CTB 4-1

MainActivity.java

    private float boxY;

    // Handler & Timer
    private Handler handler = new Handler();
    private Timer timer = new Timer();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
      
        // ------------
        // --- 省略 ---
        // ------------
      
        boxY = 500.0f;

        timer.schedule(new TimerTask() {
            @Override
            public void run() {
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        changePos();
                    }
                });
            }
        }, 0, 20);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {