Android Studio升级到gradle 7.0时遇到的若干问题

我们使用阿里镜像去下载库，升级到7.0时会出现以下错误：

opt-in, is unsupported. Switch Maven repository 
'maven(http://maven.aliyun.com/nexus/content/groups/public/)' to redirect to a secure 
protocol (like HTTPS) or allow insecure protocols.

解决办法：在项目的build.gradle中加入allowInsecureProtocol = true，如下：

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
    repositories {
        maven {
            url 'http://maven.aliyun.com/nexus/content/groups/public/'
            allowInsecureProtocol true
        }
        google()
        jcenter()
        mavenCentral()
        maven { url 'https://jitpack.io' }
        maven { url 'https://dl.bintray.com/youzanyun/maven/' }
        maven {
            url 'http://developer.huawei.com/repo/'
            allowInsecureProtocol true
        }
        maven { url 'https://dl.bintray.com/umsdk/release' }
    }
}

allprojects {
    repositories {
        maven {
            url 'http://maven.aliyun.com/nexus/content/groups/public/'
            allowInsecureProtocol true
        }
        google()
        jcenter()
        mavenCentral()
        maven { url 'https://jitpack.io' }
        maven {
            url 'http://developer.huawei.com/repo/'
            allowInsecureProtocol true
        }
        maven { url 'https://dl.bintray.com/umsdk/release' }
    }
}