.app.Service#onCreate onCreate()}   {@link
android.app.Service#onDestroy}    .
{@link android.app.Service#onCreate onCreate()}     {@link
android.app.Service#onDestroy onDestroy()} .
       {@link
android.app.Service#onCreate onCreate()} ,       {@link
android.app.Service#onDestroy onDestroy()}   .

<p>{@link android.app.Service#onCreate onCreate()} {@link android.app.Service#onDestroy
onDestroy()}     .
{@link android.content.Context#startService startService()}  {@link
android.content.Context#bindService bindService()}    .</p></li>

<li> <strong>  </strong> {@link
android.app.Service#onStartCommand onStartCommand()}  {@link android.app.Service#onBind onBind()}   .
  {@link
android.content.Intent}    {@link android.content.Context#startService
startService()}  {@link android.content.Context#bindService bindService()}    .
<p>
( {@link android.app.Service#onStartCommand
onStartCommand()}     ).   ,    {@link
android.app.Service#onUnbind onUnbind()}  .</p>
</li>
</ul>

<p class="note"><strong>:</strong>
{@link android.app.Service#stopSelf stopSelf()}  {@link
android.content.Context#stopService stopService()}  ,
( {@code onStop()}  ). ,
    .   {@link
android.app.Service#onDestroy onDestroy()} .</p>

<p> 2       .
{@link android.content.Context#startService startService()}
{@link android.content.Context#bindService bindService()}
 ,             .
, {@link android.app.Service#onStartCommand
onStartCommand()}   ( {@link android.content.Context#startService startService()} )
 {@link android.app.Service#onBind onBind()}    (
{@link android.content.Context#bindService bindService()}  ).</p>

<p>       <a href="{@docRoot}guide/components/bound-services.html"> </a>  .   {@link android.app.Service#onRebind onRebind()}
     <a href="{@docRoot}guide/components/bound-services.html#Lifecycle">
  </a>
 .</p>


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