The 'kotlin-android-extensions' Gradle plugin is deprecated

Question

with the Gradle version 6.2 and Android studio version 4.0.1, I have the deprecation message for the Kotlin-android-extention . any body has any idea how to fix it.

Answer 1

It's deprecated Base on the google document

Kotlin Android Extensions is deprecated, which means that using Kotlin synthetics for view binding is no longer supported.

for those who's wonder what the synthetic is. I should say a simple way to access to UI view id with kotlin which was possible by adding 'kotlin-android-extensions' in Gradle .

• If your app uses Parcelable you can use 'kotlin-parcelize' instead of 'kotlin-android-extensions' .
• If your app uses Kotlin synthetics for view binding, use this guide to migrate to Jetpack ViewBinding or Data Binding .

Answer 2

It's deprecated now

• Remove 'Kotlin-android-extention' from the plugin. (Used for kotlin's synthetic way to access UI elements)

• Add below to use view binding way to access UI element

  android {... buildFeatures { viewBinding true } }

• If your app contains Parcelable , please add 'kotlin-parcelize' in plugin to use a simple way to create parcelable by just adding @Parcelize annotation to class

You can see the Google guideline regarding this update.

Answer 3

The above answers are correct, but when you remove 'kotlin-android-extensions' from your project, accessing view properties using kotlin's synthetic way won't be possible, so you need to migrate to use view binding, follow Google's this guide for migrating to view binding: link

Answer 4

As "kotlin-android-extensions" is deprecated now it's better to use view binding.

For this first enable view binding in build.gradle file by writing these line of codes under android block.

buildFeatures {
    viewBinding true
} 

then in activity file to use view binding features

first declare a global variable for binding as

private lateinit var binding:ActivityHomeBinding

Here ActivityHomeBinding is a auto generated class

then write these codes in OnCreate() method

binding = ActivityHomeBinding.inflate(layoutInflater)
setContentView(binding.root)

Answer 5

As already stated, Kotlin Synthetics is deprecated and should be replaced by View Binding. In my case I wanted to introduce View Binding and gradually migrate from Kotlin Synthetics. It's possible to have both in one project, you just need to remember not to update Kotlin version - I had a build error with 4.1.21 , so needed to downgrade to 1.4.10 .

Also remember to delete Kotlin Synthetics imports from a class (usually activity/fragment), which has been migrated to using View Binding.

Answer 6

If the project has huge number of synthetic references and you want to postpone ViewBinding migration as for now, you can use this gradle task to generate Kotlin snythetic code without the "Kotlin android extensions" plugin

https://github.com/sanjeevirajm/kotlin_synthetic_undepreciated

Answer 7

Google privides a new view-binding way instead of 'kotlin-android-extensions'. Adding the following plugins in build.gradle of app module.

android {
...
buildFeatures {
    viewBinding true
}

}

Answer 8

Well, I got this error for a completely different reason. I forgot to add the custom application class where I add hiltannotation in the manifest file.

<application
        android:name=".MyApplication"