Question

As far as I know, it is possible to hide the notification/title bar, once the
activity is visible (has content) , But… maybe I’m wrong?

Is there any way to hide it after the activity is visible?

Answer 1

You can define the activity to use a theme that eliminates the notification/title bar. For instance, you can add this as an attribute to your <activity ... > tag in AndroidManifest.xml:

android:theme="@android:style/Theme.NoTitleBar.Fullscreen"

The presence of a title cannot be changed once you have called setContentView(). The only way to hide the title bar after your activity has started is to restart the activity with a modified intent. Do something like this:

Intent intent = getIntent();
overridePendingTransition(0, 0);
intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
intent.putExtra("NoTitle", true);
finish();

overridePendingTransition(0, 0);
startActivity(intent);

Then in onCreate() test whether the “NoTitle” extra is present in the intent and make the appropriate call to requestWindowFeature() before calling setContentView().