1.首先build.gradle内配置 viewBinding=true 不行试试 viewBinding true

android {
  buildFeatures {
        viewBinding=true
    }
  buildFeatures {
        viewBinding  true
    }
   }

2.如果有些布局文件你不希望为它生成对应的Binding类，可以在该布局文件的根元素位置加入如下声明：

<LinearLayout
    xmlns:tools="http://schemas.android.com/tools"
    ...
    tools:viewBindingIgnore="true">
    ...
</LinearLayout>

3. 查看代码中备注 注意 1.2.3 ActivityMainBinding不是固定是你生成哪个文件就是哪个名字

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding //注意1

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater) //注意2
        setContentView(binding.root) //注意3
        binding.textView.text = "Hello"
    }

}

4.在Fragment中使用ViewBinding
假设我们有一个布局文件叫fragment_main.xml，那么启用ViewBinding功能之后，则必然会生成一个与其对应的FragmentMainBinding类。

class MainFragment : Fragment() {

    private var _binding: FragmentMainBinding? = null

    private val binding get() = _binding!!

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
        _binding = FragmentMainBinding.inflate(inflater, container, false)
        return binding.root
    }

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

}

5.在Adapter中使用ViewBinding
假设我们定义了fruit_item.xml来作为RecyclerView子项的布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="5dp">

    <ImageView
        android:id="@+id/fruitImage"
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="10dp" />

    <TextView
        android:id="@+id/fruitName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="left"
        android:layout_marginTop="10dp" />

</LinearLayout>

然后编写如下RecyclerView Adapter来加载和显示这个子项布局：

class FruitAdapter(val fruitList: List<Fruit>) : RecyclerView.Adapter<FruitAdapter.ViewHolder>() {

    inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
        val fruitImage: ImageView = view.findViewById(R.id.fruitImage)
        val fruitName: TextView = view.findViewById(R.id.fruitName)
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.fruit_item, parent, false)
        return ViewHolder(view)
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val fruit = fruitList[position]
        holder.fruitImage.setImageResource(fruit.imageId)
        holder.fruitName.text = fruit.name
    }

    override fun getItemCount() = fruitList.size

}

6.对引入布局使用ViewBinding include merge

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <include 
        android:id="@+id/titleBar"
        layout="@layout/titlebar" />
    ...
</LinearLayout>

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        binding.titleBar.title.text = "Title"
        binding.titleBar.back.setOnClickListener {
        }
        binding.titleBar.done.setOnClickListener {
        }
    }

}

merge

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

    <Button
        android:id="@+id/back"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true"
        android:text="Back" />

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="Title"
        android:textSize="20sp" />

    <Button
        android:id="@+id/done"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:text="Done" />

</merge>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <include
        layout="@layout/titlebar" />

</LinearLayout>

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding
    private lateinit var titlebarBinding: TitlebarBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        titlebarBinding = TitlebarBinding.bind(binding.root)
        setContentView(binding.root)
        titlebarBinding.title.text = "Title"
        titlebarBinding.back.setOnClickListener {
        }
        titlebarBinding.done.setOnClickListener {
        }
    }

}