【Android】手写笔适配

以下代码分别用于检测

• 是否为手写笔事件
• 是否为橡皮擦事件
• 是否为手写笔主按钮
• 是否为手写笔辅按钮

override fun dispatchTouchEvent(event: MotionEvent): Boolean {
  val isStylus = event.getToolType(event.actionIndex) == MotionEvent.TOOL_TYPE_STYLUS
  val isEraser = event.getToolType(event.actionIndex) == MotionEvent.TOOL_TYPE_ERASER
  val isStylusPrimaryButton = event.buttonState == MotionEvent.BUTTON_STYLUS_PRIMARY
  val isStylusSecondaryButton = event.buttonState == MotionEvent.BUTTON_STYLUS_SECONDARY
  return super.dispatchTouchEvent(event)
}