Android项目Kotlin Serialization插件未生效，如何解决？

我已遵循Kotlin官方文档配置，但仍无法正常使用Kotlin Serialization，使用@Serializable注解时收到如下警告：

kotlinx.serialization compiler plugin is not applied to the module, so this annotation would not be processed. Make sure that you've setup your buildscript correctly and re-import project.

项目级build.gradle配置 #

buildscript {
    ext {
        compose_version = '1.5.5'
        kotlin_version = '1.9.20'
    }
}// Top-level build file where you can add configuration options common to all sub-projects/modules.
plugins {
    id 'com.android.application' version '8.1.4' apply false
    id 'com.android.library' version '8.1.4' apply false
    id 'org.jetbrains.kotlin.android' version "$kotlin_version" apply false
    id 'org.jetbrains.kotlin.plugin.serialization' version "$kotlin_version" apply false
}

测试模块（cannotimportserialization）build.gradle配置 #

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

android {
    namespace 'com.example.cannotimportserialization'
    compileSdk 34

    defaultConfig {
        applicationId "com.example.cannotimportserialization"
        minSdk 29
        targetSdk 34
        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 '1.4.3'
    }
    packaging {
        resources {
            excludes += '/META-INF/{AL2.0,LGPL2.1}'
        }
    }
}

dependencies {

    implementation 'androidx.core:core-ktx:1.9.0'
    implementation 'androidx.lifecycle:lifecycle-runtime-ktx:2.6.2'
    implementation 'androidx.activity:activity-compose:1.8.1'
    implementation platform('androidx.compose:compose-bom:2023.03.00')
    implementation 'androidx.compose.ui:ui'
    implementation 'androidx.compose.ui:ui-graphics'
    implementation 'androidx.compose.ui:ui-tooling-preview'
    implementation 'androidx.compose.material3:material3'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
    androidTestImplementation platform('androidx.compose:compose-bom:2023.03.00')
    androidTestImplementation 'androidx.compose.ui:ui-test-junit4'
    debugImplementation 'androidx.compose.ui:ui-tooling'
    debugImplementation 'androidx.compose.ui:ui-test-manifest'

    implementation "org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.2"
}

项目级settings.gradle配置 #

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

警告截图 #

针对当前配置，按以下步骤修复：

1. 对齐序列化库与Kotlin版本
   Kotlin版本1.9.20对应的序列化库最低版本为1.6.3，当前依赖的1.6.2版本不兼容。修改依赖：

   implementation "org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.3"
   

2. 调整模块插件声明顺序
   将序列化插件放在Kotlin Android插件之前声明，避免加载冲突：

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

3. 清理缓存并同步项目

   • 点击Android Studio右上角的Sync Project with Gradle Files同步项目
   • 执行File > Invalidate Caches... > Invalidate and Restart清理IDE缓存后重启

4. 确认Gradle版本兼容性
   Android Gradle插件8.1.4需要搭配Gradle8.0+版本，检查gradle/wrapper/gradle-wrapper.properties中的配置：

   distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
   

完成以上操作后重新编译项目，@Serializable注解的警告即可消除。

内容的提问来源于stack exchange，提问作者Avin