requestFeature() must be called before adding the content

Question

I want to create an android application to trigger the alarm. I have a button called btnStart. When the user click the button, in 3 second, it should go to AlarmReceiverActivity.java and start play the sound.

the btnStart onclick method look like

btnStart.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            int i = 3;
            Intent intent = new Intent (MapPage.this, AlarmReceiverActivity.class);
                PendingIntent pending =
                        PendingIntent.getActivity(MapPage.this, 2, intent, 
                                            PendingIntent.FLAG_CANCEL_CURRENT);

            AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
                            am.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()+(i * 1000), pending);

            if (toast != null){
                toast.cancel();
            }

            toast = Toast.makeText(getApplicationContext(), "Alarm for activity is set in : "+ i +" second", toast.LENGTH_SHORT);
            toast.show();                       
            }
        });

and the AlarmReceiverActivity.java look like this

public class AlarmReceiverActivity extends Activity{
private MediaPlayer mMediaPlayer;
private PowerManager.WakeLock mWakeLock;

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

    PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
    mWakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, "My Wake Log");
    mWakeLock.acquire();
    this.requestWindowFeature(Window.FEATURE_NO_TITLE);
    this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN |
            WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
            WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON,
            WindowManager.LayoutParams.FLAG_FULLSCREEN |
            WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
            WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);

    Button stopAlarm = (Button) findViewById(R.id.stopAlarm);
    stopAlarm.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            mMediaPlayer.stop();
            finish();
        }
    });
    playSound (this, getAlarmUri());
}

to make this short question short, there are some method that I not state above. When I click the button, I got and error. It say that

java.lang.RunTimeException: Unable to start activity ComponentInfo{com.example.splashscreen/com.example.splashscreen.AlarmReceiverActivity}: android.util.AndroidRuntimeException: requestFeature() must be called before adding content

Any idea on how to solve this problem ? Thank you in advance

Answer 1

Chnage the order like this..

this.requestWindowFeature(Window.FEATURE_NO_TITLE);
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN |
            WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
            WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON,
            WindowManager.LayoutParams.FLAG_FULLSCREEN |
            WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
            WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
super.onCreate(savedInstanceState);
setContentView(R.layout.alarm);

Answer 2

Put this:

this.requestWindowFeature(Window.FEATURE_NO_TITLE);

before this:

setContentView(R.layout.alarm);

From the docs on requestWindowFeature (emphasis added):

Enable extended screen features. This must be called before setContentView(). May be called as many times as desired as long as it is before setContentView(). If not called, no extended features will be available. You can not turn off a feature once it is requested. You canot use other title features with FEATURE_CUSTOM_TITLE.