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Delete/change a component's callback

Say I have a callback function that changes a Graph’s figure. Is it possible to decouple that callback from that Graph’s figure later, and even reassign another function as the callback to change Graph figure? Thanks.

Hi @mposcablo,

What kind of callback are you talking about? The on_change, on_selection, on_click, on_hover, and on_unhover callback registration functions all include an optional append argument. When append=False (the default) each time a callback function is registered it replaces all previously registered callbacks. If append=True then the new callback is added to the list of existing callbacks. And you can remove a callback by calling, for example, trace.on_selection(None).

Hope that helps!
-Jon

Hi @jmmease, can I do what you described in the Python Dash API? The ability to do what you just described is exactly what I need. However, looking at the dash.py source on Github, I don’t see a way to set an append parameter on callback().

Hi @mposcablo,

In Dash the callback definitions are defined in the application before the server starts and it’s not possible (at least not as far as I know) to modify them after the fact. If you want to talk about how to accomplish a particular workflow using Dash, I’d recommend describing a simple example of what you’re trying to do in a new forum post in the Dash category.

-Jon

Thanks @jmmease ! At least it’s clear to me now that this isn’t possible for now in Dash. I’ll describe what I ultimately want to do in a separate post when I get the chance.