Toggles whether or not the sub progress bar should be visible.
        
        :param      state | <bool>

def setShowSubProgress( self, state ):
        """
        Toggles whether or not the sub progress bar should be visible.
        
        :param      state | <bool>
        """
        ajax = self.currentMode() == XLoaderWidget.Mode.Spinner
        self._showSubProgress = state
        self._subProgressBar.setVisible(not ajax and state)