schastev / cupCounter

Мобильное приложение на Android для подсчета кофейных напитков, необходимых для получения бесплатного кофе в кофейне.

TastyCount

Video Demo: https://youtu.be/ZTNs0kdhmqg

Description:

This Android app is a helper app for any shop that provides a free drink to the customer once the customer has purchased enough of those same drinks. The idea was inspired by a local coffee shop that used Google Sheets for this very purpose.

This app has:

1. Room database with the following structure:
   • customer ID
   • their first name
   • their phone number
   • the number of drinks they have purchased from the shop
   • date of registration
   • date of last update (called 'last visit' in the UI).
2. Main Screen where the user can search the database for customers by last digits of their phone number
3. New Customer screen where the user can add new customers. User's input is validated: only digits are allowed for the phone number field and only Russian OR English symbols can be saved in the name field
4. Customer Info screen which displays the information about the customer. It will show alerts when the customer is eligible for a freebie and if their database entry has not been updated in a certain number of days. The user can update the number drinks the customer purchased (both add and subtract though claiming), and edit customer's phone number
5. Settings screen where the user can customize eligibility criteria for the freebie, set the number of days for the alert to pop up. The user can also delete a customer from the database. This screen is meant to be used only by the shop manager and is therefore password-protected. The password can be changed on this same screen
6. Russian and English locales

Quality of life features

1. if a search query returns only one customer, their info page is opened automatically
2. Update and Revert Changes buttons on the Customer Info screen only show up if the user changed the number of drinks the customer purchased
3. the user can show or hide the dates of registration or last visit on the Customer Info screen
4. the user can decide if one drink should be automatically added to a customer upon registration

Project Structure

1. app/manifests contains general information about the app, description of its Activities ( screens)
2. app/java/com.tasty.count contains main classes used in this app:
   • /activity stores classes for the four main Activities of the app. Each of them contains methods responsible for the initialization of UI elements on screen, representation and handling of data
   • /customerlist stores helper files to display search results on the main screen in a specific format
   • /database stores all helper classes needed to work with the Room database:
     • AppDatabase is a class describing the database itself
     • Customer is a class describing a Customer
     • CustomerDAO is an interface that allows to make changes to the Customer counterparts in the database
     • DBClient is a client that allows the Activities to communicate with the database and provides a single copy of the database to all parts of the app
     • LocalDateTypeConverter is a simple converter for dates (from LocalDate to String and vise-versa)
   • /fragments stores helper fragments. They help organize the UI and simplify its editing
     • DialogFragment is responsible for the pop-up window when the user wants to edit customer's phone number
     • InfoDisplayFragment stores a template of a text field for the Customer info screen
     • PasswordPromptFragment is responsible for asking the user for the Admin password when entering Settings. It also checks it against the value stored in memory
     • SettingsFragment is responsible for handling and saving all of the app's preferences
     • SetPasswordFragment is responsible for changing Admin password. It asks for current password, and if it is correct, allows the user to input a new password. After validating it as it is typed and making sure it matches the input in the confirmation field, it allows the user to click "Save"
   • /toolbar contains a class that is responsible for drawing a toolbar with only required buttons. The idea is to let user go from any Activity to any other Activity in the app, but I don't want the user to see a link to the Settings screen when they are already there
   • CustomerGenerator is a class that populates the database with random customers with random dates of registration and last visit. Mainly there for testing purposes
   • Validator is a class responsible for validating user input
3. app/java/com.tasty.count (androidTest) contains a class with basic database tests
4. app/res contains .xml and other resources required for the app to work:
   • drawable, mipmap - icons for the UI and app itself
   • layout - descriptions of elements contained in each activity/fragment and their positions relative to each other and screen proportions
   • menu - variations of button combinations for the toolbar
   • values - colors and strings used throughout the app both in UI and code only. I tried to avoid passing strings directly to make my life easier in the future if I ever need to edit a parameter or a constant name
   • xml - contains a list of preferences on the Settings screen.

Design choices

1. InfoDisplayFragment had two default TextViews which I put into a fragment to save some time on formatting and styling. Afterwards I discovered Material TextInputLayout which basically takes care of all the formatting. So I could have gone back to a simpler structure and place four identical TextInputLayouts into an xml, but decided not to, because these fragments were a good exercise in displaying different pieces of information in different fragments instantiated from the same class.
2. Dates of last visit and registration were initially always visible, but after consulting a barista, it was decided that this information is not essential, so the switch to hide them was added to the settings screen. After thinking about it some more, I decided to make this setting accessible to the non-admin users as well, since the dates may be required sometimes.
3. Toggle for auto +1 for new customers was also initially on the Settings screen and available only to administrators. But after giving it some thought, I moved it to the New Customer screen: there may be situations where the user needs to use both states of the toggle in a short period and the admin may not be there to change it. The default value was set to Off: the user can add one drink really easily, but subtracting exactly one will require some effort and help from an administrator.