public class DroneApp MainActivity extends Application {
    private IARDrone drone;

    public Activity implements JoystickView.RightJoystickListener
        ,JoystickView.LeftJoystickListener, AttitudeListener {

    @Override
    protected void onCreate() {

        drone = new ARDrone("192.168.1.1", null); // null because of missing video support on Android
onCreate(Bundle savedInstanceState) {
        super.onCreate();

onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        JoystickView joystick = findViewById(R.id.left_joystick);
        joystick.setZOrderOnTop(true);
        joystick.getHolder().setFormat(PixelFormat.TRANSLUCENT);
        JoystickView joystick2 = findViewById(R.id.right_joystick);
        joystick2.setZOrderOnTop(true);
        joystick2.getHolder().setFormat(PixelFormat.TRANSLUCENT);


        WifiManager wifi = (WifiManager)getApplicationContext().getSystemService(Context.WIFI_SERVICE);
        final TextView textView = findViewById(R.id.text_init);
        textView.setText("\n Connected to " + wifi.getConnectionInfo().getSSID());

        initialize();

        initButtons();

        Toast.makeText(this, "Touch and hold the buttons", Toast.LENGTH_SHORT).show();

    }
    private void initialize()
    {
        final TextView text = findViewById(R.id.text_init);

        DroneApp app = (DroneApp)getApplication();
        IARDrone drone = app.getARDrone();

        try
        {
            drone.start();
        }
        catch(Exception exc)
        {
            exc.printStackTrace();

            if (drone != null)
                drone.stop();
        }
    }
    public boolean onKeyDown(int keyCode, KeyEvent event)
    {
        if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0)
        {
            new AlertDialog.Builder(this).setMessage("Upon exiting, drone will be disconnected !").setTitle("Exit YADrone ?").setCancelable(false).setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int whichButton)
                {
                    DroneApp app = (DroneApp)getApplication();
                    IARDrone drone = app.getARDrone();
                    drone.stop();

                    finish();
                }
            }).setNeutralButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int whichButton)
                {
                    // User selected Cancel, nothing to do here.
                }
            }).show();

            return true;
        }

        return super.onKeyDown(keyCode, event);
    }


    @Override
    public void onLeftJoystickMoved(float xPercent, float yPercent, int id) {
        DroneApp app = (DroneApp) getApplication();
        IARDrone drone = app.getARDrone();
        if(id == R.id.right_joystick) {
            if ((xPercent > -0.3 && xPercent < 0.3)&& (yPercent < 0.3 && yPercent > -0.3 )){
                drone.getCommandManager().hover();
            }
            if(xPercent > 0.3) {
                drone.getCommandManager().goRight(20);
            }
            if(xPercent < -0.3) {
                drone.getCommandManager().goLeft(20);
            }
            if (yPercent > 0.3) {
                drone.getCommandManager().backward(20);
            }
            if (yPercent < -0.3) {
                drone.getCommandManager().forward(20);
            }
            if(yPercent > 0.3 && xPercent > 0.3) {
                drone.getCommandManager().move(0.2f, 0.2f,0f , 0f );
            }
            if(yPercent < -0.3 && xPercent > 0.3) {
                drone.getCommandManager().move(0.2f, -0.2f,0f , 0f );
            }
            if(yPercent < -0.3 && xPercent < -0.3) {
                drone.getCommandManager().move(-0.2f, -0.2f,0f , 0f );
            }
            if(yPercent > 0.3 && xPercent < -0.3) {
                drone.getCommandManager().move(-0.2f, 0.2f,0f , 0f );
            }

        }
    }

    @Override
    public void onRightJoystickMoved(float xPercent, float yPercent, int id) {
        DroneApp app = (DroneApp) getApplication();
        IARDrone getARDrone()
drone = app.getARDrone();


        if(id == R.id.left_joystick) {
            if ((xPercent > -0.3 && xPercent < 0.3)&& (yPercent < 0.3 && yPercent > -0.3 )){
                drone.getCommandManager().hover();
            }
            if(xPercent > 0.3) {
                drone.getCommandManager().spinRight(50);
            }
            if(xPercent < -0.3) {
                drone.getCommandManager().spinLeft(50);
            }
            if (yPercent > 0.3) {
                drone.getCommandManager().down(50);
            }
            if (yPercent < -0.3) {
                drone.getCommandManager().up(50);
            }

        }
    }


    public void onResume()
    {
        return drone;
super.onResume();
        DroneApp app = (DroneApp) getApplication();
        IARDrone drone = app.getARDrone();

        drone.getNavDataManager().addAttitudeListener(this);
    }

    public void onPause()
    {
        super.onPause();
        DroneApp app = (DroneApp) getApplication();
        IARDrone drone = app.getARDrone();

        drone.getNavDataManager().removeAttitudeListener(this);
    }

    public void attitudeUpdated(final float pitch, final float roll, final float yaw)
    {
        final TextView text = (TextView)findViewById(R.id.text_navdata);

        runOnUiThread(new Runnable() {
            public void run()
            {
                text.setText("Pitch: " + pitch + " Roll: " + roll + " Yaw: " + yaw  );
            }
        });
    }

    @Override
    public void attitudeUpdated(float v, float v1) {

    }

    @Override
    public void windCompensation(float v, float v1) {

    }
}
    private void initButtons() {
        DroneApp app = (DroneApp)getApplication();
        final IARDrone drone = app.getARDrone();

        Button emergency = (Button)findViewById(R.id.emergency);
        emergency.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v)
            {
                drone.reset();
            }
        });

        final Button landing = (Button)findViewById(R.id.take_off);
        landing.setOnClickListener(new View.OnClickListener() {
            boolean isFlying = false;
            public void onClick(View v)
            {
                if (!isFlying)
                {
                    drone.takeOff();
                    drone.hover();
                    landing.setText("LAND");
                }
                else
                {
                    drone.landing();
                    landing.setText("TAKE OFF");
                }
                isFlying = !isFlying;
            }
        });


    }

}