How to add Kotlin Serialization to new Android project?

Question

I'm having a heck of a time adding Kotlin serialization to a new Android project. I'm using Android Studio Chipmunk | 2021.2.1 Patch 2.

When I add the plugin to the project-level build.gradle (see below), I get this sync error:

Build file '/Users/sean/Desktop/code/GradleTest/app/build.gradle' line: 3

An exception occurred applying plugin request [id: 'org.jetbrains.kotlin.android']
> Failed to apply plugin 'org.jetbrains.kotlin.android'.
   > Could not create an instance of type org.jetbrains.kotlin.gradle.dsl.KotlinAndroidProjectExtension.
      > Companion

* Try:

> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Exception is:
org.gradle.api.plugins.InvalidPluginException: An exception occurred applying plugin request [id: 'org.jetbrains.kotlin.android']

Caused by: org.gradle.api.internal.plugins.PluginApplicationException: Failed to apply plugin 'org.jetbrains.kotlin.android'

Caused by: org.gradle.api.reflect.ObjectInstantiationException: Could not create an instance of type org.jetbrains.kotlin.gradle.dsl.KotlinAndroidProjectExtension

Caused by: java.lang.NoSuchFieldError: Companion

Here's the project-level build.gradle where I've attempted to add the plugin:

buildscript {
    ext {
        compose_version = '1.1.0-beta01'
    }
}// Top-level build file where you can add configuration options common to all sub-projects/modules.
plugins {
    id 'com.android.application' version '7.2.2' apply false
    id 'com.android.library' version '7.2.2' apply false
    id 'org.jetbrains.kotlin.android' version '1.5.31' apply false
    id 'org.jetbrains.kotlin.plugin.serialization' version '1.7.10'
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Here's the app module build.gradle which is just the default one that's generated when you create a new project:

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
}

android {
    compileSdk 32

    defaultConfig {
        applicationId "com.sthomas.gradletest"
        minSdk 25
        targetSdk 32
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        vectorDrawables {
            useSupportLibrary true
        }
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
    buildFeatures {
        compose true
    }
    composeOptions {
        kotlinCompilerExtensionVersion compose_version
    }
    packagingOptions {
        resources {
            excludes += '/META-INF/{AL2.0,LGPL2.1}'
        }
    }
}

dependencies {

    implementation 'androidx.core:core-ktx:1.7.0'
    implementation "androidx.compose.ui:ui:$compose_version"
    implementation 'androidx.compose.material3:material3:1.0.0-alpha01'
    implementation "androidx.compose.ui:ui-tooling-preview:$compose_version"
    implementation 'androidx.lifecycle:lifecycle-runtime-ktx:2.3.1'
    implementation 'androidx.activity:activity-compose:1.3.1'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
    androidTestImplementation "androidx.compose.ui:ui-test-junit4:$compose_version"
    debugImplementation "androidx.compose.ui:ui-tooling:$compose_version"
    debugImplementation "androidx.compose.ui:ui-test-manifest:$compose_version"
//    implementation 'org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.2'
}

Here's settings.gradle which is also default:

pluginManagement {
    repositories {
        gradlePluginPortal()
        google()
        mavenCentral()
    }
}
dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
    }
}
rootProject.name = "GradleTest"
include ':app'

Giddy

Answer 1

First step is on build.gradle from project level: You forgot the apply false in front of the version in the plugin line.

plugins {
    id 'org.jetbrains.kotlin.plugin.serialization' version '1.7.10' apply false
}

Second step is on build.gradle from app module: Apply the plugin and add the dependency.

plugins {
    id 'org.jetbrains.kotlin.plugin.serialization'
}

dependencies {
    implementation 'org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.3'
}

With that your project should work, but I would like to draw attention to a possible incompatibility issue if you use different versions of Koltin and Kotlin Plugins. And since you are using Compose, it is necessary to pay attention that the Compiler version of Compose needs to be compatible with the Kotlin version as well and that currently the Compiler version of Compose is no longer linked to versions of other Compose libraries. To know more you can take a look at this link.

So, to improve version compatibility in your project you can do this:

buildscript {
    ext {
        kotlin_ver = '1.7.10'
        compose_compiler_ver = '1.3.0'
        compose_ver = '1.2.1'
    }
}

plugins {
    id 'com.android.application' version '7.2.2' apply false
    id 'com.android.library' version '7.2.2' apply false
    id 'org.jetbrains.kotlin.android' version "$kotlin_ver" apply false
    id 'org.jetbrains.kotlin.plugin.serialization' version "$kotlin_ver" apply false
}

// ...

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
    id 'org.jetbrains.kotlin.plugin.serialization'
}

android {
    // ...

    composeOptions {
        kotlinCompilerExtensionVersion compose_compiler_ver
    }

    // ...
}

dependencies {
    // ...
    implementation "androidx.compose.ui:ui:$compose_ver"
    implementation "androidx.compose.ui:ui-tooling-preview:$compose_ver"

    implementation 'org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.3'

    //...
}

Undemonstrative

Answer 2

If you are using Kotlin DSL then you can follow the below steps add the below code in the level gradle file

id("org.jetbrains.kotlin.plugin.serialization") version "1.7.10" apply false

Go to app level gradle file add the below code in the plugin

plugins {
    id("com.android.application")
..
..
..
    id("org.jetbrains.kotlin.plugin.serialization")
}

add the below dependency in the dependency section

// KotlinX Serialization
implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.2.2")

Promote

what if you're not? – Sokotra

Answer 3

just make the kotlin version "1.9.10" and it will work well

Tropophilous

Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center. – Billmyre