Goal

Create a master-detail application that contains at least one dependency. This application should display a list of items obtained from an iTunes Search API and show a detailed view for each item.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

Cocoapods

Before you could build and run the project you need to install the cocoapod dependencies. Assuming you aleady have installed cocoapods. Open a terminal at the root of the project and execute the command.

$ pod install

After everything is installed locate the generated workspace file and open the project using that to include the pod project.

Features

• Search and show list of movies from iTunes
• View movie details
• Light/Dark mode
• Last Screen is saved (Data Persistence)

UI/UX Design

Movies Prototype

Colors

Light Theme

• Background Color - #F9F9F9
• Card Background Color - #FFFFFF
• Text Color - #000000

Dark Theme

• Background Color - #050505
• Card Background Color - #191717
• Text Color - #FFFFFF

Typography

Font

• Proxima Nova (Regular, Bold)

Architectural pattern

I decided to use the most famous design pattern in iOS Development, MVVM or Model, View, ViewModel. With the combination of Combine Framework for handling asynchronous task.

MVVM is a design pattern that seperate the objects into three categories:

• Model - Plain structure of data that usually receives from the api or local database.
• View - Displays the current UI of the screen. Receives updates from the ViewModel.
• ViewModel - The middleman between the model and view. Contains the business logic of the feature/screen.

Pros and Cons of Using MVVM

Pros

• Separates the business logic to view. This means it is easier to conduct a unit test.
• Objects are bind to the view so any changes from api/local database will automatically updates the view.
• Good for small projects.

Cons

• Not preferrable for big projects but still usable.
• Need time to learn because of reactive programming.

Source

All views are created using storyboard.

MovieListViewController

The MovieListViewController conforms to the View protocol. The MovieListViewController depends on the ViewModel designed to manage user input and the display data. Whenever the api/local database did some changes the ViewModel updates the MovieListViewController with ScreenState.

enum ScreenState: Equatable {
    case loading(Bool)
    case displayList([MainMovies])
    case error(String)
}

MovieListViewModel

This is the ViewModel that is injected to MovieListViewController and defines what the screen is to show and how it behaves. MovieListViewModel conforms to ViewModel protocol.

protocol ViewModel {
    
    //  Setting up the view state. Check persist data
    func setupPersistedData()
    
    //  Handles the search operation
    func search(query: String)
    
    //  Handles changing the app state and save it to UserDefaults
    //  When state is details, movieId should be saved
    func change(state: AppState, movieId: Int?)
}

APIClient

This is the class that handles the api request operation and it used by MovieListViewModel. Combine framework is implemented here to handle and set the api request to run in background thread. The APIClient conforms to Client protocol.

protocol Client {
    
    //  A request to search for a movie in iTunes
    func requestSearchMovies(query: String,
                             country: Country) -> AnyPublisher<[MovieList.Result], AFError>
    
}

DatabaseManager

This is the class that handles the local database operation and it used by MovieListViewModel. Combine framework is also implemented here. The function return the data via publisher. The DatabaseManager conforms to Database.

protocol Database {
    
    //  A request to save all movie in database
    func saveAllMovies(list: [MainMovies])
    
    //  A request to get all movies from the database
    func getAllMovies() -> AnyPublisher<[Movie], Error>
    
    //  A request to delete all items in the database
    func deleteAllMovies()
    
}

Persistence

Persistence takes place by saving the app current screen before it closes then restore the last screen when the app restart.

Core Data is used to save the data that received from the api. The DatabaseManager handles the interaction with the Core Data and operates the get, save, delete method. Whenever the app received a data from api via search, Delete the old data that has been saved last time then save a new set of list. Below are the attributes that is being saved in the database.

Attribute Name	Type
trackPrice	Double
previewUrl	String
name	String
longDescription	String
imageUrl	String
id	Integer 32
genre	String
currency	String

Specifications

• Handles iOS 13 and up
• Combine Framework for handling asynchronous task
• Swift 5
• Core Data

Dependencies

• Alamofire - HTTP networking library
• Kingfisher - Downloading and caching images from the web

Tools

• Adobe XD
• Xcode
• Cocoapods

Author

Adrian Jun Seraspi - LinkedIn, Google Playstore