Is it possible to permanently remove the Navigation Bar on an activity? I want to remove the bar with the buttons that appear at the button of the screen on a tablet, not the Action Bar. Here.
I know it is not recommended to do that, I did not make this decision, but I need to do it. On my layout, there is another button to leave the activity. The rest of my app can have and does have the Navigation Bar.
I found this code and adapted it a little bit. The problem is that even when I hide the Navigation Bar, there is a black space left behind. I guess the system calculates the screen size having into account the navigation bar?
public static class Content extends ImageView implements View.OnSystemUiVisibilityChangeListener, View.OnClickListener, ActionBar.OnMenuVisibilityListener {
Activity mActivity;
TextView mTitleView;
Button mPlayButton;
SeekBar mSeekView;
boolean mAddedMenuListener;
boolean mMenusOpen;
boolean mPaused;
boolean mNavVisible;
int mLastSystemUiVis;
Runnable mNavHider = new Runnable() {
@Override public void run() {
setNavVisibility(false);
}
};
public Content(Context context, AttributeSet attrs) {
super(context, attrs);
setOnSystemUiVisibilityChangeListener(this);
setOnClickListener(this);
}
public void init(Activity activity, TextView title, Button playButton,
SeekBar seek) {
// This called by the containing activity to supply the surrounding
// state of the video player that it will interact with.
mActivity = activity;
mTitleView = title;
mPlayButton = playButton;
mSeekView = seek;
mPlayButton.setOnClickListener(this);
setPlayPaused(true);
}
@Override protected void onAttachedToWindow() {
super.onAttachedToWindow();
if (mActivity != null) {
mAddedMenuListener = true;
mActivity.getActionBar().addOnMenuVisibilityListener(this);
}
}
@Override protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
if (mAddedMenuListener) {
mActivity.getActionBar().removeOnMenuVisibilityListener(this);
}
}
@Override public void onSystemUiVisibilityChange(int visibility) {
// Detect when we go out of nav-hidden mode, to clear our state
// back to having the full UI chrome up. Only do this when
// the state is changing and nav is no longer hidden.
int diff = mLastSystemUiVis ^ visibility;
mLastSystemUiVis = visibility;
if ((diff&SYSTEM_UI_FLAG_HIDE_NAVIGATION) != 0
&& (visibility&SYSTEM_UI_FLAG_HIDE_NAVIGATION) == 0) {
setNavVisibility(true);
}
}
@Override protected void onWindowVisibilityChanged(int visibility) {
super.onWindowVisibilityChanged(visibility);
// When we become visible or invisible, play is paused.
setPlayPaused(true);
}
@Override public void onClick(View v) {
if (v == mPlayButton) {
// Clicking on the play/pause button toggles its state.
setPlayPaused(!mPaused);
} else {
// Clicking elsewhere makes the navigation visible.
setNavVisibility(true);
}
}
@Override public void onMenuVisibilityChanged(boolean isVisible) {
mMenusOpen = isVisible;
setNavVisibility(true);
}
void setPlayPaused(boolean paused) {
mPaused = paused;
mPlayButton.setText(paused ? R.string.play : R.string.pause);
setKeepScreenOn(!paused);
setNavVisibility(true);
}
void setNavVisibility(boolean visible) {
int newVis = SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
| SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
| SYSTEM_UI_FLAG_LAYOUT_STABLE;
if (!visible) {
newVis |= SYSTEM_UI_FLAG_LOW_PROFILE | SYSTEM_UI_FLAG_FULLSCREEN
| SYSTEM_UI_FLAG_HIDE_NAVIGATION;
}
// If we are now visible, schedule a timer for us to go invisible.
if (visible) {
Handler h = getHandler();
if (h != null) {
h.removeCallbacks(mNavHider);
if (!mMenusOpen && !mPaused) {
// If the menus are open or play is paused, we will not auto-hide.
h.postDelayed(mNavHider, 1500);
}
}
}
// Set the new desired visibility.
setSystemUiVisibility(newVis);
mTitleView.setVisibility(visible ? VISIBLE : INVISIBLE);
mPlayButton.setVisibility(visible ? VISIBLE : INVISIBLE);
mSeekView.setVisibility(visible ? VISIBLE : INVISIBLE);
}
}
There is a solution starting with KitKat (4.4.2), called Immersive Mode: https://developer.android.com/training/system-ui/immersive.html
Basically, you should add this code to your onResume() method:
View decorView = getWindow().getDecorView();
decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
| View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_FULLSCREEN
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);