out.py

import os
from collections import OrderedDict
from IPython.display import display
import ipywidgets as widgets
from IPython.display import clear_output
import collections

class DictTable(collections.OrderedDict):
    def _repr_html_(self):
        html = ["<table width=100%>"]
        for key, value in self.items():
            html.append("<tr>")
            html.append("<td>{0}</td>".format(key))
            html.append("<td>{0}</td>".format(value))
            html.append("</tr>")
        html.append("</table>")
        return ''.join(html)

class general(object):
    def listloc(self):
        return DictTable([('WGS84-UTM19N', ['PERMANENT', 'UTM_user1', 'UTM_user2']), 
                          ('lonlat', ['PERMANENT', 'lonlat_user1', 'lonlat_user2']), 
                          ('nc_ll', ['PERMANENT'])
                         ])
    def environment_placeholder(self):
        return  DictTable([('DEBUG', '0'), 
                           ('GISBASE', '/usr/lib/grass72'), 
                           ('GISDBASE', '/home/epinux/work/data/grassdata'), 
                           ('GRASS_VERBOSE', '-1'), 
                           ('GUI', 'text'), 
                           ('LOCATION_NAME', 'WGS84-UTM19N'), 
                           ('MAPSET', 'PERMANENT')])
    def wizard2(self):
        self.out = widgets.Output()
        self.locations = self.listloc()
        self.location_options = sorted(list(self.locations.keys()))
        self.locationlist = widgets.Dropdown(
                options=list(self.locations.keys()),
                value=list(self.locations.keys())[-1],
                description='Location:',
            )

        self.maplist = widgets.Dropdown(
                options=self.locations[self.locationlist.value],
                value=list(self.locations[self.locationlist.value])[-1],
                description='Mapset:',
            )
        self.setgisdb = widgets.Button(
            description='Select',
            disabled=False,
            button_style='', # 'success', 'info', 'warning', 'danger' or ''
            tooltip='Set GRASS LOCATION & MAPSET',
            )    
        self.locationlist.observe(self.on_locations_change2, names='value')
        self.setgisdb.on_click(self.on_button_clicked2)
        display(widgets.HBox([self.locationlist, self.maplist]), widgets.VBox([self.setgisdb, self.out]))
    
    def on_locations_change2(self, locationame):
        self.maplist.options=self.locations[self.locationlist.value]
        with self.out:
            clear_output()
            display(self.listloc())

    def on_button_clicked2(self, b):
        with self.out:
            clear_output()
            display(self.environment_placeholder())