jupyter ipywidget file picker and browser / explorer

file_picker.py

import os
import ipywidgets as widgets


class FilePicker(object):
    """ipywidget for filepicking

    Display the widget in a notebook:

    >>> file_picker = FilePicker()
    >>> file_picker.widget

    Get the selected file path:

    >>> file_picker.file
    """

    def __init__(self, rows=20):

        self.__selected_dir = os.getcwd()

        self.__item_layout = widgets.Layout(width='auto')

        self.__nb_rows = rows

        self.__file_selector = widgets.Select(
            options=os.listdir(self.__selected_dir),
            rows=min(len(os.listdir(self.__selected_dir)), self.__nb_rows),
            layout=self.__item_layout
        )

        self.__open_button = widgets.Button(
            description='open',
            layout=widgets.Layout(flex='auto 1 auto', width='auto')
        )

        self.__parent_button = widgets.Button(
            icon='chevron-up',
            layout=widgets.Layout(flex='auto 1 auto', width='auto')
        )

        self.__file_selection = widgets.Text(
            value=os.path.join(
                self.__selected_dir, self.__file_selector.value),
            disabled=True,
            layout=widgets.Layout(flex='1 1 auto', width='auto')
        )

        def open_button_clicked(button):
            if os.path.isdir(self.__file_selection.value):
                self.__selected_dir = self.__file_selection.value
                self.__file_selector.options = os.listdir(self.__selected_dir)
                self.__file_selector.rows = min(
                    len(os.listdir(self.__selected_dir)), self.__nb_rows)

        def parent_button_clicked(button):
            self.__selected_dir, _ = os.path.split(self.__selected_dir)
            self.__file_selector.options = os.listdir(self.__selected_dir)
            self.__file_selector.rows = min(
                len(os.listdir(self.__selected_dir)), self.__nb_rows)
            self.__file_selection.value = os.path.join(
                self.__selected_dir, self.__file_selector.value
            )
            self.file = self.__file_selection.value

        def update_path(change):
            self.__file_selection.value = os.path.join(
                self.__selected_dir, self.__file_selector.value
            )
            self.file = self.__file_selection.value

        self.__parent_button.on_click(parent_button_clicked)
        self.__open_button.on_click(open_button_clicked)
        self.__file_selector.observe(update_path)

        self.widget = widgets.VBox([
            widgets.HBox([
                self.__parent_button, self.__file_selection, self.__open_button
            ]),
            self.__file_selector
        ])

        self.file = self.__file_selection.value