类型 PointerEvent

type PointerEvent struct {
	Kind      PointerEventKind
	Button    PointerButton
	Modifiers Modifiers
	X         float32
	Y         float32
	// ScreenX and ScreenY are the same point in screen coordinates: logical
	// pixels from the top-left corner of the primary display, y down, the
	// coordinates app.Window.Frame is in. A press that is held keeps reporting
	// them when the pointer leaves the window, which is how a drag finds the
	// window it ends over. Exit events carry none.
	ScreenX, ScreenY float32
	Viewport         Size
	Target           ID
	Captured         bool
	ClickCount       int
}