kotlin swipe listener
open class OnSwipeTouchListener : View.OnTouchListener { private val gestureDetector = GestureDetector(GestureListener()) fun onTouch(event: MotionEvent): Boolean { return gestureDetector.onTouchEvent(event) } private inner class GestureListener : GestureDetector.SimpleOnGestureListener() { private val SWIPE_THRESHOLD = 100 private val SWIPE_VELOCITY_THRESHOLD = 100 override fun onDown(e: MotionEvent): Boolean { return true } override fun onSingleTapConfirmed(e: MotionEvent): Boolean { onTouch(e) return true } override fun onFling(e1: MotionEvent, e2: MotionEvent, velocityX: Float, velocityY: Float): Boolean { val result = false try { val diffY = e2.y - e1.y val diffX = e2.x - e1.x 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() } } } else { // onTouch(e); } } catch (exception: Exception) { exception.printStackTrace() } return result } } override fun onTouch(v: View, event: MotionEvent): Boolean { return gestureDetector.onTouchEvent(event) } open fun onSwipeRight() {} open fun onSwipeLeft() {} open fun onSwipeTop() {} open fun onSwipeBottom() {} }
