下载sdk
Flutter SDK releases | Flutter
配置环境变量
export PATH=$PATH:
执行flutter doctor
新建一个命令行窗口，再次输入flutter doctor，仍然报-bash: flutter: command not found这个错误。
全局设置环境变量
open -e .bash_profile
尾部添加
export PATH=${PATH}: + flutter/bin路径
export PUB_HOSTED_URL=https://pub.flutter-io.cn
export FLUTTER_STORAGE_BASE_URL=https://storage.flutter-io.cn
保存，更新环境变量：
source .bash_profile
新建一个窗口，再次输入
flutter doctor
查询版本
flutter -h
flutter --version
dart --version