dcampogiani

import android.graphics.Rect;
import android.support.v7.widget.RecyclerView;
import android.view.View;


public class SpacesItemDecoration extends RecyclerView.ItemDecoration {

    private final int leftSpace;
    private final int topSpace;
    private final int rightSpace;

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data class Data(val mail: String, val phone: String)

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val VALID_EMAIL_ADDRESS_REGEX = Pattern.compile("^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,6}$", Pattern.CASE_INSENSITIVE)!!
val VALID_PHONE_NUMBER_ADDRESS_REGEX = Pattern.compile("\\d{10}|(?:\\d{3}-){2}\\d{4}|\\(\\d{3}\\)\\d{3}-?\\d{4}", Pattern.CASE_INSENSITIVE)!!


fun validMail(input: String): Boolean {
    val matcher = VALID_EMAIL_ADDRESS_REGEX.matcher(input)
    return matcher.find()
}

fun validNumber(input: String): Boolean {

dcampogiani

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/primary_light"
    tools:context="com.danielecampogiani.androidfunctionalvalidation.MainActivity">

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fun String.optionMail(): Option<String> =
        when {
            validMail(this) -> this.some()
            else -> Option.None
        }

fun String.optionPhoneNumber(): Option<String> =
        when {
            validNumber(this) -> this.some()
            else -> Option.None

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class OptionViewModel : ViewModel() {

    private val mutableValidation: MutableLiveData<Option<Data>> = MutableLiveData()

    val validation: LiveData<Option<Data>>
        get() = mutableValidation


    fun validate(mail: String, phoneNumber: String) {
        val validationResult : Option<Data> = validateData(mail, phoneNumber)

dcampogiani

class OptionActivity : AppCompatActivity() {

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

        val viewModel = ViewModelProviders.of(this)[OptionViewModel::class.java]

        signup_button.setOnClickListener {
            viewModel.validate(email.text.toString(), number.text.toString())

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private fun handleNone() {
  val message = getString(R.string.option_wrong)
  showMessage(message)
}

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private fun handleSome(data: Data) {
  val message = "Mail: ${data.mail} Phone: ${data.phone}"
  showMessage(message)
}

dcampogiani

fun String.eitherMail(): Either<String, String> =
        when {
            validMail(this) -> this.right()
            else -> "Invalid email".left()
        }

fun String.eitherPhoneNumber(): Either<String, String> =
        when {
            validNumber(this) -> this.right()
            else -> "Invalid phone number".left()