Android rider application

Components

Service Diagram

1. RideStatusService

Foreground service which listens to ride status changes. Application will keep RideStatusService alive (using startForeground and STICKY mode) during the ride. When there is no active ride service is shut down.

2. StateManager

Keeps track of current ride and unrated ride (if any). Exposes reactive API for publish-subscribe pattern. Model in MVVM. StateManager is bound to Android Application's lifecycle.

3. DataManager

Stores session data and encapsulates networking. Exposes reactive API for publish-subscribe pattern. Model in MVVM. DataManager is bound to Android Application's lifecycle.

4. Representation

UI-related part uses MVVM pattern with data binding. Views and ViewModels both bound to Android Activity/Fragment lifecycle. Views are recreated on configuration changes, ViewModels - mostly not. Approach is similar to Android Architecture Components

5. Managers

There is a bunch of specialized managers which names are mostly self-explaining:

• ConfigurationManager updates configuration based on location
• LocationManager provides location updates
• PrefManager persists user data
• AppNotificationManager manages device notifications and in-app messages
• ConnectionStateManager listens to network and server reachability

Android driver application

Components

Service Diagram

1. EngineService

Entry point which starts main application's components. When driver is online or in ride, application will keep EngineService alive (using startForeground and STICKY mode). When driver is offline, service will run no longer than any visible activity.

2. StateManager

Application uses state machine to manage driver states.

StateManager's responsibilities are:

• switching states
• synchronizing with server state
• utilizing server events

StateManager lifecycle is bound to EngineService

3. EngineState

Driver state representation eg. OnlineState, PendingAcceptState, AcceptedState etc. Each state is responsible for actions specific to this state:

• using local and third-party services (location, tracking, direction)
• invoking server API requests (go online, accept ride, etc)
• caching data during network failures

EngineState can be treated as data model.

4. UIStrategy

Each state has corresponding UI strategy, which reflects data changes on screen. UIStrategy is bound to Android lifecycle and is only active during onStart/onStop.

5. Managers

There is a bunch of specialized managers which names are mostly self-explaining:

• LongPollingManager listens to LP events
• PendingEventsManager works with cached data which must be sent when connection restored
• ConfigurationManager updates configuration based on location
• DriverLocationManager sends location updates based on current state and configuration settings
• RideRequestManager provides data about request types which driver is eligible to work with
• AirportQueueManager keeps track of driver's position in airport queue
• PrefManager persists user data
• AppNotificationManager manages device notifications and in-app messages
• ConnectionStateManager listens to network and server reachability
• DataManager stores session data and encapsulates networking

License

Distributed under the MIT license. See LICENSE for more information.