Sets whether or not this is a hoverable button.  When in a hoverable state, the icon will only
        be visible when the button is hovered on.

        :param      state | <bool>

def setHoverable(self, state):
        """
        Sets whether or not this is a hoverable button.  When in a hoverable state, the icon will only
        be visible when the button is hovered on.

        :param      state | <bool>
        """
        self._hoverable = state
        self._hoverIcon = self.icon()