当设备被锁定时显示AlertDialog

Question

我必须开发一个应用程序，在2小时内每10分钟显示一个AlertDialog [Alarm] [从用户单击StartButton时开始]，实际上我输入此代码它显示alertDialog但当我测试了我的手机在AlertDialog当移动锁定不会出现，不过，我还是有一些问题，

这是我的代码： -

//Activity 

public class AndroidAlarmService extends Activity { 

private PendingIntent pendingIntent; 


/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 
    Button buttonStart = (Button)findViewById(R.id.startalarm); 
    Button buttonCancel = (Button)findViewById(R.id.cancelalarm); 

    buttonStart.setOnClickListener(new View.OnClickListener() { 

     public void onClick(View v) { 
      // TODO Auto-generated method stub 
     Intent myIntent = new Intent(AndroidAlarmService.this, BroadCastReceiverFor.class); 
      pendingIntent = PendingIntent.getBroadcast(AndroidAlarmService.this, 234324243, myIntent, 0); 

      Calendar calendar = Calendar.getInstance(); 
      calendar.setTimeInMillis(System.currentTimeMillis()); 
      calendar.add(Calendar.MINUTE, 10);  

      AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE); 
      alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent); 



       Toast.makeText(AndroidAlarmService.this, "Start Alarm", Toast.LENGTH_LONG).show(); 
     } 
    }); 

    buttonCancel.setOnClickListener(new View.OnClickListener() { 

     public void onClick(View v) { 
      // TODO Auto-generated method stub 
       AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE); 
       alarmManager.cancel(pendingIntent); 

         // Tell the user about what we did. 
         Toast.makeText(AndroidAlarmService.this, "Cancel!", Toast.LENGTH_LONG).show(); 
     } 
    }); 

} 

} 
//BroadcastReceiver 


public class BroadCastReceiverFor extends BroadcastReceiver { 

    @Override 
    public void onReceive(Context context, Intent intent) { 

     Intent service = new Intent(context, MyAlarmService.class); 
     context.startService(service); 

    } 
} 

// Service 

public class MyAlarmService extends Service { 

    @Override  

public void onCreate() {  
     // TODO Auto-generated method stub  
     Toast.makeText(this, "MyAlarmService.onCreate()", Toast.LENGTH_LONG) 
     .show();  }  
    @Override 
    public IBinder onBind(Intent intent) { 
      // TODO Auto-generated method stub 
      Toast.makeText(this, "MyAlarmService.onBind()", Toast.LENGTH_LONG) 
      .show();   return null; 
      } 
     @Override 
     public void onDestroy() { 
      // TODO Auto-generated method stub 
      super.onDestroy(); 
      Toast.makeText(this, "MyAlarmService.onDestroy()", Toast.LENGTH_LONG) 
      .show();  } 
     @Override 
     public void onStart(Intent intent, int startId) { 
      // TODO Auto-generated method stub 
      super.onStart(intent, startId); 

      Toast.makeText(this, "MyAlarmService.onStart()", Toast.LENGTH_LONG).show(); 
      Intent dialog = new Intent(this, ShowingDialog.class); 
      dialog.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
      startActivity(dialog); 

      }  
     @Override  
      public boolean onUnbind(Intent intent) 
      {   // TODO Auto-generated method stub  
       Toast.makeText(this, "MyAlarmService.onUnbind()", Toast.LENGTH_LONG)  
       .show();   return super.onUnbind(intent);  } 



} 


// Another Activity to show the AlertDialog 


public class ShowingDialog extends Activity { 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     // TODO Auto-generated method stub 
     super.onCreate(savedInstanceState); 
     //For Notification 

    final AlertDialog alertDialog = new AlertDialog.Builder(this).create(); 

    //For Notification 
      alertDialog.setTitle("Conformation"); 
      alertDialog.setMessage("Are you sure you want to Do that?"); 


        alertDialog.setButton("Yes", new DialogInterface.OnClickListener() { 
         public void onClick(DialogInterface dialog, int which) { 


         } 
        }); 



        alertDialog.setIcon(android.R.drawable.ic_dialog_alert); 
        alertDialog.show(); 

    } 




} 

// Manifest 

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
     package="com.exercise.AndroidAlarmService" 
     android:versionCode="1" 
     android:versionName="1.0"> 
    <uses-sdk android:minSdkVersion="4" /> 

    <application android:icon="@drawable/icon" android:label="@string/app_name"> 
     <activity android:name=".AndroidAlarmService" 
        android:label="@string/app_name"> 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 
       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 


    <activity 
    android:name=".ShowingDialog" 
    android:theme="@android:style/Theme.Dialog"/> 


     <service android:name=".MyAlarmService" /> 
     <receiver android:name="BroadCastReceiverFor"></receiver> 

    </application> 
</manifest> 

我的问题是：

1-即使设备被锁定，我如何才能使此警报对话框出现？ 2-如何在20分钟后再次出现对话框？

感谢adavance ..

Answer 1

为了让您的活动，即使推出，如果设备是睡着了，你就需要acquire a WakeLock

This page has a nice overview of how it is done.

为了让您的警报再次触发只覆盖AlertDialog上的按钮创建一个新的PendingIntent，并使用AlarmManager以与第一次相同的方式进行设置。