def METHOD_NAME(self):
    """Handles when the current index of the combobox changes."""
    idx = self.currentIndex()
    if idx == SELECT_OTHER:
        external_path = self.select_directory()
        if len(external_path) > 0:
            self.add_external_path(external_path)
            self.setCurrentIndex(self.count() - 1)
        else:
            self.setCurrentIndex(CWD)
    elif idx == CLEAR_LIST:
        reply = QMessageBox.question(
                self, _("Clear other directories"),
                _("Do you want to clear the list of other directories?"),
                QMessageBox.Yes | QMessageBox.No)
        if reply == QMessageBox.Yes:
            self.clear_external_paths()
        self.setCurrentIndex(CWD)
    elif idx >= EXTERNAL_PATHS:
        self.external_path = str(self.itemText(idx))