我做了一个非常简单的应用程序，它在一个窗口中显示当前日期 Textview 文本大小为120dp。我想增加和减少一天的日期，每刷右或刷左的手势。
我的代码工作，但它的工作非常缓慢，特别是刷左手势，以减少日期。有时它拒绝工作。
这是我的密码：

Calendar c;
Int day,month,year;
public abstract class OnSwipeTouchListener implements View.OnTouchListener {
        public final GestureDetector gestureDetector;
        public OnSwipeTouchListener (Context ctx){
            gestureDetector = new GestureDetector(ctx, new GestureListener());
        }
        private final class GestureListener extends GestureDetector.SimpleOnGestureListener {
            private static final int SWIPE_THRESHOLD = 100;
            private static final int SWIPE_VELOCITY_THRESHOLD = 100;
            @Override
            public boolean onDown(MotionEvent e) {
                return true;
            }
            @Override
            public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
                boolean result = false;
                try {
                    float diffY = e2.getY() - e1.getY();
                    float diffX = e2.getX() - e1.getX();
                    if (Math.abs(diffX) > Math.abs(diffY)) {
                        if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                            if (diffX > 0) {
                                onSwipeRight();
                            } else {
                                onSwipeLeft();
                            }
                        }
                        result = true;
                    }
                    else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffY > 0) {
                            onSwipeBottom();
                        } else {
                            onSwipeTop();
                        }
                    }
                    result = true;
                } catch (Exception exception) {
                    exception.printStackTrace();
                }
                return result;
            }
        }
        public void onSwipeRight() {
        }
        public void onSwipeLeft() {
        }
        public void onSwipeTop() {
        }
        public void onSwipeBottom() {
        }
    }
textView.setOnTouchListener(new OnSwipeTouchListener(this) {
            public void onSwipeTop() {}
            public void onSwipeRight() {
                c.add(Calendar.DATE, 1);
                day = c.get(Calendar.DAY_OF_MONTH);
                month = c.get(Calendar.MONTH) +1;
                year = c.get(Calendar.YEAR);
                textView.setText(Integer.toString(day));
            }
            public void onSwipeLeft() {
                c.add(Calendar.DATE, -1);
                day = c.get(Calendar.DAY_OF_MONTH);
                month = c.get(Calendar.MONTH) +1;
                year = c.get(Calendar.YEAR);
                textView.setText(Integer.toString(day));
            }
            public void onSwipeBottom() {
                textView.setText("DOWN");
            }
            public boolean onTouch(View v, MotionEvent event) {
                return gestureDetector.onTouchEvent(event);
            }
        });

为什么这段代码的性能这么差？