example_utils.py 文件源码

def on_value_change(self, change, url):
        next_url = change['new']
        if next_url is None: # 'Select...' chosen
            return
        if next_url.endswith('.grb'): # File reached
            return self.select_url(next_url)
        [w.close() for w in self.elts]
        links = self.get_links(next_url,
                               href_filter=(self.dir_and_not_data
                                            if next_url == self.base_url
                                            else self.dir_or_grib))
        if not links:
            return
        next_dd = widgets.Select(
            options=links,
            description='', #urlparse(url).path,
        )
        next_dd.observe(partial(self.on_value_change, url=next_url), names='value')
        lbl = widgets.Label(urlparse(next_url).path, layout=self.label_layout)
        hbox = widgets.HBox([lbl, next_dd])
        self.elts = [hbox, lbl, next_dd]
        display(hbox)