Help regarding a "undefined" error

[Alejandro_Huber]

Hello all,

I am making an app which essentially allows you to store information on MIT app inventor components. I have it set up so that the data would store inside a list which would be associated with a tag/key in a dictionary. However, for some reason whenever I click the store button it gives me the "undefined" error and crashes my app.

Here is my code:

My UI:

Any thoughts?

[gordonlu310]

Can you explain what this is?

You cannot get a key from a string. Replace the 'error' string with create empty dictionary and test again.

This is all what I found.

[Alejandro_Huber]

It worked, thank you!