Help with bar code !!!!!

[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!!!!