[안드로이드] Data Binding 사용법

DataBinding과 ViewBinding이 뭐가 다른가?
간단하게 말하자면, DataBinding은 이름처럼 데이터를 연결해주는 역할을 할수 있다. (데이터와 같이 결합해서 사용할 수 있음)

이론이 필요한 사람은 ViewBinding vs DataBinding 참고

세팅

build.gradle

android {
	.
	..
    // 추가
    buildFeatures{
        dataBinding = true
    }
}

Activity

xml

<layout></layout> 전체를 감싼다.

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        tools:context=".MainActivity">

        <TextView
            android:id="@+id/dataBindingTextView"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Hello World!"
            android:textSize="50sp" />

    </LinearLayout>

</layout>

MainActivity.kt

class MainActivity : AppCompatActivity() {

    // 1. 추가
    private lateinit var binding : ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        // 2. 추가
        binding = DataBindingUtil.setContentView(this, R.layout.activity_main)

        // 예제 코드
        binding.dataBindingTextView.text = "바뀐 텍스트"

    }
}

Fragment

XML

<layout></layout>으로 전체 레이아웃을 감싼다.

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">
    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".TestFragment">

        <!-- TODO: Update blank fragment layout -->
        <TextView
            android:id="@+id/fragmentText"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:text="@string/hello_blank_fragment"
            android:textSize="50sp" />

    </FrameLayout>
</layout>

Fragment.kt

class TestFragment : Fragment() {

    // 1. 추가
    lateinit var binding: FragmentTestBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

    }

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // 2. 추가
        binding = DataBindingUtil.inflate(inflater, R.layout.fragment_test, container, false)

        // 예제
        binding.fragmentText.text = "변경된 Fragment 텍스트"

        // 3. 추가
        return binding.root
    }

}