Android Developer Documentation

• MotionEvent

Exercise

In this exercise you are going to implement touchStart().

1. At the class level, add variables to cache the latest x and y values. After the user stops moving and lifts their touch, these are the starting point for the next path (the next segment of the line to draw).

private var currentX = 0f
private var currentY = 0f

2. Implement the touchStart() method as follows. Reset the path, move to the x-y coordinates of the touch event (motionTouchEventX and motionTouchEventY) and assign currentX and currentY to that value.

private fun touchStart() {
   path.reset()
   path.moveTo(motionTouchEventX, motionTouchEventY)
   currentX = motionTouchEventX
   currentY = motionTouchEventY
}