У меня работает ..
@Override
public void onAttachedToWindow() {
super.onAttachedToWindow();
this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);
}
Тогда
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(keyCode == KeyEvent.KEYCODE_HOME){
// Your code here.
return true;
}
return false;
}