如何修复Flutter中‘cannot find symbol’构建失败问题？

刚学习Flutter一周，接手项目时遇到构建失败，错误提示cannot find symbol，无法定位原因。排查后推测是版本不兼容问题，尝试过修改app/build.gradle中的版本配置、切换Flutter频道并升级，也参考过相关解决方案，但都没解决问题。

具体错误表现为：flutter_inappwebview-5.4.3+7库的InAppWebView.java文件中，调用WebSettings的setAppCachePath、setAppCacheEnabled等方法时提示找不到符号。

错误日志 #

user76@user76:~/Documents/Workspace/office/fluter-office(develop)$ flutter run
Using hardware rendering with device Android SDK built for x86. If you notice graphics artifacts, consider enabling software rendering with
"--enable-software-rendering".
Launching lib/main.dart on Android SDK built for x86 in debug mode...
Building with Flutter multidex support enabled.
Warning: Mapping new ns http://schemas.android.com/repository/android/common/02 to old ns http://schemas.android.com/repository/android/common/01
Warning: Mapping new ns http://schemas.android.com/repository/android/generic/02 to old ns http://schemas.android.com/repository/android/generic/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/addon2/02 to old ns http://schemas.android.com/sdk/android/repo/addon2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/addon2/03 to old ns http://schemas.android.com/sdk/android/repo/addon2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/repository2/02 to old ns http://schemas.android.com/sdk/android/repo/repository2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/repository2/03 to old ns http://schemas.android.com/sdk/android/repo/repository2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/sys-img2/03 to old ns http://schemas.android.com/sdk/android/repo/sys-img2/01
Warning: Mapping new ns http://schemas.android.com/sdk/android/repo/sys-img2/02 to old ns http://schemas.android.com/sdk/android/repo/sys-img2/01
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:280: error: cannot find symbol
      settings.setAppCachePath(options.appCachePath);
              ^
  symbol:   method setAppCachePath(String)
  location: variable settings of type WebSettings
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:494: error: cannot find symbol
      settings.setAppCacheEnabled(false);
              ^
  symbol:   method setAppCacheEnabled(boolean)
  location: variable settings of type WebSettings
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:504: error: cannot find symbol
      settings.setAppCacheEnabled(true);
              ^
  symbol:   method setAppCacheEnabled(boolean)
  location: variable settings of type WebSettings
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:515: error: cannot find symbol
        settings.setAppCachePath(ctx.getCacheDir().getAbsolutePath());
                ^
  symbol:   method setAppCachePath(String)
  location: variable settings of type WebSettings
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:517: error: cannot find symbol
        settings.setAppCacheEnabled(true);
                ^
  symbol:   method setAppCacheEnabled(boolean)
  location: variable settings of type WebSettings
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:521: error: cannot find symbol
      settings.setAppCacheEnabled(false);
              ^
  symbol:   method setAppCacheEnabled(boolean)
  location: variable settings of type WebSettings
/home/user76/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_inappwebview-5.4.3+7/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/in_app_webview/InAppWebView.java:767: error: cannot find symbol
      settings.setAppCachePath(newOptions.appCachePath);
              ^
  symbol:   method setAppCachePath(String)
  location: variable settings of type WebSettings
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
7 errors

FAILURE: Build failed with an exception.

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

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 5s
Running Gradle task 'assembleDebug'...                              6.4s
Exception: Gradle task assembleDebug failed with exit code 1

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 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'
}

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

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'

android {
    compileSdkVersion 33

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    kotlinOptions {
        jvmTarget = '1.8'
    }

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

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.wcc.office_app_android"
        minSdkVersion 19
        targetSdkVersion 33
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName

        multiDexEnabled true
    }

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

        debug {
            keyAlias keystoreProperties['keyAlias']
            keyPassword keystoreProperties['keyPassword']
            storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
            storePassword keystoreProperties['storePassword']
        }
    }

    buildTypes {
        release {
            signingConfig signingConfigs.release
        }

        debug {
            signingConfig signingConfigs.debug
        }
    }

    flavorDimensions "environment"
    productFlavors {
        dev {
            dimension "environment"
            applicationIdSuffix ".dev"
            versionNameSuffix "-Dev"
        }

        stag {
            dimension "environment"
            applicationIdSuffix ".stag"
            versionNameSuffix "-Stag"
        }

        prod {
            dimension "environment"
        }
    }

    lintOptions {
        checkReleaseBuilds false
    }
}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation 'com.android.support:multidex:1.0.3'
}

开发环境 #

• Java 18.0.2.1
• Android Studio Chipmunk | 2021.2.1 Patch 1
• Android SDK Build-Tools 33
• Flutter 3.3.0（stable频道）

内容的提问来源于stack exchange，提问作者schutte