Returns the uifile for this scaffold.
        
        :return     <str>

def uifile(self):
        """
        Returns the uifile for this scaffold.
        
        :return     <str>
        """
        output = ''

        # build from a zip file
        if zipfile.is_zipfile(self.source()):
            zfile = zipfile.ZipFile(self.source(), 'r')
            if 'properties.ui' in zfile.namelist():
                tempdir = tempfile.gettempdir()
                output = os.path.join(tempdir,
                                      '{0}_properties.ui'.format(self.name()))

                f = open(output, 'w')
                f.write(zfile.read('properties.ui'))
                f.close()
            zfile.close()

        else:
            uifile = os.path.join(os.path.dirname(self.source()),
                                  'properties.ui')
            if os.path.exists(uifile):
                output = uifile

        return output