Data binding for android beginners.

Data binding is a way to bind the UI components like TextView,EditText….. to your code avoiding boiler plate code for initializing every view.

TextView txtView = findViewById(R.id.txtView);

Data binding is a part of JetPack components, allowing a user to make a faster way to program.

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Enabling data binding:

dataBinding{
    enabled = true;
}

Declaring in layout :

There is a mechanism to be implemented to get data binding, now include your layout file inside the

<layout>

    
</layout>

Let’s see a complete instruction

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

<layout>

    <data>

        <variable
            name="User"
            type="com.abhishek.databinding.User" />
    </data>


    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        tools:context=".MainActivity">

        <TextView
            android:id="@+id/name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:padding="10dp"
            android:text="@{User.name}"
            android:textColor="@android:color/black" />

        <TextView
            android:id="@+id/age"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/name"
            android:layout_centerHorizontal="true"
            android:padding="10dp"
            android:text="@{User.age}"
            android:textColor="@android:color/black" />

        <TextView
            android:id="@+id/mobile"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/age"
            android:layout_centerHorizontal="true"
            android:padding="10dp"
            android:text="@{User.mobile}"
            android:textColor="@android:color/black" />

        <TextView
            android:id="@+id/email"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@id/mobile"
            android:layout_centerHorizontal="true"
            android:padding="10dp"
            android:text="@{User.email}"
            android:textColor="@android:color/black" />

    </RelativeLayout>


</layout>

Now the crucial step is to generate a Activity Binding class, is automatically generated if you follow the steps this class is important to deal with data bindings

ActivityMainBinding activityMainBinding;

In your MainActivity class file we need to make use of this file and handle our databinding’s available in that particular layout file.

activityMainBinding = DataBindingUtil.setContentView(this, R.layout.activity_main);

Generate a User model class for accessing the UI objects

public class User {

    public String name;
    public String age;
    public String mobile;
    public String email;
// Getters and Setters
}

Now initialize the class in MainActivity

User user = new User();

Update the details into the Model class

user.setName("Abhishek");
user.setAge("26");
user.setMobile("9876543210");
user.setEmail("abhi@email.com");

then setData to UI components

activityMainBinding.setUser(user);

Advantages

1. Easy to implement and use as well.
2. Faster than implementing findViewById pattern.
3. Reduces boilerplate code.
4. Readability of code is improved.
5. Helpful in testing scenarios.
6. A powerful way to deal with UI components.

For more detailed info visit

http://www.androidcoding.in/2020/02/23/android-data-binding-library-java-jet-pack/