IntentService

我们在用service的时候有一个类IntentService 用法如下:

Creates a default worker thread that executes all intents delivered to onStartCommand() separate from your application's main thread.
Creates a work queue that passes one intent at a time to your onHandleIntent() implementation, so you never have to worry about multi-threading.
Stops the service after all start requests have been handled, so you never have to call stopSelf().
Provides default implementation of onBind() that returns null.
Provides a default implementation of onStartCommand() that sends the intent to the work queue and then to your onHandleIntent() implementation.
总之:a constructor and an implementation of onHandleIntent(). 即实现构造方法和实现onHandleIntent()即可

public class HelloIntentService extends IntentService { 
  
  /**  
   * A constructor is required, and must call the super IntentService(String) 
   * 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. 
   */
  @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() < endTime) { 
          synchronized (this) { 
              try { 
                  wait(endTime - System.currentTimeMillis()); 
              } catch (Exception e) { 
              } 
          } 
      } 
  } 
}

如果我们要重写一些方法such as onCreate(),onStartCommand(), or onDestr(), be sure to call the super implementation

我们必须返回父类的方法 super()

来自为知笔记(Wiz)

posted on 2014-04-28 13:58 转折点人生阅读(142) 评论(0) 收藏举报