MainActivity.java

MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.view.GestureDetectorCompat;

import android.os.Bundle;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;

public class MainActivity extends AppCompatActivity {

    private GestureDetectorCompat mGestureDetector;

    private class GestureListener extends GestureDetector.SimpleOnGestureListener {
        @Override
        public boolean onDown(MotionEvent event) {
            return true;
        }

        @Override
        public boolean onFling(MotionEvent event1, MotionEvent event2,
                        float velocityX, float velocityY) {
            return true;
        }

        @Override
        public boolean onSingleTapUp(MotionEvent e) {
            if (getSupportActionBar() != null && getSupportActionBar().isShowing()) {
                hideSystemUi();
            } else {
                showSystemUI();
            }
            return true;
        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mGestureDetector = new GestureDetectorCompat(this, new GestureListener());
        hideSystemUi();
    }

    private void hideSystemUi() {
        getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_IMMERSIVE |
                View.SYSTEM_UI_FLAG_FULLSCREEN |
                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);
    }

    private void showSystemUI() {
        getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE |
                        View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION |
                        View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        mGestureDetector.onTouchEvent(event);
        return super.onTouchEvent(event);
    }
}