Android周學習Step By Step（9）–Intent之廣播（完）

通過broadcast Intent機制可以將一個Intent發送給任何對這個Intent感興趣的BroadcastReceiver。

 

通過new Intent（ACTION_1）建立Action為ACTION_1的Intent。

通過sendBroadcast（intent）將這個intent進行廣播。代碼如下

ActivityMain代碼：

   1:  package com.eoeandroid.broadcastReceiver;

   2:  import android.app.NotificationManager;

   3:  import android.content.BroadcastReceiver;

   4:  import android.content.Context;

   5:  import android.content.Intent;

   6:  public class EoeAndroidReceiver2 extends BroadcastReceiver {

   7:      Context context;

   8:      @Override

   9:      public void onReceive(Context context, Intent intent) {

  10:          // TODO Auto-generated method stub

  11:          this.context = context;

  12:          DeleteNotification();

  13:      }

  14:      private void DeleteNotification() {        

  15:          NotificationManager notificationManager = (NotificationManager) context

  16:                  .getSystemService(android.content.Context.NOTIFICATION_SERVICE);

  17:          notificationManager.cancel(EoeAndroidReceiver1.NOTIFICATION_ID);

  18:      

  19:      }

  20:  }

當單擊MENU的第一項後，程式執行到EoeAndroidReceiver1，通過OnRecievie方法將一個Notification顯示在了狀態列中。其中showNotification（）負責顯示一個Notification。代碼如下：

EoeAndroidReceiver1代碼

   1:  package com.eoeandroid.broadcastReceiver;

   2:  import android.app.Notification;

   3:  import android.app.NotificationManager;

   4:  import android.app.PendingIntent;

   5:  import android.content.BroadcastReceiver;

   6:  import android.content.Context;

   7:  import android.content.Intent;

   8:  public class EoeAndroidReceiver1 extends BroadcastReceiver {

   9:      Context context;

  10:      public static int NOTIFICATION_ID = 21321;

  11:      @Override

  12:      public void onReceive(Context context, Intent intent) {

  13:          this.context = context;

  14:          showNotification();

  15:      }

  16:      private void showNotification() {

  17:          NotificationManager notificationManager = (NotificationManager) context

  18:                  .getSystemService(android.content.Context.NOTIFICATION_SERVICE);

  19:          Notification notification = new Notification(R.drawable.icon,

  20:                  "在EoeAndroidReceiver1中", System.currentTimeMillis());

  21:          PendingIntent contentIntent = PendingIntent.getActivity(context, 0,

  22:                  new Intent(context, ActivityMain.class), 0);

  23:          notification.setLatestEventInfo(context, "在EoeAndroidReceiver1中", null,

  24:                  contentIntent);

  25:          notificationManager.notify(NOTIFICATION_ID, notification);

  26:      }

  27:  }

單擊第二個按鈕後程式開始廣播，這個廣播被EoeAndroidReceiver2截獲然後開始執行EoeAndroidReceiver2裡的OnReceive方法，其中DeleteNotification（）方法負責將剛才產生的Notification從狀態列中刪除。代碼如下：

EoeAndroidReceiver2代碼

   1:  package com.eoeandroid.broadcastReceiver;

   2:  import android.app.NotificationManager;

   3:  import android.content.BroadcastReceiver;

   4:  import android.content.Context;

   5:  import android.content.Intent;

   6:  public class EoeAndroidReceiver2 extends BroadcastReceiver {

   7:      Context context;

   8:      @Override

   9:      public void onReceive(Context context, Intent intent) {

  10:          // TODO Auto-generated method stub

  11:          this.context = context;

  12:          DeleteNotification();

  13:      }

  14:      private void DeleteNotification() {        

  15:          NotificationManager notificationManager = (NotificationManager) context

  16:                  .getSystemService(android.content.Context.NOTIFICATION_SERVICE);

  17:          notificationManager.cancel(EoeAndroidReceiver1.NOTIFICATION_ID);    

  18:      }

  19:  }

Android學習到此告一段落，經過一周的學習（嚴格的說學習的時間外加寫論文的時間是一周，總結、寫部落格的時間遠遠大於一周）只能對Android有個大致的瞭解，還有很多方面由於時間的原因不能夠深入學習，甚至很多都沒有接觸到，以後有時間再學習吧。

Android，有緣我們還會再見！