Question

我在Android应用程序中实现了手势检测器。一开始它运行良好，但现在根本不起作用。

 override fun onTouchEvent(event: MotionEvent): Boolean {
        this.gestureDetectorCompat?.onTouchEvent(event)
        return super.onTouchEvent(event)
    }

    //Inner class for handling the gestures
    internal inner class CustomGestureListener : GestureDetector.SimpleOnGestureListener() {
        lateinit var SWIPE_MIN_DISTANCE=100
        lateinit var SWIPE_THRESHOLD_VELOCITY=100

        override fun onFling(
                event1: MotionEvent,
                event2: MotionEvent,
                velocityX: Float,
                velocityY: Float
        ): Boolean {
            val X = event1.getX() - event2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY)
            //Swipe from right to left
            if (X >= 100 && X <= 1000) {
                val intent = Intent(this@ChatActivity, SkillsActivity::class.java)
                startActivity(intent)
            }
            return true
        }
    }

Answer 1

我已经用这种方法尝试了。我假设您正在recyclerview中使用它

  val simpleItemTouchCallback = object : ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT) {

            override fun onMove(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder, target: RecyclerView.ViewHolder): Boolean {
                return false
            }

            override fun getSwipeDirs(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder): Int {
                return super.getSwipeDirs(recyclerView, viewHolder)
            }

            override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
                val position = viewHolder.adapterPosition
                if (direction == ItemTouchHelper.LEFT) {

                }

            }

            override fun onChildDraw(c: Canvas, recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder, dX: Float, dY: Float, actionState: Int, isCurrentlyActive: Boolean) {

                val icon: Bitmap
                if (actionState == ItemTouchHelper.ACTION_STATE_SWIPE) {
                    if (dX < 0) {
                        val itemView = viewHolder.itemView
                        val height = itemView.bottom.toFloat() - itemView.top.toFloat()
                        val width = height / 3
                        paint.setColor(Color.parseColor("#0780D3"))
                        val background = RectF(itemView.right.toFloat() + dX, itemView.top.toFloat(), itemView.right.toFloat(), itemView.bottom.toFloat())
                        c.drawRect(background, paint)
                        icon = BitmapFactory.decodeResource(resources, R.drawable.close)
                        val icon_dest = RectF(itemView.right.toFloat() - 2 * width, itemView.top.toFloat() + width, itemView.right.toFloat() - width, itemView.bottom.toFloat() - width)
                        c.drawBitmap(icon, null, icon_dest, paint)
                        super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive)
                    }
                }
            }
        }
        val itemTouchHelper = ItemTouchHelper(simpleItemTouchCallback)
        itemTouchHelper.attachToRecyclerView(rvList)

从左向右滑动时手势检测器不起作用

1 个答案: