prebuilts/gradle/AutofillFramework/Application/src/main/res/layout/email_compose_activity.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
-->
<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:importantForAutofill="noExcludeDescendants"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin">

    <TextView
        android:id="@+id/email_compose_header"
        style="@style/TextAppearance.AppCompat.Large"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/spacing_normal"
        android:gravity="center"
        android:text="@string/navigation_button_email_compose_label"
        app:layout_constraintEnd_toStartOf="@+id/imageButton"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintHorizontal_chainStyle="spread"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <com.example.android.autofillframework.app.InfoButton
        android:id="@+id/imageButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/ic_info_black_24dp"
        app:dialogText="@string/email_compose_info"
        app:layout_constraintBottom_toBottomOf="@+id/email_compose_header"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/email_compose_header"
        app:layout_constraintTop_toTopOf="@+id/email_compose_header" />

    <TextView
        android:id="@+id/toLabel"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="@dimen/spacing_normal"
        android:layout_marginEnd="@dimen/spacing_normal"
        android:layout_marginStart="@dimen/spacing_normal"
        android:layout_marginTop="@dimen/spacing_normal"
        android:text="@string/to_label"
        app:layout_constraintBottom_toBottomOf="@+id/toText"
        app:layout_constraintEnd_toStartOf="@+id/toText"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/toText" />

    <EditText
        android:id="@+id/toText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="@dimen/spacing_normal"
        android:layout_marginTop="@dimen/spacing_normal"
        android:inputType="textEmailAddress"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="@+id/bodyText"
        app:layout_constraintTop_toBottomOf="@+id/email_compose_header" />

    <TextView
        android:id="@+id/bodyLabel"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="@dimen/spacing_normal"
        android:layout_marginStart="@dimen/spacing_normal"
        android:text="@string/body_label"
        app:layout_constraintBottom_toBottomOf="@+id/placeholder"
        app:layout_constraintEnd_toStartOf="@+id/bodyText"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/placeholder" />

    <EditText
        android:id="@+id/bodyText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="@dimen/spacing_normal"
        android:layout_marginStart="@dimen/spacing_normal"
        android:layout_marginTop="@dimen/spacing_normal"
        android:inputType="textMultiLine"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toEndOf="@+id/bodyLabel"
        app:layout_constraintTop_toBottomOf="@+id/toText" />

    <View
        android:id="@+id/placeholder"
        android:layout_width="match_parent"
        android:layout_height="36sp"
        android:layout_marginStart="8dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/bodyText" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/sendButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:backgroundTint="@android:color/holo_purple"
        android:src="@drawable/ic_send_white_24dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent" />

</android.support.constraint.ConstraintLayout>