samples/BindingDemo/app/src/main/res/layout/main_activity.xml

<!--
  Copyright (C) 2014 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.
  -->

<!--DISCLAIMER: This is a demo layout showing various calculations you can make in binding
expressions. It is usually a good practice to keep these expressions simple and use a ViewModel
if they are getting complex.-->
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:bind="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools">
    <data>
        <variable name="activity" type="com.android.example.bindingdemo.MainActivity"/>
        <!---->
        <import
            type="android.view.View"
            />
        <!---->
        <import type="com.android.example.bindingdemo.R.string" alias="Strings"/>
        <import type="com.android.example.bindingdemo.vo.User"/>
    </data>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        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"
        android:id="@+id/activityRoot"
        tools:activity=".MainActivity"
        android:clickable="true"
        android:onClick="@{activity.onUnselect}">
        <TextView
            android:id="@+id/title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@{@plurals/kittens(activity.tkAdapter.itemCount, activity.tkAdapter.itemCount)}">

        </TextView>

        <android.support.v7.widget.RecyclerView
            android:id="@+id/toolkittyList"
            android:layout_width="match_parent"
            android:layout_height="@dimen/list_height"
            bind:adapter="@{activity.tkAdapter}"
            ></android.support.v7.widget.RecyclerView>

        <View
            android:layout_width="match_parent"
            android:layout_height="10dp" />

        <android.support.v7.widget.CardView
            android:id="@+id/selected_card"
            bind:contentPadding="@{activity.selected == null ? 5 : activity.selected.name.length()}"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            bind:visibility="@{activity.selected == null ? View.INVISIBLE : View.VISIBLE}">

            <GridLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:columnCount="2"
                android:rowCount="4">

                <ImageView
                    android:id="@+id/selected_photo"
                    android:layout_width="@dimen/big_user_photo"
                    android:layout_height="@dimen/big_user_photo"
                    android:layout_column="0"
                    android:layout_row="0"
                    android:layout_rowSpan="2"
                    android:scaleType="fitCenter"
                    android:backgroundResource="@{activity.selected.photoResource}" />

                <EditText
                    android:id="@+id/selected_name"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_column="1"
                    android:layout_gravity="fill"
                    android:layout_row="0"
                    android:background="@android:color/holo_blue_dark"
                    android:gravity="center"
                    android:text="@{activity.selected.name}" />

                <EditText
                    android:id="@+id/selected_lastname"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_column="1"
                    android:layout_gravity="fill"
                    android:layout_row="1"
                    android:background="@android:color/holo_blue_bright"
                    android:gravity="center"
                    android:text="@{activity.selected.lastName}" />
                <Button
                    android:id="@+id/edit_button"
                    android:onClick="@{activity.onSave}"
                    android:text='@{"Save changes to " + activity.selected.name}'
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_column="1"
                    android:layout_gravity="right"
                    android:layout_row="2"/>

                <Button
                    android:id="@+id/delete_button"
                    android:onClick="@{activity.onDelete}"
                    android:text="@{activity.getString(activity.selected.group == User.KITTEN ? Strings.became_robot : Strings.became_kitten, activity.selected.name)}"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_column="1"
                    android:layout_gravity="right"
                    android:layout_row="3"/>

            </GridLayout>
        </android.support.v7.widget.CardView>
        <View
            android:layout_width="match_parent"
            android:layout_height="10dp" />
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text='@{activity.robotAdapter.itemCount + " Robots "}' />
        <android.support.v7.widget.RecyclerView
            android:id="@+id/robotList"
            android:layout_width="match_parent" bind:adapter="@{activity.robotAdapter}"  android:layout_height="@dimen/list_height"
            ></android.support.v7.widget.RecyclerView>
    </LinearLayout>
</layout>