Prevent Callbacks When Adding Elements To Dash Layout

Dash Python
1

Hi, first question on this forum.

So I’m making a Dash App which includes the functionality to press a button to add a particular element to the app layout (let’s call it the “button element”). The issue I’m having is that when I press that button, every callback attached to something in the button element is fired, both for the button element I just created and for every button element I had previously created. So if I have 3 callbacks to something in the button element, then the 5th time I press the button, the app is running 15 callbacks at once.

How can I prevent all these callbacks from firing every time I create a button element? I can provide more details if necessary.

(Edit: note that I’m using pattern-matching callbacks for this)

Thanks!

2

To disable triggering a callback when its outputs are first added to the page, pass prevent_initial_call=True when creating the callback, e.g.,

@app.callback([..outputs..],[..inputs..],[..states..],prevent_initial_call=True)
def some_callback(...):
    ....

This should work when using the pattern-matching syntax for outputs, inputs and/or states.

3

Thank you, this is exactly what I needed!