今日卸载androidstudio2.3安装androidstudio4.0，安装好4.0创建项目时报错：Connection timed out: connect. If you are behind an HTTP proxy, please configure the proxy setting，与Android Studioand Gradle are using different locations forthe JDK。
1、先解决Android Studioand Gradle are using different locations forthe JDK：
将JDK location改为自己JAVA的JDK安装路径即可。
2、解决Connection timed out: connect. If you are behind an HTTP proxy, please configure the proxy setting：
将v*n连接好后报错：
Could not GET ‘https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.5.3/gradle-3.5.3.pom’. Received status code 400 from server: Bad Request。
解决办法：
断开v*n，将gradle.properties文件中最后四行去掉即可，gradle.properties文件的路径为：C:\Users**.gradle\gradle.properties
保存gradle.properties文件，进入androidstudio进行Sync后项目创建成功！！