AlexMisiulia

    implementation 'com.android.support:recyclerview-v7:28.0.0'
    implementation 'com.android.support:design:28.0.0'

    def room_version = "1.1.1"

    implementation "android.arch.persistence.room:runtime:$room_version"
    annotationProcessor "android.arch.persistence.room:compiler:$room_version"

AlexMisiulia

@Target(AnnotationTarget.FUNCTION)
@kotlin.annotation.Retention(AnnotationRetention.RUNTIME)
@MapKey
annotation class ViewModelKey(val value: KClass<out ViewModel>)

@Module
abstract class ViewModelModule {
    @Binds
    @IntoMap
    @ViewModelKey(MainViewModel::class)

AlexMisiulia

class ViewModelFactory<T : ViewModel> @Inject constructor(private val viewModelProvider: Provider<T>) :
    ViewModelProvider.Factory {

    @Suppress("UNCHECKED_CAST")
    override fun <T : ViewModel> create(modelClass: Class<T>): T {
        return viewModelProvider.get() as T
    }
}

// usage in the client code 

AlexMisiulia

class MainActivity : AppCompatActivity() {

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

        val button: Button = findViewById(R.id.button)
        button.setOnClickListener {
            startActivity(Intent(this, DetailsActivity::class.java))
        }

AlexMisiulia

class MainActivity : AppCompatActivity() {

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

        phoneNumberEditText.addTextChangedListener(object : TextWatcher {
            override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
            }

AlexMisiulia

dependencies {
    implementation 'io.michaelrocks:libphonenumber-android:8.10.16'
}

AlexMisiulia

class MainActivity : AppCompatActivity() {
  private lateinit var phoneNumberUtil: PhoneNumberUtil

  override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      phoneNumberUtil = PhoneNumberUtil.createInstance(this)
  }
}

AlexMisiulia

private fun getCountryIsoCode(number: String): String? {
    val validatedNumber = if (number.startsWith("+")) number else "+$number"

    val phoneNumber = try {
        phoneNumberUtil.parse(validatedNumber, null)
    } catch (e: NumberParseException) {
        Log.e(TAG, "error during parsing a number")
        null
    }
    if(phoneNumber == null) return null

AlexMisiulia

override fun afterTextChanged(editable: Editable?) {
    val number = editable.toString()
    val countryIsoCode = getCountryIsoCode(number)
    countryTextView.text = countryIsoCode ?: "Can't detect a country"
}

AlexMisiulia

package com.sharyfire.countryphonedetector

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.text.Editable
import android.text.TextWatcher
import android.util.Log
import io.michaelrocks.libphonenumber.android.NumberParseException
import io.michaelrocks.libphonenumber.android.PhoneNumberUtil
import io.michaelrocks.libphonenumber.android.Phonenumber.PhoneNumber