我刚开始使用Flutter开发应用程序，但甚至无法运行测试应用程序。这就是控制台上的内容：
Launching lib/main.dart on AOSP on IA Emulator in debug mode... Running Gradle task 'assembleDebug'... Exception in thread "main" java.util.zip.ZipException: error in opening zip file at java.util.zip.ZipFile.open(Native Method) at java.util.zip.ZipFile.(ZipFile.java:225) at java.util.zip.ZipFile.(ZipFile.java:155) at java.util.zip.ZipFile.(ZipFile.java:169) at org.gradle.wrapper.Install.unzip(Install.java:214) at org.gradle.wrapper.Install.access$600(Install.java:27) at org.gradle.wrapper.Install$1.call(Install.java:74) at org.gradle.wrapper.Install$1.call(Install.java:48) at org.gradle.wrapper.ExclusiveFileAccessManager.access(ExclusiveFileAccessManager.java:65) at org.gradle.wrapper.Install.createDist(Install.java:48) at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:128) at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61) [!] Gradle threw an error while downloading artifacts from the network. Retrying to download...
我有有效的Internet连接。我还下载了gradle 6.4.1并将其提取到android-studio >>插件中，此内容已在gradle-wrapper.properties中显示：
distributionBase=GRADLE_USER_HOME distributionPath=wrapper/dists zipStoreBase=GRADLE_USER_HOME zipStorePath=wrapper/dists distributionUrl=https://services.gradle.org/distributions/gradle-5.6.2-all.zip*
我使用Ubuntu 18.04。
我正在运行macOS，因此在Flutter build之前，我添加了sudo flutter build，这使Gradle 6的下载工作正常