Calculate with app inventor

[newapp]

Hi,
I'm new to App Inventor and need some help...

This is a description what the app should do:
First the variables eb, gesammelt and m are initialized.
When button1 is clicked eb gains its value from the texbox1 and gesammelt and m gains its values from tinydb1.
Then, if eb is smaller as m, the new values for m and gesammelt are calculated.
The values of m and gesammelt are displayed in label3 and label4.
Then the values are stored in tinydb1.

I've got the following situation:
The values of m and gesammelt are not displayed in label3 and label4.
And I get an error message (see attached).
operation + can not accept "12.34"

Because it is my first app I would be very thankful for help.

Greetings,

newapp

[Taifun]

the value of the valueIfTagNotThere socket should be 0 in both cases
Taifun

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Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by Taifun.

[newapp]

hello Taifun!
Thanks a lot for your answer!
I changed both values but the error is still there...
What can I do?

[Taifun]

@newapp

And I get an error message (see attached).
operation + can not accept "12.34"

which means the issue occurs while you ae trying to use the add operation to add the 2 values gesammelt and eb
please provide the exact error message

use Do it to debug your blocks, see also tip 4 here App Inventor: How to Learn | Pura Vida Apps
see also Live Development, Testing, and Debugging Tools
Taifun

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Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by Taifun.

[newapp]

hello Taifun,
here is the error message:
thanks a lot for your help!

[uskiara]

Hello newapp,
I guess that what was saying Taifun is that you shall change the "type" of data in the valueIfTagNot There option: you shall use numerical type data (the blue block, instead of the purple ones). The error message you show still refers to string type. So please try to set a 0 value (zero) but change the type.
Hoping it can help.
Tschuess.

[ABG]

You also might have a non-number sneak in to your calculation through TextBox1.Text.

Instead of eating TextBox1.Text directly, filter it through this expression:

if is a number(TextBox1.Text
then TextBox1.Text
else 0

[Taifun]

learn to understand the error message

you also might want to clear TinyDB bfore continuing to test...

use Do it to debug your blocks, see also tip 4 here https://puravidaapps.com/learn.php
see also Live Development, Testing, and Debugging Tools
Taifun

[uskiara]

Dear all,
I come back to my previous post: if the variables contain string, the sum does not work and raises exactly the error message reported.
On the opposite, if the variables contain numbers, it works. And that's all.
Rgds.

[newapp]

Dear community members!
Thanks a lot for your very useful help!
With your help I was able to get the app running.
Thank you...
Greetings newapp

[uskiara]

Glad of that.
Cheers