android - requestWindowFeature(Window.FEATURE_NO_TITLE) exception

Question

I am setting a specific activity full screen when the use hits a START button.

In this case the showStopButton() is called .

It's running fine. But if I insert

 requestWindowFeature(Window.FEATURE_NO_TITLE); 

then it crashes , stating that it should be call before adding content.

How should I handle it to set NO_TITLE w the FULL_SCREEN ??

    private void showStopButton(){

    // requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
    getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
    getWindow().findViewById(android.R.id.content).requestLayout();

    // handle element visibility
((Button)findViewById(R.id.stopButton)).setEnabled(false);
    ((Button)findViewById(R.id.startButton)).setVisibility(View.GONE);
    ((Button)findViewById(R.id.stopButton)).setVisibility(View.VISIBLE);
    ((SeekBar)findViewById(R.id.seekBar1)).setVisibility(View.VISIBLE);
    ((Button)findViewById(R.id.resetButton)).setVisibility(View.GONE);
    ((Button)findViewById(R.id.saveButton)).setVisibility(View.GONE);
}

I have the reverse process when the START button is redisplayed , and it's running back fine In this case I remove the fullscreen mode

     private void showStartButton(){

        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
        getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().findViewById(android.R.id.content).requestLayout();
        ....
    }

Answer 1

So:

@Override
protected void onCreate(
    final Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);

    // Make this activity, full screen
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
        WindowManager.LayoutParams.FLAG_FULLSCREEN);

    // Hide the Title bar of this activity screen
    getWindow().requestFeature(Window.FEATURE_NO_TITLE);

    setContentView(R.layout.main);

    // MORE INIT STUFF HERE...
    //img = (ImageView) findViewById(R.id.imgRandom);
    //btnRandom = (Button) findViewById(R.id.btnRandom);
}

Answer 2

it's so simple ... I just need to hide the ActionBar... then show it when back to standard screen...

   private void showStopButton(){
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
        ActionBar actionBar = getActionBar();
        actionBar.hide();
        getWindow().findViewById(android.R.id.content).requestLayout();

Answer 3

Use -public class MainActivity extends Activity- instead of -public class MainActivity extends ActionBarActivity-

Answer 4

Try this one......

public class MainActivity extends Activity {

    Context context;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        context = this;

        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.activity_main);
    }
}

Answer 5

Add this.

requestWindowFeature(Window.FEATURE_NO_TITLE);

before

 super.onCreate(savedInstanceState);
 setContentView(R.layout.your activity);

Answer 6

It could be like this :

public class MainActivity extends AppCompatActivity {
   ...
    private final Handler handler = new Handler();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getSupportActionBar().hide(); 
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        setContentView(R.layout.activity_main);

I used the above codes in the example of police car lights and siren.When the application is started, the light animation starts automatically and the siren sounds in the background.

Source : Android police lights & siren