user login using viewmodel and retrofit

Question

im trying to do login using retrofit and viewmodel

i have done successfully login with only retrofit...referred this tutorial--> https://www.youtube.com/watch?v=j0

Answer 1

class LoginActivity : BaseClassActivity() {
    private val viewModel by viewModels()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.login_activity)

        val button = findViewById(R.id.plusbutton)
        val forgotpassword = findViewById(R.id.forgotpassword)

        button.setOnClickListener {
            val i = Intent(applicationContext, RegisterActivity::class.java)
            startActivity(i)
        }

        forgotpassword.setOnClickListener {
            val i = Intent(applicationContext, ForgotPassword::class.java)
            startActivity(i)
        }

        loginuser.onTextChanged {
            viewModel.user.value = it.toString()
        }

        loginpassword.onTextChanged {
            viewModel.password.value = it.toString()
        }

        loginbtn.setOnClickListener {
            viewModel.login()
        }

        viewModel.loginResult.observe(this) { result ->
            when (result) {
                UserMissing -> {
                    Toast.makeText(
                        applicationContext, "Data is missing", Toast.LENGTH_LONG
                    ).show()
                    loginuser.error = "Email required"
                    loginuser.requestFocus()
                }
                PasswordMissing -> {
                    loginpassword.error = "Password required"
                    loginpassword.requestFocus()
                }
                NetworkFailure -> {
                }
                NetworkError -> {
                    showToast(applicationContext, result.userMessage)
                }
                Success -> {
                    val intent = Intent(applicationContext, HomeActivity::class.java)
                    intent.flags =
                        Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
                    showToast(applicationContext, res.body()?.message)
                    Log.d("kjsfgxhufb", response.body()?.status.toString())
                    startActivity(intent)
                    finish()
                }
            }.safe()
        }
    }
}

class LoginViewModel(private val savedStateHandle: SavedStateHandle) : ViewModel() {
    sealed class LoginResult {
        object UserMissing : LoginResult(),

        object PasswordMissing : LoginResult(),

        class NetworkError(val userMessage: String) : LoginResult(),

        object NetworkFailure : LoginResult(),

        object Success : LoginResult()
    }

    val user: MutableLiveData = savedStateHandle.getLiveData("user", "")
    val password: MutableLiveData = savedStateHandle.getLiveData("password", "")

    private val loginResultEmitter = EventEmitter()
    val loginResult: EventSource = loginResultEmitter

    fun login() {
        val email = user.value!!.toString().trim()
        val password = password.value!!.toString().trim()

        if (email.isEmpty()) {
            loginResultEmitter.emit(LoginResult.UserMissing)
            return
        }


        if (password.isEmpty()) {
            loginResultEmitter.emit(LoginResult.PasswordMissing)
            return
        }

        RetrofitClient.instance.userLogin(email, password)
            .enqueue(object : Callback {
                override fun onFailure(call: Call, t: Throwable) {
                    Log.d("res", "" + t)
                    loginResultEmitter.emit(LoginResult.NetworkFailure)
                }

                override fun onResponse(
                    call: Call,
                    response: Response
                ) {
                    var res = response

                    Log.d("response check ", "" + response.body()?.status.toString())
                    if (res.body()?.status == 200) {
                        SharedPrefManager.getInstance(applicationContext).saveUser(response.body()?.data!!)
                        loginResultEmitter.emit(LoginResult.Success)
                    } else {
                        try {
                            val jObjError =
                                JSONObject(response.errorBody()!!.string())
                            loginResultEmitter.emit(LoginResult.NetworkError(jObjError.getString("user_msg")))
                        } catch (e: Exception) {
                            // showToast(applicationContext,e.message) // TODO
                            Log.e("errorrr", e.message)
                        }
                    }
                }
            })
    }
}

Using

allprojects {
    repositories {
        // ...
        maven { url "https://jitpack.io" }
    }
    // ...
}

implementation 'com.github.Zhuinden:live-event:1.1.0'

EDIT: some missing blocks to actually make this compile:

fun  T.safe(): T = this // helper method

These dependencies in Gradle

implementation "androidx.core:core-ktx:1.3.2"
implementation "androidx.activity:activity-ktx:1.1.0"
implementation "androidx.fragment:fragment-ktx:1.2.5"
implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:2.2.0"

Also add

android {
  compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_8
    targetCompatibility JavaVersion.VERSION_1_8
  }

  kotlinOptions {
    jvmTarget = "1.8"
  }
}

To access applicationContext in ViewModel, you'll need to use AndroidViewModel instead of ViewModel

class LoginViewModel(
    private val application: Application,
    private val savedStateHandle: SavedStateHandle
): AndroidViewModel(application) {
    private val applicationContext = application

And that should fix it

EDIT: apparently the "onTextChanged" is doAfterTextChanged in ktx, what I use is this:

inline fun EditText.onTextChanged(crossinline textChangeListener: (String) -> Unit) {
    addTextChangedListener(object : TextWatcher {
        override fun afterTextChanged(editable: Editable) {
            textChangeListener(editable.toString())
        }

        override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
        }

        override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
        }
    })
}