Flutter 错误：无法下载 bcprov-jdk15on.jar (org.bouncycastle:bcprov-jdk15on:1.56)

Question

我无法运行我的第一个 Flutter 应用程序。得到以下错误。

Launching lib\main.dart on Android SDK built for x86 in debug mode...
Initializing gradle...
Resolving dependencies...
* Error running Gradle:
Exit code 1 from: 

D:\PROJECTS\softwareProjects\AndroidProjects\flutter_app_2\android\gradlew.bat 
app:properties:
Download https://jcenter.bintray.com/org/bouncycastle/bcprov-jdk15on/1.56/bcprov-jdk15on-1.56.jar


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 download bcprov-jdk15on.jar (org.bouncycastle:bcprov-jdk15on:1.56)
Finished with error: Please review your Gradle project setup in the android/ folder.
      > Could not get resource 'https://jcenter.bintray.com/org/bouncycastle/bcprov-jdk15on/1.56/bcprov-jdk15on-1.56.jar'.
         > Response 304: Not Modified has no content!

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

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

颤振医生没有给出颤振医生的任何问题输出：

Running flutter doctor...
Doctor summary (to see all details, run flutter doctor -v):
[?] Flutter (Channel beta, v0.1.5, on Microsoft Windows [Version 10.0.16299.309], locale en-IN)
[?] Android toolchain - develop for Android devices (Android SDK 27.0.3)
[?] Android Studio (version 3.0)
[?] Connected devices (1 available)

• No issues found!

不过，颤振分析给出了一些错误！

Answer 1

在发布时，jCenter 在提供某些工件时遇到了问题。这个 gradle 问题跟踪修复的进度，bintray 的状态页面有一个 2018 年 3 月 17 日的条目，详细说明了这个问题。

临时解决方法是使用 mavenCentral 而不是 jCenter（或至少先使用它）。

这可以通过更改 gradle 使用的存储库来完成。由于这是一个 android 项目，因此约定似乎使用 allprojects 如下：

allprojects {
    repositories {
        google()
        mavenCentral()
        jcenter()
    }
}