Graph if empty dropdown

Dash Python
2

If you want to clear the graph, you can do:

@app.callback(...)
def update_graph(value):
    if value is None:
        return {'data': []}
    else:
        ...

If you don’t want your graph to update, see How to leave callback Output unchanged - #2 by nedned, e.g.

@app.callback(...)
def update_graph(value):
    if value is None:
        raise Exception()
    else:
        ...