Unresolved reference: BR (Android Studio)

Question

My top level build.gradle:

buildscript {
    ext.kotlin_version = \'1.2.41\'
    ext.lifecycle_version = \"1.1.1\"
    repositories {
        google()
               


        

Answer 1

For Android Studio 3.3, Gradle 3.3.0 and Databinding v2, the only line that needs to be added to fix this issue is in your (app's or modules) build.gradle:

apply plugin: "kotlin-kapt"

Answer 2

Android Studio failed to import my BR class automatically. All solutions provided above failed. I just had to import the class manually, Android studio had created it correctly.

SAMPLE:

package your_packagename

import your_packagename.BR
import ...
...

I think this happened due to Copy and Paste. When i typed BR manually, Android Stdio did the Automatic Import.

Answer 3

I manually typed the line "binding.setVariable(BR.item, item)" and it worked for me. Android studio shows the suggestion of importing BR. Choose the one from your project. Also enable databinding = true in gradle.

Answer 4

After researching quite a bit, turns out there are a couple things to add in order to use data binding library

project build.gradle

buildscript {
    ext {
        compiler_version = '3.1.3'
    }
    dependencies {
        classpath "com.android.tools.build:gradle:$compiler_version"
    }
}

app build.gradle

apply plugin: 'kotlin-kapt'

android {
    dataBinding {
        enabled = true
    }
}

dependencies {
    kapt "com.android.databinding:compiler:$compiler_version"
}

kapt {
    generateStubs = true
}

I started to have some warnings after adding the data binding library, like 3rd-party Gradle plug-ins may be the cause and Classpath entry points to a non-existent location. But compiles and runs fine