Dash callback as class method decorator

Dash Python
,
1

Dear developers,

I am recently into the Dash & Ploty community, and love the interactive app a lot! I am used to object-oriented programming and hope to take advantage of the class architecture to simplify the coding. I’ve read around and given a few attempts. Hope to share what I know and get advice if anyone happens to know how to do object-oriented programming for callbacks. Thanks in advance!

from dash import Dash, dcc, html, Input, Output

class App(Dash):

    def __init__(self, *arg, **kwarg):
        super().__init__(*arg, **kwarg)
        self.layout = html.Div([
            html.
            H6("Change the value in the text box to see callbacks in action!"),
            html.Div([
                "Input: ",
                dcc.Input(id='my-input', value='initial value', type='text')
            ]),
            html.Br(),
            html.Div(id='my-output'),
        ])

        self.callback(
            Output(component_id='my-output', component_property='children'),
            Input(component_id='my-input',
                  component_property='value'))(self.update_output_div)
     def update_output_div(self, input_value):
        return f'Output: {input_value}'


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

The above code works, but the callback must be called inside the init method away from the def update_output_div method. Can help one help to make something similar to the following work?

@Dash.callback(
        Output(component_id='my-output', component_property='children'),
        Input(component_id='my-input',
              component_property='value'))
def update_output_div(self, input_value):
    return f'Output: {input_value}'

self._callback_list and self.callback_map in def callback method stops me from achieving it. I am not sure how much work would be put into to get rid of the local copy and utilize the global GLOBAL_CALLBACK_LIST and GLOBAL_CALLBACK_MAP directly? Possible or not? Or other workarounds?

Sincerely,
Teng