fragment_login.xml

<?xml version="1.0" encoding="utf-8"?>
<layout 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">

    <!--suppress AndroidUnknownAttribute -->
    <data class="LoginFragmentBinding">
        <variable
            name="viewModel"
            type="com.melnykov.mvvmtesting.ui.login.LoginViewModel" />
    </data>

    <android.support.constraint.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context="com.melnykov.mvvmtesting.ui.login.LoginFragment">

        <EditText
            android:id="@+id/edit_text_email"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:hint="Email"
            android:inputType="textEmailAddress"
            android:text="@={viewModel.emailField}"
            app:addTextChangedListener="@{viewModel.emailTextChangedListener}"
            app:layout_constraintBottom_toTopOf="@+id/edit_text_password"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintVertical_chainStyle="packed" />

        <EditText
            android:id="@+id/edit_text_password"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:hint="Password"
            android:inputType="textPassword"
            android:text="@={viewModel.passwordField}"
            app:addTextChangedListener="@{viewModel.passwordTextChangedListener}"
            app:layout_constraintBottom_toTopOf="@+id/button_sign_in"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/edit_text_email" />

        <Button
            android:id="@+id/button_sign_in"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:enabled="@{viewModel.isLogInButtonEnabled}"
            android:onClick="@{() -> viewModel.onSignInButtonClicked()}"
            android:text="Sign in"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/edit_text_password" />

        <TextView
            android:id="@+id/label_forgot_password"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:onClick="@{() -> viewModel.onForgotPasswordLabelClicked()}"
            android:text="Forgot password?"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/button_sign_in" />

        <FrameLayout
            android:id="@+id/progress_overlay"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:background="#CCFFFFFF"
            android:clickable="true"
            android:elevation="16dp"
            android:focusable="true"
            android:visibility="@{viewModel.isProgressBarVisible()}"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            tools:ignore="UnusedAttribute">

            <ProgressBar
                android:layout_width="96dp"
                android:layout_height="96dp"
                android:layout_gravity="center" />

        </FrameLayout>

    </android.support.constraint.ConstraintLayout>

</layout>