flutter环境安装及各种问题 - Flutter

环境变量

由于在国内访问Flutter有时可能会受到限制，Flutter官方为中国开发者搭建了临时镜像，大家可以将如下环境变量加入到用户环境变量中
Linux设置

export PUB_HOSTED_URL=https://pub.flutter-io.cn
export FLUTTER_STORAGE_BASE_URL=https://storage.flutter-io.cn

Windows设置
在CMD中执行下面两个命令

set PUB_HOSTED_URL=https://pub.flutter-io.cn
set FLUTTER_STORAGE_BASE_URL=https://storage.flutter-io.cn

下载Flutter SDK

官网下载：https://flutter.dev/docs/development/tools/sdk/releases#windows
通过git下载

git clone -b beta https://github.com/flutter/flutter.git

下载之后，windows下设置flutter全局变量=>系统变量=>Path

执行flutter命令

进入flutter SDK代码目录，双击flutter_console.bat，显示如下


         ######## ##       ##     ## ######## ######## ######## ########
         ##       ##       ##     ##    ##       ##    ##       ##     ##
         ##       ##       ##     ##    ##       ##    ##       ##     ##
         ######   ##       ##     ##    ##       ##    ######   ########
         ##       ##       ##     ##    ##       ##    ##       ##   ##
         ##       ##       ##     ##    ##       ##    ##       ##    ##
         ##       ########  #######     ##       ##    ######## ##     ##
 WELCOME to the Flutter Console.
 ================================================================================
 Use the console below this message to interact with the "flutter" command.
 Run "flutter doctor" to check if your system is ready to run Flutter apps.
 Run "flutter create <app_name>" to create a new Flutter project.
 Run "flutter help" to see all available commands.
 Want to use an IDE to interact with Flutter? https://flutter.dev/ide-setup/
 Want to run the "flutter" command from any Command Prompt or PowerShell window?
 Add Flutter to your PATH: https://flutter.dev/setup-windows/#update-your-path
 ================================================================================

执行flutter doctor

D:\project\flutter>flutter doctor
  ╔════════════════════════════════════════════════════════════════════════════╗
  ║                 Welcome to Flutter! - https://flutter.dev                  ║
  ║                                                                            ║
  ║ The Flutter tool anonymously reports feature usage statistics and crash    ║
  ║ reports to Google in order to help Google contribute improvements to       ║
  ║ Flutter over time.                                                         ║
  ║                                                                            ║
  ║ Read about data we send with crash reports:                                ║
  ║ https://github.com/flutter/flutter/wiki/Flutter-CLI-crash-reporting        ║
  ║                                                                            ║
  ║ See Google's privacy policy:                                               ║
  ║ https://www.google.com/intl/en/policies/privacy/                           ║
  ║                                                                            ║
  ║ Use "flutter config --no-analytics" to disable analytics and crash         ║
  ║ reporting.                                                                 ║
  ╚════════════════════════════════════════════════════════════════════════════╝
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.5.4-hotfix.2, on Microsoft Windows [Version 6.1.7601], locale zh-CN)
[X] Android toolchain - develop for Android devices
    X Unable to locate Android SDK.
      Install Android Studio from: https://developer.android.com/studio/index.html
      On first launch it will assist you in installing the Android SDK components.
      (or visit https://flutter.dev/setup/#android-setup for detailed instructions).
      If the Android SDK has been installed to a custom location, set ANDROID_HOME to that location.
      You may also want to add it to your PATH environment variable.
[!] Android Studio (not installed)
[!] VS Code, 64-bit edition
    X Flutter extension not installed; install from
      https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter
[!] Connected device
    ! No devices available
! Doctor found issues in 4 categories.

安装Android Studio

从flutter doctor命令结果中看到，Android Studio没有安装，提提示了安装地址https://developer.android.com/studio/index.html (这个地址需要翻墙)，或者从这个地址下载http://www.android-studio.org/ (不需翻墙)

Android Studio安装不需再多言，按步就班装就可以了

安装好Android Studio后，再次执行flutter doctor

D:\project\flutter>flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.5.4-hotfix.2, on Microsoft Windows [Version 6.1.7601], locale zh-CN)
[!] Android toolchain - develop for Android devices (Android SDK version 29.0.0)
    X Android licenses not accepted.  To resolve this, run: flutter doctor --android-licenses
[!] Android Studio (version 3.4)
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
[!] VS Code, 64-bit edition
    X Flutter extension not installed; install from
      https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter
[!] Connected device
    ! No devices available
! Doctor found issues in 4 categories.

Android licenses

从上一步的提示中，可以看到

Android licenses not accepted.  To resolve this, run: flutter doctor --android-licenses

执行下面命令,一直输入y就好了

flutter doctor --android-licenses

安装Flutter plugin

从上上一步，还可以看到报错

Flutter plugin not installed; this adds Flutter specific functionality.
Dart plugin not installed; this adds Dart specific functionality.

打开Android Studio=>Configure=>Plugins

Dart plugin会和Flutter plugin一起安装，提示时，选择Yes即可

显示下图时，表示Flutter plugin已经安装好了,我们这时就可以创建Flutter项目了

安装vs code 的 Flutter extension

打开https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter
直接安装

再次执行flutter doctor

如下可见，基本的环境已经全部安装好了

D:\project\flutter>flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.5.4-hotfix.2, on Microsoft Windows [Version 6.1.7601], locale zh-CN)
[√] Android toolchain - develop for Android devices (Android SDK version 29.0.0)
[√] Android Studio (version 3.4)
[√] VS Code, 64-bit edition
[!] Connected device
    ! No devices available
! Doctor found issues in 1 category.