MVVM-implementation

A small Kotlin Android sample showing a phone-number / password login + register flow against a remote JSON API, organised as a thin AndroidViewModel + Repository split. The repository layer uses Volley for HTTP and the auth token is persisted in SharedPreferences. Branded "MVVM Login" (applicationId = com.shayan.mvvm_login).

Heads-up: the previous README claimed Room, LiveData, Hilt, Flow, Material Design, JUnit/Espresso tests, and an MIT license. Most of that is not in the code — see Honest limitations.

Status

• Working tree clean on master (last commit 46c442d, recent history is dominated by GitPulse marker commits).
• Remote: https://github.com/shayann07/MVVM-implementation.git.
• This README was rewritten from a code audit. The previous README's feature list did not match the actual code.

How it works

• view/MainActivitySplash — launcher activity. Inflates a Lottie animation_splash, waits ~5.65 s, then reads PrefsDatabase.user_token from SharedPreferences and routes to either MainActivityLogin (no token) or MainActivityHome (token present).

• view/MainActivityLogin — phone + password form. Calls AuthViewModel.loginUser(...). On success it writes the returned token to PrefsDatabase.user_token and starts MainActivityHome. Has a button that opens MainActivityRegister.

• view/MainActivityRegister — first/last name, phone, password, confirm-password. Builds a ModelUser and calls AuthViewModel.registerUser(...).

• view/MainActivityHome — a static iCloud-Reminders-style dashboard with cards (Today / Scheduled / All / Flagged / Completed) and two collapsible sections ("iCloud", "Outlook"). The toolbar overflow opens a PopupMenu whose only item ("Log Out") clears prefs and pops back to login.

• viewmodel/AuthViewModel — AndroidViewModel that holds a single AuthRepository and re-issues the same callback-based API inside viewModelScope.launch { … }. There is no LiveData, StateFlow, Flow, or Result wrapper; success/error callbacks are forwarded straight through.

• repository/AuthRepository — builds JSONObject request bodies and POSTs to:

  • https://cricdex.enfotrix.com/api/login
  • https://cricdex.enfotrix.com/api/register

  via Volley JsonObjectRequest, parsing success, message, and data.token from the JSON response. A new Volley.newRequestQueue(...) is allocated per call.

• model/ModelUser — data class with firstName, lastName, phone, password, cPass, token.

Tech stack

• Language / build: Kotlin, AGP via libs.versions.toml, JVM 11.
• App config: applicationId = com.shayan.mvvm_login, compileSdk = 35, minSdk = 24, targetSdk = 34, versionCode = 1, versionName = "1.0". viewBinding.enable = true.
• Dependencies: androidx.core.ktx, appcompat, material, volley, lottie, kotlinx-coroutines-android, androidx.activity, androidx.constraintlayout, androidx.lifecycle.viewmodel.ktx, androidx.fragment.ktx. JUnit + AndroidX-JUnit + Espresso for the default test scaffolds.
• Permissions: INTERNET only.

The repo does not use Hilt/Dagger, Room, Retrofit/OkHttp, Gson/Moshi, LiveData, Flow, Jetpack Compose, Navigation Component, DataStore, or WorkManager.

Project layout

MVVM-implementation/
├── app/
│   ├── build.gradle.kts                       # compileSdk 35, namespace com.shayan.mvvm_login
│   └── src/main/
│       ├── AndroidManifest.xml                # 4 activities, INTERNET only
│       ├── java/com/shayan/mvvm_login/
│       │   ├── model/ModelUser.kt
│       │   ├── repository/AuthRepository.kt   # Volley → cricdex.enfotrix.com
│       │   ├── viewmodel/AuthViewModel.kt     # AndroidViewModel
│       │   └── view/
│       │       ├── MainActivitySplash.kt      # 5.65 s token gate
│       │       ├── MainActivityLogin.kt
│       │       ├── MainActivityRegister.kt
│       │       └── MainActivityHome.kt        # PopupMenu logout
│       └── res/  layout/, drawable/, menu/, raw/animation_splash, values/
├── build.gradle.kts
└── gradle/libs.versions.toml

Setup / run

1. Clone, then provide a normal local.properties (gitignored).
2. Open in Android Studio and let Gradle sync.
3. ./gradlew :app:assembleDebug (or run from the IDE).

The login / register flow makes live calls to https://cricdex.enfotrix.com/api/{login,register} — without a valid account on that backend the flow cannot complete.

Honest limitations

• No Room, no LiveData, no Flow, no Hilt, no Retrofit. The previous README listed all of these. The actual stack is Volley + plain callbacks + SharedPreferences, with an AndroidViewModel that adds a coroutine wrapper around synchronous Volley dispatches.
• viewModelScope.launch is cosmetic. Volley already runs work off the main thread and delivers callbacks on it; the wrapping coroutine in AuthViewModel does no suspending work.
• Per-request Volley queue. AuthRepository calls Volley.newRequestQueue(context.applicationContext) on every login / register. Should be a single shared queue.
• Hardcoded API base URL. loginUrl / registerUrl are constants in AuthRepository. No BuildConfig field, no debug / release split, no flavour swap.
• Plaintext token storage. user_token is written to plain SharedPreferences. Use EncryptedSharedPreferences or DataStore + MasterKey for anything real.
• All four activities are android:exported="true". Only MainActivitySplash needs to be exported.
• Splash delay is ~5.65 s. Long for a launcher; consider androidx.core:core-splashscreen and a shorter timeout.
• MainActivityHome is a static mockup. No real reminder data — the cards and collapsible sections are pure UI.
• No LICENSE file at the repo root, despite the previous README claiming MIT.
• No tests beyond defaults. Only the generated ExampleUnitTest / ExampleInstrumentedTest are present.
• GitPulse marker comments. The previous README.md ended with <!-- commit N --> and <!-- gitpulse:contribution … --> lines from a contribution-marker tool; those are not present in this rewrite.