Flutter报错Flutter和Dart版本问题以及报错curl: (60) SSL certificate

一、Flutter和Dart版本问题

1.Resolving dependencies...
The lower bound of "sdk: '>=2.1.0 <3.0.0'" must be 2.12.0'
or higher to enable null safety.

The current Dart SDK (3.4.3) only supports null safety.

For details, see https://dart.dev/null-safety

2.The current Dart SDK version is 2.19.6.

Because flutter_bili_app requires SDK version >=3.0.0 <4.0.0, version solving failed.
pub get failed
command: "/Users/idol/Documents/Flutter/flutter 3.7.12/bin/cache/dart-sdk/bin/dart __deprecated_pub --directory . get --example"
pub env: {
  "FLUTTER_ROOT": "/Users/idol/Documents/Flutter/flutter 3.7.12",
  "PUB_ENVIRONMENT": "flutter_cli:verify:run",
  "PUB_CACHE": "/Users/idol/.pub-cache",
}
exit code: 1

以上无非是Flutter和Dart版本问题：根据项目情况从以下几种方式入手解决1）在pubspec.yaml理修改environment： sdk:版本范围 2）flutter upgrade 3）如果有安装多个版本的Flutter和SDK可在Setting->Languages & Frameworks 的Dart和Flutter分别选择合适的版本路径

二、curl: (60) SSL certificate problem: self signed certificate in certificate chain

无论在终端flutter doctor还是flutter --version都报错 curl: (60) SSL certificate problem: self signed certificate in certificate chain

解决步骤：在终端输入

curl -k https://storage.flutter-io.cn/flutter_infra_release/flutter/dd93de6fb1776398bf586cbd477deade1391c7e4/dart-sdk-darwin-x64.zip -o dart-sdk-darwin-x64.zip

再输入

export FLUTTER_STORAGE_BASE_URL=https://storage.googleapis.com

最后输入flutter doctor即可