Could not find io.flutter:flutter_embedding_debug

flutter SDK 及Android Studio插件的安装都是参照flutter的介绍和环境搭建（超详细）来进行的，flutter doctor一切正常。但新建flutter project后，运行就卡住了。

备注：

Dart version 2.8.2

Android Studio (version 3.6)

Flutter version 1.17.1


Running Gradle task 'assembleDebug'...    
This is taking an unexpectedly long time.

运行时会卡在Running Gradle task ‘assembleDebug’…, 因为Gradle的Maven仓库在国外, 可以使用阿里云的镜像地址。

具体报错如下，环境什么的都OK

* What went wrong:
Execution failed for task ':flutter:javaPreCompileDebug'.
> Could not resolve all files for configuration ':flutter:debugCompileClasspath'.
   > Could not find io.flutter:flutter_embedding_debug:1.0.0-5b952f286fc070e99cf192775fa5c9dfe858b692.
     Required by:
         project :flutter
   > Could not find io.flutter:arm64_v8a_debug:1.0.0-5b952f286fc070e99cf192775fa5c9dfe858b692.
     Required by:
         project :flutter
   > Could not find io.flutter:x86_debug:1.0.0-5b952f286fc070e99cf192775fa5c9dfe858b692.
     Required by:
         project :flutter
   > Could not find io.flutter:x86_64_debug:1.0.0-5b952f286fc070e99cf192775fa5c9dfe858b692.
     Required by:
         project :flutter

环境如下

[√] Flutter (Channel stable, v1.17.1, on Microsoft Windows [Version 10.0.18362.836], locale zh-CN)
    • Flutter version 1.17.1 at D:\SoftWare\Java\flutter
    • Framework revision f7a6a7906b (7 days ago), 2020-05-12 18:39:00 -0700
    • Engine revision 6bc433c6b6
    • Dart version 2.8.2


[!] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
    • Android SDK at D:\SoftWare\Java\Android\Sdk
    • Platform android-29, build-tools 29.0.2
    • ANDROID_HOME = D:\SoftWare\Java\Android\Sdk
    • Java binary at: D:\SoftWare\Java\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b04)
    ! Some Android licenses not accepted.  To resolve this, run: flutter doctor --android-licenses

[√] Android Studio (version 3.6)
    • Android Studio at D:\SoftWare\Java\Android\Android Studio
    • Flutter plugin version 45.1.1
    • Dart plugin version 192.8052
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b04)

[!] IntelliJ IDEA Ultimate Edition (version 2019.2)
    • IntelliJ at D:\SoftWare\Java\IntelliJ IDEA
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
    • For information about installing plugins, see
      https://flutter.dev/intellij-setup/#installing-the-plugins

[√] Connected device (1 available)
    • Redmi 6 • 150496647d2a • android-arm • Android 9 (API 28)

! Doctor found issues in 2 categories.

第一种解决办法：

在flutterSDK文件目录打开这个文件 flutter/packages/flutter_tools/gradle/resolve_dependencies.gradle添加

repositories {
    google()
    jcenter()
    maven {
        url "https://storage.proxy.ustclug.org/download.flutter.io"
    }
	maven {
            url 'http://download.flutter.io'
    }
}

添加库

maven {
    url 'http://download.flutter.io'
}

第二种就是在本地项目：

        //应用下面maven远程仓库
        //google()
        //jcenter()
        maven { url 'https://maven.aliyun.com/repository/google' }
        maven { url 'https://maven.aliyun.com/repository/jcenter' }
        maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }
        maven {
            url 'http://download.flutter.io'
        }

或者采用第三种下面的方法：Flutter Maven repository should support HTTPS

Could not find io.flutter:flutter_embedding_debug

flutter\packages\flutter_tools\gradle 目录下面的文件夹 flutter.gradle文件 MAVEN_REPO修改maven远程仓库修改

    //private static final String MAVEN_REPO      = "https://storage.proxy.ustclug.org/download.flutter.io";
    private static final String MAVEN_REPO      = "http://download.flutter.io";//修改之后

Could not find io.flutter:flutter_embedding_debug