Checklist callback adds new values to old values

Dash Python
1

I’m currently using a checklist that updates with the columns of a table whenever a new table is created.

convert = lambda text: int(text) if text.isdigit() else text 
alphanum_key = lambda key: [ convert(c) for c in re.split('([0-9]+)', key) ]
sortlist = sorted(selected, key = alphanum_key)
inters_df = {k: inters_df[k] for k in sortlist}

This code simply just takes the columns of the table and sorts them into alphabetical order. The column names of the sorted dataframe (sortlist) is then returned to the options parameter of the checklist component. So on the initial creation of a table, the value parameter could look like this:

['A1', 'A2', 'A4']

However, a callback was implemented to recreate the table in the exact same format with any new datasets that the user uploads. So the column names would probably change. I set the checklist options through the exact same process as above, but when the user selects from this new checklist, it would add the selected options on top of the ones selected before the new table was created.

['A1', 'A2', 'A4', 'B1', 'B2']

Which is weird because the checklist itself has been updated with the correct options, without the options of the previous table. The above was printed when using a print statement directly on the State of the value parameter of the checklist.

Anyone know what could be causing this?

Thank you!

1 Like
2

Hello @hypervalent,

It’s hard to say without seeing your actual callback and inputs/outputs.

It sounds like you are just building it somehow.

3

Never mind! I guess for some reason, the data passed to the value parameter (not the options for some reason) persists in subsequent callbacks.
I just put an extra output in the table generation callback to clear that value parameter before running the callback on it.
Thank you!

1 Like