How to add a gesture detector to a view in Android

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I was struggling with adding a gesture detector to a subview in my project. Do I override the parent's onTouchEvent or the child's onTouchEvent? Do I make an OnTouchListener and add the gesture detector there? The documentation shows an example for how to add a gesture detector to the activity itself but it is not clear how to add it to a view. The same process could be used if subclassing a view (example here), but I want to add the gesture without subclassing anything.

This is the closest other question I could find but it is specific to a fling gesture on an ImageView, not to the general case of any View. Also there is some disagreement in those answers about when to return true or false.

To help myself understand how it works, I made a stand alone project. My answer is below.

gesturedetector touch-event android
2 Answers

short version in kotlin to detect double tap only for a view:

val gestureDetector = GestureDetector(activity, object : GestureDetector.SimpleOnGestureListener() {
    override fun onDoubleTap(e: MotionEvent?): Boolean {
        Log.d("myApp", "double tap")
        return true
    }
})
myView.setOnTouchListener { _, event -> gestureDetector.onTouchEvent(event) }

and don't forget to make myView clickable

user_12359100
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