public function __construct($dropParams)
{
$this->_dragElementId = $dropParams->DragElementID;
$this->_screenX = $dropParams->ScreenX;
$this->_screenY = $dropParams->ScreenY;
$this->_offsetX = isset($dropParams->OffsetX) ? $dropParams->OffsetX : false;
$this->_offsetY = isset($dropParams->OffsetY) ? $dropParams->OffsetY : false;
$this->_clientX = $dropParams->ClientX;
$this->_clientY = $dropParams->ClientY;
$this->_shiftKey = TPropertyValue::ensureBoolean($dropParams->ShiftKey);
$this->_ctrlKey = TPropertyValue::ensureBoolean($dropParams->CtrlKey);
$this->_altKey = TPropertyValue::ensureBoolean($dropParams->AltKey);
}