classpath 'com.android.tools.build:gradle:1.2.3'
classpath 'com.android.databinding:dataBinder:1.0-rc0'

apply plugin: 'com.android.databinding'

<layout xmlns:android="http://schemas.android.com/apk/res/android">
  <data>
  </data>
  <!--原先的根节点（Root Element）-->
  <LinearLayout>
  ....
  </LinearLayout>
</layout>

public class User {
  private final String firstName;
  private final String lastName;
  private String displayName;
  private int age;

  public User(String firstName, String lastName) {
    this.firstName = firstName;
    this.lastName = lastName;
  }

  public User(String firstName, String lastName, int age) {
    this(firstName, lastName);
    this.age = age;
  }

  public int getAge() {
    return age;
  }

  public String getFirstName() {
    return firstName;
  }

  public String getLastName() {
    return lastName;
  }

  public String getDisplayName() {
    return firstName + " " + lastName;
  }

  public boolean isAdult() {
    return age >= 18;
  }
}

<data>
  <variable name="user" type="com.liangfeizc.databindingsamples.basic.User" />
</data>

<data>
  <import type="com.liangfeizc.databindingsamples.basic.User" />
  <variable name="user" type="User" />
</data>

<variable name="firstName" type="String" />

@Override
protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  ActivityBasicBinding binding = DataBindingUtil.setContentView(
      this, R.layout.activity_basic);
  User user = new User("fei", "Liang");
  binding.setUser(user);
}

<data>
  <variable name="firstName" type="String" />
  <variable name="firstName" type=""
</data>

setFirstName(String firstName);
setLastName(String lastName);

<TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@{user.lastName}" />

public class MyStringUtils {
  public static String capitalize(final String word) {
    if (word.length() > 1) {
      return String.valueOf(word.charAt(0)).toUpperCase() + word.substring(1);
    }
    return word;
  }
}

<import type="com.liangfeizc.databindingsamples.utils.MyStringUtils" />

<TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@{StringUtils.capitalize(user.firstName)}" />

<import type="com.example.home.data.User" />
<import type="com.examle.detail.data.User" />
<variable name="user" type="User" />

<import type="com.example.home.data.User" />
<import type="com.examle.detail.data.User" alias="DetailUser" />
<variable name="user" type="DetailUser" />

android:text="@{user.displayName ?? user.lastName}"

android:text="@{user.displayName != null ? user.displayName : user.lastName}"

<TextView
  android:text="@{user.lastName}"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:visibility="@{user.isAdult ? View.VISIBLE : View.GONE}"/>

<TextView
  android:padding="@{large? (int)@dimen/largePadding : (int)@dimen/smallPadding}"
  android:background="@android:color/black"
  android:textColor="@android:color/white"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="@string/hello_world" />