Flutter执行flutter build apk时build.gradle报unexpected token错误

错误根因 #

你遇到的构建报错核心是Gradle语法解析失败，具体问题出在build.gradle的defaultConfig代码块：
versionName字段要求传入字符串类型值，你当前写的1.0.0未加引号，被识别为浮点数格式，触发语法错误，间接导致后续android {代码块被判定为非法输入。

修复步骤 #

1. 找到defaultConfig代码块，将versionName 1.0.0修改为versionName "1.0.0"
2. 可选优化：若你使用的Android Gradle插件版本≥7.0，可将buildTypes.release下的useProguard true替换为isMinifyEnabled true，避免废弃参数警告。

修复后完整代码 #

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 GradleException("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"

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

android {
    compileSdkVersion 30

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

    defaultConfig {
        // TODO: Specify your own unique Application ID
        applicationId "com.company.project"
        minSdkVersion 23
        targetSdkVersion 30
        versionCode 1
        versionName "1.0.0"
    }

    signingConfigs {
        release {
            storeFile file('../keystore/key.jks')
            storePassword file('../keystore/keystore.password').text.trim()
            keyPassword file('../keystore/keystore.password').text.trim()
            keyAlias 'key'
        }
    }

    buildTypes {
        release {
            signingConfig signingConfigs.release

            minifyEnabled true
            useProguard true

            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
}

修改完成后重新执行flutter build apk --split-per-abi即可正常构建。

内容的提问来源于stack exchange，提问作者97_HYUN