1. 在app目录下的build.gradle文件中开启viewBinding，开启方式跟DataBinding类似，其中apply plugin: 'kotlin-android-extensions' 是启用绑定机制，跟 ViewBinding 功能类似，都是kotlin自动的

build.gradle

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'  // 启用绑定机制android {compileSdkVersion 30buildToolsVersion "30.0.3"defaultConfig {applicationId "com.example.myviewbinding"minSdkVersion 26targetSdkVersion 30versionCode 1versionName "1.0"testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"// 启动ViewBindingviewBinding {enabled true}// 启动DataBinding/*dataBinding {enabled true}*/}buildTypes {release {minifyEnabled falseproguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'}}}...

  通过gradle插件会生成对应的binding文件，比如布局xml文件名为activity_main.xml，对应生成的binding文件名为ActivityMainBinding

package com.example.myviewbindingimport androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import com.example.myviewbinding.databinding.ActivityMainBinding
// 绑定机制
import kotlinx.android.synthetic.main.activity_main.*class MainActivity : AppCompatActivity() {var vb : ActivityMainBinding ?= nulloverride fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)// 绑定机制/* setContentView(R.layout.activity_main)tv1.text = "AAA"tv2.text = "BBB"*/// ViewBinding 面向对象思想vb = ActivityMainBinding.inflate(layoutInflater)setContentView(vb!!.root)vb!!.tv1.text = "AAA"vb!!.tv2.text = "BBB"}
}

绑定机制的缺点：开发人员可能会在类中导入其他xml布局文件的控件属性，从而导致不易察觉的错误