执行npx cap run android时Android根项目配置失败求助

我折腾了好几个小时，排查错误日志、更换Gradle版本、切换不同Java SDK、清理重建项目，全都没用。这是个全新的Ionic+Vue项目，所有版本都是最新的，Android Studio也更到最新了。用Android Studio启动的话，不管是模拟器还是真机都能正常跑，但我想用npx cap run android命令启动，结果报错了。

报错信息 #

PS C:\custom\dev\ionic\app> npx cap run android --scan 
√ Copying web assets from dist to android\app\src\main\assets\public in 46.16ms
√ Creating capacitor.config.json in android\app\src\main\assets in 1.20ms
[info] Inlining sourcemaps
√ copy android in 78.40ms
√ Updating Android plugins in 3.79ms
[info] Found 6 Capacitor plugins for android:
       @capacitor/app@5.0.6
       @capacitor/camera@5.0.7
       @capacitor/geolocation@5.0.6
       @capacitor/haptics@5.0.6
       @capacitor/keyboard@5.0.6
       @capacitor/status-bar@5.0.6
√ update android in 68.46ms
√ Please choose a target device: » Pixel 2 API 30 (emulator) (Pixel_2_API_30)
× Running Gradle build - failed!
[error]
        FAILURE: Build failed with an exception.

        * What went wrong:
        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 '8.0.2' 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 '8.0.2')
        - 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 '8.0.2')
        - 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 '8.0.2')
        - 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 '8.0.2')

        * 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 761ms

核心问题是Gradle插件8.0.0要求Java 11运行环境，但你的命令行用的是Java 8——Android Studio能正常跑是因为它自带了适配的JDK，命令行环境没同步配置。

按以下步骤处理：

• 检查并切换Java版本
  打开命令行输入java -version，如果显示Java 8，安装Java 11（OpenJDK或Oracle JDK均可），然后把JAVA_HOME环境变量指向Java 11的安装目录，同时将%JAVA_HOME%\bin（Windows）或$JAVA_HOME/bin（Mac/Linux）加入系统Path。

• 复用Android Studio的JDK（快捷方案）
  打开Android Studio，依次进入File → Project Structure → SDK Location，复制显示的JDK路径，直接把命令行的JAVA_HOME设为这个路径，避免重新安装。

• 同步项目配置并重建
  在项目根目录执行以下命令：

  npx cap clean android
  npm run build
  npx cap sync android
  npx cap run android
  

内容的提问来源于stack exchange，提问作者narrei