docs: fix escaped characters in data binding doc am: 011c07bd

</pre>

<p>

  Expressions within the layout are written in the attribute properties using

  the “<code>&amp;commat;{}</code>” syntax. Here, the TextView’s text is set to

  the "<code>&commat;{}</code>" syntax. Here, the TextView's text is set to

  the firstName property of user:

</p>

<pre>

<TextView android:layout_width="wrap_content"

          android:layout_height="wrap_content"

          android:text="@{user.firstName}"/>

          android:text="@{user.firstName}"/>

</pre>

<h3 id="data_object">

  Data Object

</h3>

<p>

  Let’s assume for now that you have a plain-old Java object (POJO) for User:

  Let's assume for now that you have a plain-old Java object (POJO) for User:

</p>

<pre>

</pre>

<p>

  From the perspective of data binding, these two classes are equivalent. The

  expression <strong><code>&amp;commat;{user.firstName}</code></strong> used

  for the TextView’s <strong><code>android:text</code></strong> attribute will

  expression <strong><code>&commat;{user.firstName}</code></strong> used

  for the TextView's <strong><code>android:text</code></strong> attribute will

  access the <strong><code>firstName</code></strong> field in the former class

  and the <code>getFirstName()</code> method in the latter class.

  Alternatively, it will also be resolved to <code>firstName()</code> if that

<p>

  By default, a Binding class will be generated based on the name of the layout

  file, converting it to Pascal case and suffixing “Binding” to it. The above

  file, converting it to Pascal case and suffixing "Binding" to it. The above

  layout file was <code>main_activity.xml</code> so the generate class was

  <code>MainActivityBinding</code>. This class holds all the bindings from the

  layout properties (e.g. the <code>user</code> variable) to the layout’s Views

  layout properties (e.g. the <code>user</code> variable) to the layout's Views

  and knows how to assign values for the binding expressions.The easiest means

  for creating the bindings is to do it while inflating:

</p>

}

</pre>

<p>

  You’re done! Run the application and you’ll see Test User in the UI.

  You're done! Run the application and you'll see Test User in the UI.

  Alternatively, you can get the view via:

</p>

</pre>

  Then you can bind the click event to your class as follows:

<pre>

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

  <layout xmlns:android="http://schemas.android.com/apk/res/android">

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

  <layout xmlns:android="http://schemas.android.com/apk/res/android">

      <data>

          <variable name="task" type="com.android.example.Task" />

          <variable name="presenter" type="com.android.example.Presenter" />

          <variable name="task" type="com.android.example.Task" />

          <variable name="presenter" type="com.android.example.Presenter" />

      </data>

      <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent">

          <Button android:layout_width="wrap_content" android:layout_height="wrap_content"

          android:onClick="@{() -> presenter.onSaveClick(task)}" />

      <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent">

          <Button android:layout_width="wrap_content" android:layout_height="wrap_content"

          android:onClick="@{() -> presenter.onSaveClick(task)}" />

      </LinearLayout>

  </layout>

</pre>

  above could be written as:

</p>

<pre>

  android:onClick="@{(view) -> presenter.onSaveClick(task)}"

  android:onClick="@{(view) -> presenter.onSaveClick(task)}"

</pre>

Or if you wanted to use the parameter in the expression, it could work as follows:

<pre>

}

</pre>

<pre>

  android:onClick="@{(theView) -> presenter.onSaveClick(theView, task)}"

  android:onClick="@{(theView) -> presenter.onSaveClick(theView, task)}"

</pre>

You can use a lambda expression with more than one parameter:

<pre>

}

</pre>

<pre>

  <CheckBox android:layout_width="wrap_content" android:layout_height="wrap_content"

        android:onCheckedChanged="@{(cb, isChecked) -> presenter.completeChanged(task, isChecked)}" />

  <CheckBox android:layout_width="wrap_content" android:layout_height="wrap_content"

        android:onCheckedChanged="@{(cb, isChecked) -> presenter.completeChanged(task, isChecked)}" />

</pre>

<p>

  If the event you are listening to returns a value whose type is not {@code

}

</pre>

<pre>

  android:onLongClick="@{(theView) -> presenter.onLongClick(theView, task)}"

  android:onLongClick="@{(theView) -> presenter.onLongClick(theView, task)}"

</pre>

<p>

If the expression cannot be evaluated due to {@code null} objects, Data Binding returns

{@code void} as a symbol.

</p>

<pre>

  android:onClick="@{(v) -> v.isVisible() ? doSomething() : void}"

  android:onClick="@{(v) -> v.isVisible() ? doSomething() : void}"

</pre>

<h5>Avoid Complex Listeners</h5>

</pre>

<p>

  When there are class name conflicts, one of the classes may be renamed to an

  “alias:”

  "alias:"

</p>

<pre>

    <import type="com.example.User"/>

    <import type="java.util.List"/>

    <variable name="user" type="User"/>

    <variable name="userList" type="List<User>"/>

    <variable name="userList" type="List<User>"/>

</data>

</pre>

<p class="caution">

<p>

  By default, a Binding class is generated based on the name of the layout

  file, starting it with upper-case, removing underscores ( _ ) and

  capitalizing the following letter and then suffixing “Binding”. This class

  capitalizing the following letter and then suffixing "Binding". This class

  will be placed in a databinding package under the module package. For

  example, the layout file <code>contact_item.xml</code> will generate

  <code>ContactItemBinding</code>. If the module package is

  This generates the binding class as <code>ContactItem</code> in the

  databinding package in the module package. If the class should be generated

  in a different package within the module package, it may be prefixed with

  “.”:

