Can anyone help me with an App I am trying to make for an engineering project?

[Tiffany Lopez]

Okay so i need help with making this app! what we want to do is make it use the bar code so that we can scan different products that is later placed in a list with the price that automatically adds the prices as you keep scanning. We also want it to be able to alert someone when they have reached a certain price like if x cost 5 and y cost 6 and you just wanted to spend 10 it alerts you that everything (x+y) equals more but for right now we just want the list and the adding of the prices.. We have it to where it will scan things and say what it is but then it just disappears when someone scans something else. 

The program we have so far is attached.
Please email me or reply back!!!!

[SteveJG]

1) It is easier on the forum to read (and you) if you use your PC to capture a screen image rather than providing a photo.  Win7 and above, learn to use the Sniping tool; Xp and above, do a Ctrl +PrntScrn and then open Paint and post the clipboard image to Paint.   In Mac...there is a similar tool.

2)" it will scan things and say what it is but then it just disappears when someone scans something else."   -- you have not saved anything...to a TinyDB for persistence   or to a List to save while the app is active but will lose the value when you exit the app.

3) You have a call TinyDB.GetValue  for a loaf of bread but nowhere is it saved. There is no call TinyDB.SaveFile   text    block in your code and there is no puzzle piece in the tag position of TinyDB.GetValue block.

4) You use two Notifiers (a better practice is to use one, they are re-usable) however then have to use different key works when calling the Notifier... Yes/No    ...   You would need to have a different response in the second Notifier ...perhaps Sure/Not OK   

Do you understand what you are coding:

Tutorials:

MIT tutorials     http://appinventor.mit.edu/explore/ai2/tutorials.html

AI2 free online eBook   http://appinventor.mit.edu/explore/ai2/tutorials.html   ... the links are at the bottom of the Web page.

Lists

Sajal    http://www.imagnity.com/tutorials/app-inventor/list-blocks-on-app-inventor/

TinyDB

ABG's example    https://docs.google.com/document/d/12t4HLNRepCnbmcfycdF8wSHWht_D1P8hKJpTknVDChY/edit   demonstrates filtering

Stephen's example    https://sites.google.com/site/stevozip/home/AI2/tinydb

Take a breath and realize, you code does exactly what you tell your app to do.   Fix the obvious problems with the code and return and ask a specific question.    you will get help.   It appears you are attempting to code the entire app at once.  Experienced developers might be able to do that.  What you need to do is code all the individual pieces separately perhaps; get each working as separate projects, then put the pieces together, once you know the pieces work.   It is much easier to debug that way.

Regards,

Steve