Gradle (Module:app) Configuration
android {
....
dataBinding {
enabled = true
}
}
Data model
public class Item {
public String name;
public String description;
public Item(String name, String description) {
this.name = name;
this.description = description;
}
}
Layout XML
The first step is wrapping your layout in a <layout>
tag, adding a <data>
element, and adding a <variable>
element for your data model.
Then you can bind XML attributes to fields in the data model using @{model.fieldname}
, where model
is the variable's name and fieldname
is the field you want to access.
item_detail_activity.xml:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable name="item" type="com.example.Item"/>
</data>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{item.name}"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{item.description}"/>
</LinearLayout>
</layout>
For each XML layout file properly configured with bindings, the Android Gradle plugin generates a corresponding class : bindings.
Because we have a layout named item_detail_activity, the corresponding generated binding class is called ItemDetailActivityBinding
.
This binding can then be used in an Activity like so:
public class ItemDetailActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ItemDetailActivityBinding binding = DataBindingUtil.setContentView(this, R.layout.item_detail_activity);
Item item = new Item("Example item", "This is an example item.");
binding.setItem(item);
}
}