How to take the input of a dropdown and display its dependencies in another dropdown?

I want to make a dashboard where, say, in one dropdown I’ll have a list of countries,
and in the second dropdown I’ll have just cities of the country that I selected

**How can I do that ? **

You’ll want to use a callback that takes the value selected in the first dropdown as the Input, and Outputs options to the second. You can read about callbacks here: Part 3. Basic Callbacks | Dash for Python Documentation | Plotly

1 Like

thank youu so much , It works

But how I can selected by default all values of my countrie in the dropdown Multi ? do you have any idea ?

The selections in a dropdown are stored in its value property, so you can use your callback to update that at the same time as you update the options.