I am working on a Python Dash dashboard and have two dropdowns with the same options:

enter image description here

When I select an option in the first dropdown, how do I exclude the same option from the second dropdown? - So that I cannot choose the same material with both dropdowns.

Where and how would I do this in my code? I suppose it must be somewhere in my callbacks?

Any help is highly appreciated.

@app.callback(
    dash.dependencies.Output('dropdown3', 'options'),    
    [dash.dependencies.Input('dropdown2', 'value')])

def set_options1(first_dropdown):
    return [{'label': i, 'value': i} for i in all_options[first_dropdown]]

@app.callback(
    dash.dependencies.Output('dropdown3', 'value'),
    [dash.dependencies.Input('dropdown3', 'options')])

def set_1_value(available_options):
    return available_options[0]['value']

CodePudding user response：

You can certainly do this, and you're most of the way there. Use the value from the first dropdown to modify the options for the second one. Here's a way:

def set_options1(first_dropdown):
    return [
        {'label': i, 'value': i} 
        for i in all_options[first_dropdown] if i != first_dropdown
    ]