Mobile Code Challenge Android Solution

This is a solution to the mobile code challenge by a mobility company that operates in Berlin. It provides a mobile app that allows users to book pooled rides and track their progress.

Screenshot

Repository branches

• The solution was forked after 3-4 days of starting the challenge in a branch named: main in case it was needed by the examiners.

• Regarding extras and extras-2, the latter is the most recent. The biggest difference between those two is the layout changes and saving the map markers to be removed when the booking is closed.

• Regarding extras-after-deadline, I am experimenting for a bit.

About this project

The application is basically a simulation (visualization) on google map view for data sent from mobilityCompany's WebSocket.

mobilityCompany's team implemented the basic architecture for this code and based on this framework I implemented a solution that satisfies the requirements:

1. shows the user the live location of their assigned vehicle on a map
2. shows the ride's current status (waiting, in the vehicle, dropped off) in a UI component
3. shows the ride's pickup and drop-off addresses in a UI component

More details on the project

1. In the presentation layer, MVP model is used.
2. Dagger 2.0 is used for Dependency Injection through out the code.
3. The architecture model is very clean.
   1. Network is in a separate module and communicates with the Interactor. It also instantiates data classes like Event
   2. The Interactor communicated with presenters in each of the main and the two features
   3. Each one of the two features is in MVP model so the view and the model communicate through the presenters
   4. Each feature's mapper inherits data interface and overrides its mapDataModelToViewModel in different classes 4.OkHttp is used to handle communication with the WebSocket.
4. moshi is used to easily map the JSON objects with data.
5. RxKotlin and RxJava were used. Reactive programming is implemented for a more efficient use of resources setting the Event as the observables so that the observers (subscribers) only work when notified.

What did I implement?

1. Once the application opens it connects to the WebSocket and grabs the data which will:

   • Initialize the vehicle location.
   • Shows the pickup, drop-off, and intermediate stops markers.
   • Shows the status on the screen.
   • Shows the pickup and drop-off addresses on the screen.

2. With every "vehicleLocationUpdated" event: The vehicle marker will be animated

3. With every "intermediateStopLocationsChanged" event:

   • The stops markers will be drawn.
   • The screen shows the next stop address (assuming, the event will always be sent when a car reaches a stop)

4. With every "statusUpdated" and "bookingClosed" event: The status and the booking status will be updated on the screen. The program checks if status of booking is closed to clear all markers on screen.

Issues

1. When the internet connection is out for a bit while the application is running, it does not notify the user.
2. When the user zooms in with elevation, the vehicle marker rotation is not right.

Notes

1. There is no need for a release Google API key.
2. I thought about making the markers clickable to display addresses but I ended up not doing it as I thought it's redundant data that is not necessary since the next stop location is displayed on the screen.
3. I designed the drawables on illustrator for a vectorized code. However, I discovered that google map needs the markers to be an image/bitmap, so I had to convert the vector images .SVG to .PNG.

Assumptions

1. The webSocket will always send an event when the vehicle reaches an intermediate stop to update the "Heading to" text view.
2. Event.data from the webSocket may be null but Event.data[0].Address will never be null but could be empty.

What is missing?

1. Unit testing.
2. Handling webSocket's failure for a better UX.

How to use?

1. Import the project using Android studio.
2. Go to google_maps_api.xml
3. Google's API_key is set (open) to be used. However, if it was expired, kindly follow the instructions commented in the file to create a Google Maps API key and paste it in the aforementioned xml file.