kotlin和databinding的一次踩坑

app的gradle 配置以下

apply plugin: 'kotlin-android'

apply plugin: 'kotlin-android-extensions'
...
dependencies {
     ...
     implementation"org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
     ...
}

项目的gradle配置以下

buildscript {
    ext.kotlin_version = '1.2.30'
    ...
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.3'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
}

activity 代码

class MainActivity : MyActivity() {

    private var mBinding: AppActivityMainBinding? = null

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

    private fun init() {
        mBinding = DataBindingUtil.setContentView(this, R.layout.app_activity_main)
    }
}

原本今天开开心心，而后编译报红： :unresolved reference databinding

修改： 在app的gradle里添加

apply plugin: 'kotlin-kapt'
dependencies {
    ...
    kapt "com.android.databinding:compiler:3.1.3"
}

参考文献： https://stackoverflow.com/questions/33165324/kotlin-android-unresolved-reference-databinding