Android Textview 慢，甚至根本不工作

Question

I made a very simple app which displays current date in day of month inside a Textview at 120dp text size. I want to increment and decrement the date by one day every swipe right or swipe left gesture.

My code worked but it worked very slowly especially the swipe left gesture to decrement the date. Sometimes it refused to work.

Here is my code:

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);
            }
        }); 

Why is the performance of this code so poor?

Answer 1

Use RecyclerView with horizontal orientation instead TextView...may be it will give much smooth & great performance then applying Gesture tracker on TextView..

Answer 2

Thank you guys. I managed to solve this issue myself, just set listener to the layout and everything works like a charm.