Application to keep track of blood glucose values and calculate the average
- The user can input blood glucose values using a text field
- The values are only numeric and are validated with the device language format
- The blood glucose average is calculated and updated after each value is added
- The record values are persisted in a local database
- The record list displays a maximum of the last 100 records
- Each record displays its value, the date added, and the measure unit
- The supported measure units are mmol/L and mg/dL
- If the user changes the measure unit, all the values are changed instantly, including the displayed records and the one on the input text field
- The user can clear the list from the top menu by deleting all the stored values
- If there are no records, an empty state with a message is displayed
- If there are no records, the component to display the average is hidden
- If any error occurs, an error state with a message is displayed on the list
- A loading state is displayed while loading the values
- The conversion factor for blood glucose is 1 mmol/L = 18.0182 mg/dL
- The project is based on a layered architecture composed of a data, domain, and UI layer
- The information follows the unidirectional data flow pattern: data flows from layers data->domain->ui (dataSource->repositories->useCases->viewmodels->ui) and events go the other way ui->domain->data
- The data stream is implemented with flow
- The presentation layer is implemented using MVVM
- There are several use cases defined to handle data conversion that are generic enough to be reused in other future features of the application's viewmodels
- Dependency injection using Hilt
- Database uses Room
- All the UI was created in Compose
- There are data models defined for each layer used to communicate data with the layers below
- DataSource - Entities
- Repositories - Models
- ViewModels - UIState
- The data source component was implemented with Room and is used by default
- There is also an in-memory storage implementation but it is not currently used
- Records are always stored as mg/dL and converted upon display if required
- Dates are stored in UTC and converted to the local device time zone on load from the database
- There are two entities defined in the database - Record and Overview
- Record contains an individual blood glucose entry value and the date
- Overview holds the calculated values after a record is added. This avoids requesting all database values on each record addition to calculate the average
- Currently, there is only one Overview object in the database, but having the table ready will allow support for multiple users in the future
- Is stateless
- It abstracts communication with the data source
- Calculates the average
- Handles model conversion
- Is the state holder of uiState
- Handles subscription to repositories
- Handles user input and events
- Uses the domain layer to validate and convert data to be displayed on the UI depending on the filter selected and the device language
- Handles and displays errors
- The user can use the keyboard next button to add several values without hiding the keyboard
- Using the + button will always hide the keyboard
- The available languages are English and Spanish
- The record list can be paginated to display more than 100 records
- The maximum value supported for the average is the int capacity for the system. This can be increased using long if required
- Add features to remove a specific item
