Dynamic Dropdown addition to dashboard

Dash Python
1

@chriddyp
I am a bit new to dash. Please help me out
I want to dynamically add a dropdown in my dashboard based on the requirements. For eg. if I choose just 3 columns from a dataframe for plotting, I can plot all of it without dropdown selections. However when there are more than 3 features, its not possible to represent all of it in a single plot, so I want to dynamically add dropdowns for all those extra columns(categorical). And based on the selection, it will show the plot.

Any help would be great.

2

Hi @nivek,
you should do the following:

  • Create a html.Div(children=[], id='div_for_dropdown') in your layout. This Div will be empty be default because the children property is an empty list.
  • Create a callback function that will populate your Div with a dropdown based on defined conditions.
@app.callback(
    Output('div_for_dropdown', 'children'),
    [Input(...),
     Input(...)])
def generate_dropdown(input_1, input_2):
    if condition_for_generating_dropdown:
        children = [
           dcc.Dropdown(...) 
        ]
    else:
        children = []
    return children

I hope this helps.