Android in Action: Implement MVP(Model - View - Presenter) Architecture for Android Application. Past 1: Analysis the requirement

Overview

Let's discuss the way implementation Android MVP Architecture in practical case.

1. Part1: Overview MVP Architecture and Login function's requirement
2. Part 2: Implement source code by Kotlin in Android Application

We'll design MVP Architecture like as below

1. View layer:
   • UI :display data -> configure activity/fragment layout, binding data, binding action -> with context of application
   • The adapter: transformation data if necessary (usually using with recycle view,...)
2. Model layer:
   • network and DAO: handle the way how to get/load data (from cache, from REST API,...)
   • entity: just informations which functions need. (It can be store in Room database,...)
3. Presenter layer:
   • presenter: extend ViewModel()/AndroidViewModel()
     • kepp data variable of layout for binding data
     • has state -> decides the View's behavior (implement by LiveData)
     • keep entity references to hold data for View
     • keep DAO/network references to get/load data
     • optional: keep/refer other business/validate references for owner business
   • other business, validate,...

Requirement:

User want to build a function called Login. It has:

• GUI: display data and keep interacting with user.
• data: store user's data to use for login business.
• login manual: main business.
• single sign on: auto login when user has author before.
• validate: validate data.
• show message: info and error messages.

Let's analysis user's business

we have a Login function specs as below:

1. Display screen
2. sso (auto login) by cache
   • sso -> false: user must to login manually
   • sso -> true: auto redirect to home screen
3. Login manual
   • handle user's input: both (username, passwork)are fill -> enable login button, else disable
   • validate: (disable login button when user's input invalid else enable.)
     • username is not empty
     • username's length is between 6-8 characters
     • password is not empty
     • password's length is between 6-10 characters
     • both username and password can not contains space character
   • login action
     • call RESTfull API to execute login with params: username, password by JSON format
     • Success:
       • Update cache login state for login next time
       • Redirect home screen
     • False: show error from server