code: def dataCollector( self ):
          
          func = None
          if ( self._dataCollectorRef ):
              func = self._dataCollectorRef()
          
          if ( not func ):
              self._dataCollectorRef = None
          
          return func
docs: Returns a method or function that will be used to collect mime data \
          for a list of tablewidgetitems.  If set, the method should accept a \
          single argument for a list of items and then return a QMimeData \
          instance.
          
          :usage      |from projexui.qt.QtCore import QMimeData, QWidget
                      |from projexui.widgets.xtablewidget import XTableWidget
                      |
                      |def collectData(table, items):
                      |   data = QMimeData()
                      |   data.setText(','.join(map(lambda x: x.text(0), items)))
                      |   return data
                      |
                      |class MyWidget(QWidget):
                      |   def __init__( self, parent ):
                      |       super(MyWidget, self).__init__(parent)
                      |       
                      |       self._table = XTableWidget(self)
                      |       self._table.setDataCollector(collectData)
                      
          
          :return     <function> || <method> || None