void CheckBeginDragItem(PointerEventData eventData)
{
if (!m_isDragingItem && m_curPreDragItem != null)
{
Vector2 checkAxis = horizontal ? Vector2.right : Vector2.up;
var delta = eventData.delta;
var angle = Mathf.Abs(Vector2.Angle(delta, checkAxis));
if (angle >= m_dragItemThreshold && angle <= 180 - m_dragItemThreshold)
{
m_isDragingItem = true;
ResetLastDragInfo();
m_curPreDragItem.CallOnBeginDrag(eventData);
}
}
}
