如何從服務轉到主屏幕？

我有這個MainService，它一旦啓動，就關閉屏幕並且只有在定時器結束後纔打開它（此外，在定時器結束之後，所述服務也停止）。如何從服務轉到主屏幕？

我的問題是：在屏幕關閉之前，應用程序是否還可以進入背景？進入後臺我的意思是主屏幕出現。

MainActivity：

public class MainActivity extends AppCompatActivity { 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    final Button startApp = (Button) findViewById(R.id.startApp); 
    final EditText timer = (EditText) findViewById(R.id.insertTimer); 

    assert startApp != null; 
    startApp.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      Toast.makeText(MainActivity.this, "Countdown, Started", Toast.LENGTH_SHORT).show(); 

      Intent intent = new Intent(MainActivity.this, MainService.class); 

      assert timer != null; 
      intent.putExtra("timer", timer.getText().toString()); 

      Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_OFF_TIMEOUT, 1000); 

      registerReceiver(broadcastReceiver, new IntentFilter(MainService.BROADCAST_ACTION)); 

      startService(intent); 
     } 
    }); 
} 

private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() { 
    @Override 
    public void onReceive(Context context, Intent intent) { 
     updateUI(intent); 
    } 
}; 

private void updateUI(Intent intent) { 
    String counter = intent.getStringExtra("counter"); 
    TextView txtCounter = (TextView) findViewById(R.id.txtCounter); 
    assert txtCounter != null; 
    txtCounter.setText(counter); 
}

MainService：

public class MainService extends Service { 

public static final String BROADCAST_ACTION = "com.example.vladpintea.friendsbeforecents.displayevent"; 
private final Handler handler = new Handler(); 
int counterr = 0; 
Intent intentt; 

String usedTimer; 
long interval; 

//TimerTask that will cause the run() runnable to happen. 
TimerTask myTask = new TimerTask() { 
    public void run() { 
     stopSelf(); 
    } 
}; 
//Timer that will make the runnable run. 
Timer myTimer = new Timer(); 

@Override 
public void onCreate() { 
    intentt = new Intent(BROADCAST_ACTION); 

    registerReceiver(counter, new IntentFilter(Intent.ACTION_SCREEN_ON)); 

    Toast.makeText(MainService.this, "Service, Created", Toast.LENGTH_SHORT).show(); 
} 

private BroadcastReceiver counter = new BroadcastReceiver() { 
    @Override 
    public void onReceive(Context context, Intent intent) { 
     Toast.makeText(MainService.this, "Whoops! You've Lost.", Toast.LENGTH_SHORT).show(); 
     Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_OFF_TIMEOUT, 30000); 
    } 
}; 

@Override 
public int onStartCommand(Intent intent, int flags, int startId) { 
    Toast.makeText(MainService.this, "Service, Started", Toast.LENGTH_SHORT).show(); 

    usedTimer = intent.getStringExtra("timer"); 
    try { 
     interval = Long.parseLong(usedTimer); 
    } catch (NumberFormatException ignored) {} 

    myTimer.schedule(myTask, interval); 

    handler.removeCallbacks(sendUpdatesToUI); 
    handler.postDelayed(sendUpdatesToUI, 1000); 

    return super.onStartCommand(intent, flags, startId); 
} 

private Runnable sendUpdatesToUI = new Runnable() { 
    public void run() { 
     handler.postDelayed(this, 1000); 
    } 
}; 

public void DisplayLoggingInfoPlus() { 
    intentt.putExtra("counter", String.valueOf(++counterr)); 
    sendBroadcast(intentt); 
} 

@Override 
public void onDestroy() { 
    DisplayLoggingInfoPlus(); 

    PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE); 
    PowerManager.WakeLock wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK 
      | PowerManager.ACQUIRE_CAUSES_WAKEUP 
      | PowerManager.ON_AFTER_RELEASE, "MyWakeLock"); 
    wakeLock.acquire(); 

    Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_OFF_TIMEOUT, 30000); 
} 

@Override 
public IBinder onBind(Intent intent) { 
    return null; 
}

來源

2016-08-15 Vlad Pintea

是否[此]（http://stackoverflow.com/questions/3724509/going-to-home-screen-programmatically）覆蓋它？ – Vucko

不幸的是，沒有，因爲我試圖從服務中轉到主屏幕，而不是通過活動中的按鈕。 –

這沒關係。爲什麼你不能用計時器或觸發屏幕鎖定的東西來觸發這一點？ – Vucko