Drag and scale | Android Developers （MotionEventCompat を使ってたりちょっと古い）を参考に変えたもの
class SimpleDragView : FrameLayout {
constructor(context: Context) : super(context)
constructor(context: Context, attrs: AttributeSet?) : super(context, attrs)
constructor(context: Context, attrs: AttributeSet?, defStyleAttr: Int) : super(
context,
attrs,
defStyleAttr
)
private var activePointerId = INVALID_POINTER_ID
private var lastTouchX = 0f
private var lastTouchY = 0f
private val targetView: View
init {
val size = (100 * resources.displayMetrics.density).toInt()
targetView = View(context).apply {
layoutParams = LayoutParams(size, size)
setBackgroundColor(Color.RED)
}
addView(targetView)
}
override fun onTouchEvent(ev: MotionEvent): Boolean {
when (ev.actionMasked) {
MotionEvent.ACTION_DOWN -> {
val pointerIndex = ev.actionIndex
val x = ev.getX(pointerIndex)
val y = ev.getY(pointerIndex)
if (!(x.toInt() in 0..width && y.toInt() in 0..height)) {
return false
}
val left = targetView.translationX
val right = left + targetView.width
val top = targetView.translationY
val bottom = top + targetView.height
if (!(x in left..right && y in top..bottom)) {
return false
}
lastTouchX = x
lastTouchY = y
activePointerId = ev.getPointerId(0)
}
MotionEvent.ACTION_MOVE -> {
if (activePointerId == INVALID_POINTER_ID) {
return false
}
val pointerIndex = ev.findPointerIndex(activePointerId)
val x = ev.getX(pointerIndex)
val y = ev.getY(pointerIndex)
if (!(x.toInt() in 0..width && y.toInt() in 0..height)) {
return false
}
val diffX = x - lastTouchX
val diffY = y - lastTouchY
targetView.translationX += diffX
targetView.translationY += diffY
lastTouchX = x
lastTouchY = y
}
MotionEvent.ACTION_UP,
MotionEvent.ACTION_CANCEL -> {
activePointerId = INVALID_POINTER_ID
}
MotionEvent.ACTION_POINTER_UP -> {
if (activePointerId == INVALID_POINTER_ID) {
return false
}
val pointerIndex = ev.actionIndex
if (ev.getPointerId(pointerIndex) != activePointerId) {
return false
}
val newPointerIndex = if (pointerIndex == 0) 1 else 0
val x = ev.getX(newPointerIndex)
val y = ev.getY(newPointerIndex)
if (!(x.toInt() in 0..width && y.toInt() in 0..height)) {
activePointerId = INVALID_POINTER_ID
return false
}
lastTouchX = x
lastTouchY = y
activePointerId = ev.getPointerId(newPointerIndex)
}
}
return true
}
}
0 件のコメント:
コメントを投稿