一、下载并安装Maven

1.下载

下载地址：https://maven.apache.org/download.cgi ，浏览器打开链接下载最新的3.9.11版本

bash
flutter pub cache clean

flutter doctor 出现：

bash
[!] Network resources
    X A network error occurred while checking "https://github.com/": 信号灯超时时间已到

flutter打包时报错：

bash
Execution failed for task ':xxx:verifyReleaseResources'.
> A failure occurred while executing com.android.build.gradle.tasks.VerifyLibraryResourcesTask$Action
   > Android resource linking failed
     ERROR: D:\Project\apprheofit-china\app_rheofit\build\cloudbase_ce\intermediates\merged_res\release\mergeReleaseResources\values\values.xml:194: AAPT: error: resource android:attr/lStar not found.

运行flutter pub get时提示：

bash
Building with plugins requires symlink support.

Please enable Developer Mode in your system settings. Run
  start ms-settings:developers
to open settings.
exit code 1