datepicker doesn't open if date values are None

[chriddyp]

Originally reported in https://community.plot.ly/t/datepickerrange-clearable-in-tabs-not-working-as-expected/6850/4

import dash
from dash.dependencies import Input, Output
import dash_core_components as dcc
import dash_html_components as html
from datetime import datetime as dtime

app = dash.Dash()


app.config['suppress_callback_exceptions'] = True
app.layout = html.Div([
    dcc.DatePickerRange(
        id='Dr1',
        clearable=True,
        reopen_calendar_on_clear=True,
        start_date_placeholder_text='Select a date',
        end_date=dtime.today().strftime("%Y-%m-%d")
    ),
    html.Div(id='output')
])


@app.callback(
    Output('output', 'children'),
    [Input('Dr1', 'start_date'),
     Input('Dr1', 'end_date')])
def dates_selected(start_date, end_date):
    value = "From- %s  To-   %s" % (start_date, end_date)
    return value


if __name__ == '__main__':
    app.run_server(debug=True)

Quite a few error messages in the console

[xblad]

@chriddyp
Hi Chris, I think the issue above is related to the fact, that DatePickerRange's attribute initial_visible_month isn't defined. Maybe the default value could be set (e.g. datetime.today()) and it would solve the issue (AirBnB's date-picker shows current month by default as well).

[90debasish]

Hi Chris,

in the above example what i am facing issue is :

1. In the beginning when the date picker starts it prints as None- This is completley ok
2. However when you select some date and then let say clear those dates then it still shows the previous value but it should show as None since the dates are clear.

The problem with the initial approach is:

1. Let say we selected some date from and end; we get the data from those period- This is completley ok
2. However let say if we want only data which is less than the end period after previous selection.-------> here we are not able to do so since we still have from value which still has the previous value even if we clear it in the date picker

[byronz]

issue has been fixed in

dash                 1.0.2
dash-core-components 1.0.0
dash-html-components 1.0.0
dash-renderer        1.0.0
dash-table           4.0.2