Clears out all the items from this tab bar.

def clear(self):
        """
        Clears out all the items from this tab bar.
        """
        self.blockSignals(True)
        items = list(self.items())
        for item in items:
            item.close()
        self.blockSignals(False)

        self._currentIndex = -1
        self.currentIndexChanged.emit(self._currentIndex)