FullScreenFragment Code

package com.dexode.fragment;

import android.annotation.TargetApi;
import android.app.Activity;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnSystemUiVisibilityChangeListener;
import android.view.WindowManager;

/**
* @author Dawid Drozd
*         You must manually call onKeyDown and onWindowFocusChanged.
*/
public class FullscreenFragment extends Fragment implements Runnable {

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

setFullscreen();
if (Build.VERSION.SDK_INT > 10) {
registerSystemUiVisibility();
}
}

@Override
public void onDestroy() {
super.onDestroy();
if (Build.VERSION.SDK_INT > 10) {
unregisterSystemUiVisibility();
}
exitFullscreen(getActivity());
}

public static boolean isImmersiveAvailable() {
return android.os.Build.VERSION.SDK_INT >= 19;
}

public void onWindowFocusChanged(boolean hasFocus) {
if (hasFocus) {
_handler.removeCallbacks(this);
_handler.postDelayed(this, 300);
} else {
_handler.removeCallbacks(this);
}
}

public void onKeyDown(int keyCode) {
if ((keyCode == KeyEvent.KEYCODE_VOLUME_DOWN || keyCode == KeyEvent.KEYCODE_VOLUME_UP)) {
_handler.removeCallbacks(this);
_handler.postDelayed(this, 500);
}
}

@Override
public void onStop() {
_handler.removeCallbacks(this);
super.onStop();
}

@Override
public void run() {
setFullscreen();
}

public void setFullscreen() {
setFullscreen(getActivity());
}

public void setFullscreen(Activity activity) {
if (Build.VERSION.SDK_INT > 10) {
int flags = View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN | View.SYSTEM_UI_FLAG_FULLSCREEN;

if (isImmersiveAvailable()) {
flags |= View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION |
View.SYSTEM_UI_FLAG_HIDE_NAVIGATION | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
}

activity.getWindow().getDecorView().setSystemUiVisibility(flags);
} else {
activity.getWindow()
.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
}
}

public void exitFullscreen(Activity activity) {
if (Build.VERSION.SDK_INT > 10) {
activity.getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
} else {
activity.getWindow()
.setFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
}
}

private Handler _handler = new Handler();

@TargetApi(Build.VERSION_CODES.HONEYCOMB)
private void registerSystemUiVisibility() {
final View decorView = getActivity().getWindow().getDecorView();
decorView.setOnSystemUiVisibilityChangeListener(new OnSystemUiVisibilityChangeListener() {

@Override
public void onSystemUiVisibilityChange(int visibility) {
if ((visibility & View.SYSTEM_UI_FLAG_FULLSCREEN) == 0) {
setFullscreen();
}
}
});
}

@TargetApi(Build.VERSION_CODES.HONEYCOMB)
private void unregisterSystemUiVisibility() {
final View decorView = getActivity().getWindow().getDecorView();
decorView.setOnSystemUiVisibilityChangeListener(null);
}
}