Flutter应用升级Gradle 8.0后Release APK构建失败求助

旧版Flutter应用升级Gradle 8.0 + Kotlin 1.8.10后，Debug模式运行正常，但Release APK无法安装，构建过程中出现多轮兼容性错误。

当前android/app/build.gradle配置 #

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new FileNotFoundException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
apply plugin: 'com.google.gms.google-services'
apply plugin: 'com.google.firebase.crashlytics'

def keystoreProperties = new Properties()
def keystorePropertiesFile = rootProject.file('key.properties')
if (keystorePropertiesFile.exists()) {
    keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
}

android {
    compileSdkVersion flutter.compileSdkVersion
    ndkVersion flutter.ndkVersion

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    kotlinOptions {
        jvmTarget = '1.8'
    }

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.example.app"
        minSdkVersion 21
        targetSdkVersion flutter.targetSdkVersion
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }

   signingConfigs {
       release {
           keyAlias keystoreProperties['keyAlias']
           keyPassword keystoreProperties['keyPassword']
           storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
           storePassword keystoreProperties['storePassword']
       }
   }
   buildTypes {
       release {
           signingConfig signingConfigs.release
       }
   }

}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" //1.8.10
    implementation 'com.google.firebase:firebase-core:16.0.9'
//    implementation platform('com.google.firebase:firebase-bom:29.0.4')
    implementation 'com.google.firebase:firebase-analytics'
}

apply plugin: 'com.google.gms.google-services'

首次构建错误信息 #

Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: /Users/llomen/.pub-cache/hosted/pub.dev/firebase_messaging-14.6.9/android/src/main/java/io/flutter/plugins/firebase/messaging/FlutterFirebaseMessagingPlugin.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
Note: /Users/llomen/.pub-cache/hosted/pub.dev/flutter_mailer-2.1.1/android/src/main/java/com/dataxad/flutter_mailer/FlutterMailerPlugin.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
/Users/llomen/.pub-cache/hosted/pub.dev/video_player_android-2.4.10/android/src/main/java/io/flutter/plugins/videoplayer/Messages.java:44: error: pattern matching in instanceof is not supported in -source 8
    if (exception instanceof FlutterError error) {
                                          ^
  (use -source 16 or higher to enable pattern matching in instanceof)
/Users/llomen/.pub-cache/hosted/pub.dev/video_player_android-2.4.10/android/src/main/java/io/flutter/plugins/videoplayer/QueuingEventSink.java:62: error: pattern matching in instanceof is not supported in -source 8
      } else if (event instanceof ErrorEvent errorEvent) {
                                             ^
  (use -source 16 or higher to enable pattern matching in instanceof)
2 errors

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':video_player_android:compileReleaseJavaWithJavac'.
> Compilation failed; see the compiler error output for details.

升级Gradle后的错误信息 #

A problem occurred configuring root project 'android'.
> Could not resolve all files for configuration ':classpath'.
   > Could not resolve com.android.tools.build:gradle:8.0.0.
     Required by:
         project :
      > No matching variant of com.android.tools.build:gradle:8.0.0 was found. The consumer was configured to find a library for use during runtime, compatible with Java 8, packaged as a jar, and its dependencies declared externally, as well as attribute 'org.gradle.plugin.api-version' with value '8.0' but:
          - Variant 'apiElements' capability com.android.tools.build:gradle:8.0.0 declares a library, packaged as a jar, and its dependencies declared externally:
              - Incompatible because this component declares a component for use during compile-time, compatible with Java 11 and the consumer needed a component for use during runtime, compatible with Java 8
              - Other compatible attribute:
                  - Doesn't say anything about org.gradle.plugin.api-version (required '8.0')
          - Variant 'javadocElements' capability com.android.tools.build:gradle:8.0.0 declares a component for use during runtime, and its dependencies declared externally:
              - Incompatible because this component declares documentation and the consumer needed a library
              - Other compatible attributes:
                  - Doesn't say anything about its target Java version (required compatibility with Java 8)
                  - Doesn't say anything about its elements (required them packaged as a jar)
                  - Doesn't say anything about org.gradle.plugin.api-version (required '8.0')
          - Variant 'runtimeElements' capability com.android.tools.build:gradle:8.0.0 declares a library for use during runtime, packaged as a jar, and its dependencies declared externally:
              - Incompatible because this component declares a component, compatible with Java 11 and the consumer needed a component, compatible with Java 8
              - Other compatible attribute:
                  - Doesn't say anything about org.gradle.plugin.api-version (required '8.0')
          - Variant 'sourcesElements' capability com.android.tools.build:gradle:8.0.0 declares a component for use during runtime, and its dependencies declared externally:
              - Incompatible because this component declares documentation and the consumer needed a library
              - Other compatible attributes:
                  - Doesn't say anything about its target Java version (required compatibility with Java 8)
                  - Doesn't say anything about its elements (required them packaged as a jar)
                  - Doesn't say anything about org.gradle.plugin.api-version (required '8.0')

解决方案 #

1. 升级Java版本适配Gradle 8.0 #

Gradle 8.0要求JDK 11及以上，修改android/app/build.gradle的编译配置：

compileOptions {
    sourceCompatibility JavaVersion.VERSION_11
    targetCompatibility JavaVersion.VERSION_11
}

kotlinOptions {
    jvmTarget = '11'
}

同时在Android Studio中设置项目JDK为11（File > Project Structure > SDK Location > JDK Location），本地环境需提前安装JDK 11。

2. 更新Flutter依赖包 #

旧版依赖无法适配新Java语法和Gradle规则，执行命令升级所有依赖：

flutter pub upgrade

若部分依赖升级后仍有问题，直接在pubspec.yaml中指定最新稳定版本，比如video_player、firebase_messaging、flutter_mailer等。

3. 修复Firebase依赖配置 #

移除旧版firebase-core，启用Firebase BOM统一管理版本：

dependencies {
    implementation platform('com.google.firebase:firebase-bom:32.7.1') // 使用最新BOM版本
    implementation 'com.google.firebase:firebase-analytics'
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version" // 适配Kotlin 1.8.10
}

同时删除配置中重复的apply plugin: 'com.google.gms.google-services'。

4. 修正根目录build.gradle配置 #

确保项目根目录的build.gradle（非app模块）中插件版本匹配：

buildscript {
    ext.kotlin_version = '1.8.10'
    repositories {
        google()
        mavenCentral()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:8.0.0'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.gms:google-services:4.4.0'
        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.9.9'
    }
}

5. 清理缓存重新构建 #

执行以下命令清除缓存并重新编译：

flutter clean
flutter pub get
./gradlew clean build

内容的提问来源于stack exchange，提问作者Llomen