Write an Android Shop App

The requirement is to build an Android app that serves as catalog for a local shop. Users should be able to scan barcodes from a catalog, visualise the description of the item and add it to their basket specifying quantity. Then when’t they’re done, proceed to submit the order via email to a local email to be specified, using only the phone number and name. The app is made of 3 screens. Welcome screen The user opens the app, then he visualises the welcome screen. There is a button there to proceed to the next step. At this point, the basket will be empty. List screen The list screen is where the user will be able to add items to the list and see what’s in it’s list. It’s a standard scrollable list. It’s a simple list, stored in memory in the device (it could be done in XML or json, not needed to use SQLite). If the user selects one of the items of the list, a dialog will be presented with the description of the item and it will be able to modify the quantity or cancel the change. The screen has three buttons at the top. On the left there is the back button, where the user will go back to the welcome screen. If the user press this button, an alert should be presented asking if he is sure to go back. If the user continues, the list is deleted. If the user cancels, stays in the list screen. On the right there are two buttons. One button will open a camera interface, which will scan the barcodes (EAN-13 barcodes) The second button will present the checkout screen. This button will be only available when the user already has one product on the list. Camera scanner screen This screen is just the camera interface, which will try to detect a barcode. If a barcode is detected, then it will go back and present a dialog where the user will be able to see details about the product and select the quantity. It will have also two buttons, one to cancel and one to add the product to the basket. Please follow the designs