一.命令

创建flutter项目 flutter create
运行flutter项目 在项目的根目录flutter run -d 'iPhone X

二.运行报错

找到android目录下build.gradle,将google的源替换下

//        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' }
    }

进入/Users/LYK/lykFlutter/flutter/packages/flutter_tools/gradle/flutter.gradle修改

buildscript {
    repositories {
        //jcenter()
        // maven {
        //     url 'https://dl.google.com/dl/android/maven2'
        // }
        maven{
            url 'https://maven.aliyun.com/repository/jcenter'
        }
        maven{
            url 'http://maven.aliyun.com/nexus/content/groups/public'
        }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
    }
}

然后再重新Debug一下，就基本可以启动起来。