Simple callback very slow when inside a tab

Dash Python
3

Thanks @chriddyp – this solution worked successfully for me, with the important addition of the suppression statement app.config['suppress_callback_exceptions'] = True
(see Chris’ response to this thread: dcc.Tabs: Filling tabs with dynamic content. How to organize the callbacks?)

Given this solution, I don’t see why anyone would want to use dcc.tabs Method #2 ( Content as Tab Children) – it basically makes it impossible to have any dynamic content in your tabbed app. That will be a dealbreaker for most of us, I think.

Anyway, here is my updated code, with Chris’ solution applied, in case others have the same problem.

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

app = dash.Dash()

app.config['suppress_callback_exceptions'] = True

app.layout = html.Div([
    dcc.Tabs(id="tabs", value='tab-1', children=[
        dcc.Tab(label='Tab one', value='tab-1'),
        dcc.Tab(label='Tab two', value='tab-2'),
    ]),
    html.Div(id='tabs-content')
])

@app.callback(Output('tabs-content', 'children'),
              [Input('tabs', 'value')])
def render_content(tab):
    if tab == 'tab-1':
        return html.Div([
            html.H3('Type any response in the box:'),
            dcc.Input(
                id='number-in',
                value=1,
                style={'fontSize':20}
            ),
            html.Button(
                id='submit-button',
                n_clicks=0,
                children='Submit',
                style={'fontSize':20}
            ),
            html.H4(id="response_div"),
            ],
            className='twelve columns')
    elif tab == 'tab-2':
        return html.Div([
            html.H3('Tab content 2')
        ])



# Call back number
@app.callback(
    Output('response_div', 'children'),
    [Input('submit-button', 'n_clicks')],
    [State('number-in', 'value')])
def output(n_clicks, number):
    return  'The response you have picked is: {}'.format(number),



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