How to catch double tap events in Android using OnTouchListener

Question

I am trying to catch double-tap events using OnTouchListener. I figure I would set a long for motionEvent.ACTION_DOWN, and a different long for a second motionEvent.ACTION_D

Answer 1

Another approach that supports both single click and double clicks using Kotlin Coroutine:

var lastDown = 0L
var clickCount = 0

view.setOnTouchListener {v, event ->
    when (event.action) {
        MotionEvent.ACTION_DOWN -> {
            val downTime = System.currentTimeMillis()
            clickCount++
            if (lastDown > 0 && downTime - lastDown < 300 && clickCount == 2) {
                //double clicks happens here
                clickCount = 0
            }
            lastDown = downTime
        }
        MotionEvent.ACTION_UP -> {
            CoroutineScope(Dispatchers.IO).launch {
                //in case clickCount goes beyond than 1, here set it to 1
                val upTime = System.currentTimeMillis()
                if (upTime - lastDown <= 300 && clickCount > 0) {
                    clickCount = 1
                }
                delay(300)
                if (System.currentTimeMillis() - lastDown > 300 && clickCount == 1) {
                    withContext(Dispatchers.Main) {
                        //single click happens here
                    }
                    clickCount = 0
                }
            }
        }
    }
    true
}