  ".":

</p>

<pre>

</h3>

<p>

  Variables may be passed into an included layout's binding from the

  Variables may be passed into an included layout's binding from the

  containing layout by using the application namespace and the variable name in

  an attribute:

</p>

<pre>

android:text="@{String.valueOf(index + 1)}"

android:visibility="@{age < 13 ? View.GONE : View.VISIBLE}"

android:transitionName='@{"image_" + id}'

android:visibility="@{age < 13 ? View.GONE : View.VISIBLE}"

android:transitionName='@{"image_" + id}'

</pre>

<h4 id="missing_operations">

  Missing Operations

    <import type="android.util.SparseArray"/>

    <import type="java.util.Map"/>

    <import type="java.util.List"/>

    <variable name="list" type="List<String>"/>

    <variable name="sparse" type="SparseArray<String>"/>

    <variable name="map" type="Map<String, String>"/>

    <variable name="list" type="List<String>"/>

    <variable name="sparse" type="SparseArray<String>"/>

    <variable name="map" type="Map<String, String>"/>

    <variable name="index" type="int"/>

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

</data>

</p>

<pre>

android:text='@{map["firstName"]}'

android:text='@{map["firstName"]}'

</pre>

<p>

  It is also possible to use double quotes to surround the attribute value.

  When doing so, String literals should either use the " or back quote

  When doing so, String literals should either use the ' or back quote

  (`).

</p>

<pre>

android:text="@{map[`firstName`}"

android:text="@{map["firstName"]}"

android:text="@{map['firstName']}"

</pre>

<h4 id="resources">

  Resources

}

</pre>

<p>

  That's it! To access the value, use the set and get accessor methods:

  That's it! To access the value, use the set and get accessor methods:

</p>

<pre>

<pre>

<data>

    <import type="android.databinding.ObservableMap"/>

    <variable name="user" type="ObservableMap<String, Object>"/>

    <variable name="user" type="ObservableMap<String, Object>"/>

</data>

…

<TextView

   android:text='@{user["lastName"]}'

   android:text='@{user["lastName"]}'

   android:layout_width="wrap_content"

   android:layout_height="wrap_content"/>

<TextView

   android:text='@{String.valueOf(1 + (Integer)user["age"])}'

   android:text='@{String.valueOf(1 + (Integer)user["age"])}'

   android:layout_width="wrap_content"

   android:layout_height="wrap_content"/>

</pre>

<data>

    <import type="android.databinding.ObservableList"/>

    <import type="com.example.my.app.Fields"/>

    <variable name="user" type="ObservableList<Object>"/>

    <variable name="user" type="ObservableList<Object>"/>

</data>

…

<TextView

   android:text='@{user[Fields.LAST_NAME]}'

   android:text='@{user[Fields.LAST_NAME]}'

   android:layout_width="wrap_content"

   android:layout_height="wrap_content"/>

<TextView

   android:text='@{String.valueOf(1 + (Integer)user[Fields.AGE])}'

   android:text='@{String.valueOf(1 + (Integer)user[Fields.AGE])}'

   android:layout_width="wrap_content"

   android:layout_height="wrap_content"/>

</pre>

<p>

  When inflating another layout, a binding must be established for the new

  layout. Therefore, the <code>ViewStubProxy</code> must listen to the <code>ViewStub</code>&apos;s

  layout. Therefore, the <code>ViewStubProxy</code> must listen to the <code>ViewStub</code>'s

  {@link android.view.ViewStub.OnInflateListener} and establish the binding at that time. Since

  only one can exist, the <code>ViewStubProxy</code> allows the developer to set an

  <code>OnInflateListener</code> on it that it will call after establishing the binding.

</h4>

<p>

  At times, the specific binding class won't be known. For example, a

  At times, the specific binding class won't be known. For example, a

  {@link android.support.v7.widget.RecyclerView.Adapter} operating against arbitrary layouts

  won't know the specific binding class. It still must assign the binding value during the

  won't know the specific binding class. It still must assign the binding value during the

  {@link android.support.v7.widget.RecyclerView.Adapter#onBindViewHolder}.

</p>

For an attribute, data binding tries to find the method setAttribute. The

namespace for the attribute does not matter, only the attribute name itself.

<p>

  For example, an expression associated with TextView's attribute

  For example, an expression associated with TextView's attribute

  <strong><code>android:text</code></strong> will look for a setText(String).

  If the expression returns an int, data binding will search for a setText(int)

  method. Be careful to have the expression return the correct type, casting if

  necessary. Note that data binding will work even if no attribute exists with

  the given name. You can then easily "create" attributes for any setter by

  using data binding. For example, support DrawerLayout doesn't have any

  using data binding. For example, support DrawerLayout doesn't have any

  attributes, but plenty of setters. You can use the automatic setters to use

  one of these.

</p>

</h3>

<p>

  Some attributes have setters that don't match by name. For these

  Some attributes have setters that don't match by name. For these

  methods, an attribute may be associated with the setter through

  {@link android.databinding.BindingMethods} annotation. This must be associated with

  a class and contains {@link android.databinding.BindingMethod} annotations, one for

}

</pre>

<pre>

<ImageView app:imageUrl=“@{venue.imageUrl}”

app:error=“@{@drawable/venueError}”/>

<ImageView app:imageUrl="@{venue.imageUrl}"

app:error="@{@drawable/venueError}"/>

</pre>

<p>

<pre>

<TextView

   android:text='@{userMap["lastName"]}'

   android:text='@{userMap["lastName"]}'

   android:layout_width="wrap_content"

   android:layout_height="wrap_content"/>

</pre>