Android: show/hide status bar/power bar

Do you have the fullscreen theme set in the manifest?

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

I don’t think you’ll be able to go fullscreen without this.

I would use the following to add and remove the fullscreen flag:

// Hide status bar
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
// Show status bar
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);