🔗【Jetpack】Android ViewBinding 視圖綁定 範例🎯

Android ViewBinding 是 Google 推出的用於便利開發 Android 應用的一種功能，它可以有效簡化訪問 Layout 的繁瑣操作，為開發者提供了更高的表現力和可維護性。

ViewBinding 通過向開發者提供所有 UI 元素的實例來減少代碼的重複量，進而減少與界面連接的時間和精力成本，同時降低崩潰的概率和出錯的可能性。

本文介紹了 Android ViewBinding 的功能、优点以及在框架中的應用，剖析了 ViewBinding 技術對 Android 開發的影響和帶來的優勢。

文章目錄

1. ViewBinding & Fragment KTX 導入
2. ViewBinding Layout
3. ViewBinding MainActivity
4. ViewBinding InflateFragment
5. ViewBinding BindFragment
6. Developer Documents ViewBinding

1.ViewBinding & Fragment KTX 導入

build.gradle

android {

    buildFeatures {
        viewBinding = true
    }
}

dependencies {
    def fragment_version = "1.5.5"
    implementation "androidx.fragment:fragment-ktx:$fragment_version"
}

2.ViewBinding Layout

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    tools:context=".MainActivity">

    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/bind"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintBottom_toTopOf="@+id/guideline3"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/inflate"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/guideline2" />

    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="50sp"
        app:layout_constraintBottom_toTopOf="@+id/guideline2"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/guideline3" />

    <androidx.constraintlayout.widget.Guideline
        android:id="@+id/guideline2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_constraintGuide_percent="0.66" />

    <androidx.constraintlayout.widget.Guideline
        android:id="@+id/guideline3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_constraintGuide_percent="0.33" />

</androidx.constraintlayout.widget.ConstraintLayout>

3.ViewBinding MainActivity

MainActivity.kt

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding

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

        binding = ActivityMainBinding.inflate(layoutInflater)
        binding.name.text = "Activity"
        setContentView(binding.root)
    }

    override fun onStart() {
        super.onStart()

        supportFragmentManager.commit {
            add<BindFragment>(R.id.bind)
            add<InflateFragment>(R.id.inflate)
            setReorderingAllowed(true)
            addToBackStack("name")
        }
    }
}

4.ViewBinding InflateFragment

InflateFragment.kt

class InflateFragment : Fragment() {

    private var fragmentInflateBinding: FragmentInflateBinding? = null

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?,
    ): View {
        val binding = FragmentInflateBinding.inflate(inflater, container, false)
        fragmentInflateBinding = binding
        binding.name.text = "InflateFragment"
        return binding.root
    }

    override fun onDestroyView() {
        fragmentInflateBinding = null
        super.onDestroyView()
    }
}

5.ViewBinding BindFragment

BindFragment.kt

class BindFragment : Fragment(R.layout.fragment_bind) {

    private var fragmentBindBinding: FragmentBindBinding? = null

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        val binding = FragmentBindBinding.bind(view)
        fragmentBindBinding = binding
        binding.name.text = "BindFragment"
    }

    override fun onDestroyView() {
        fragmentBindBinding = null
        super.onDestroyView()
    }
}

6.Developer Documents ViewBinding

Open in Documents ViewBinding