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Multiple callbacks to same output [Again]- this time with a datatable

Dash
#1

Hi, I know that I can’t have multiple callbacks to the same output, but I’m confused about what to do in the meantime.

I have a datatable and want ability for users to either click on AddRow to append a row and then be able to type numbers in directly, or click on Upload to get a CSV and populate all in one go. I can do either one of these with a callback, but…

… what would be recomendations or hints to optimal solution?

#2

You group all operations related to an output into one callback. In some cases this can make the code less readable, so I have written a small utility class DashCallbackBlueprint that takes care of it. Here is an example,

import dash
import dash_html_components as html
from dash.dependencies import Output, Input
from dash_extensions.callback import DashCallbackBlueprint

    
app = dash.Dash()
app.layout = html.Div([html.Button("Button 1", id="btn1"), html.Button("Button 2", id="btn2"), html.Div(id="div")])
dcb = DashCallbackBlueprint() 


@dcb.callback(Output("div", "children"), [Input("btn1", "n_clicks")])
def click_btn1(n_clicks):
    return "You clicked btn1"


@dcb.callback(Output("div", "children"), [Input("btn2", "n_clicks")]) 
def click_btn2(n_clicks):
    return "You clicked btn2"


dcb.register(app)  

if __name__ == '__main__':
    app.run_server()
#3

Thanks, merging the callbacks did indeed solve the problem.