Reloads the contents for this box.

def reload(self):
        """
        Reloads the contents for this box.
        """
        enum = self._enum
        if not enum:
            return
        
        self.clear()
        
        if not self.isRequired():
            self.addItem('')
        
        if self.sortByKey():
            self.addItems(sorted(enum.keys()))
        else:
            items = enum.items()
            items.sort(key = lambda x: x[1])
            
            self.addItems(map(lambda x: x[0], items))