Flutter体验—Windows 10环境搭建问题记录

环境信息

• 系统：Windows 10
• 工具：VSCode

准备工作

• 安装最新版 git，注意git需要将http缓存设置大一点，否则sdk拉取失败
• 安装最新版 Android Studio，注意要是最新的
• 安装jdk 17，注意不能是8或11，构建Android时会用到
• 配置全局gradle镜像，或者直接上代理最稳妥

按照官网：开始在 Windows 上构建 Flutter Android 应用 ，用vscode安装flutter。

用vscode创建模板项目，下载flutter sdk，android sdk：

[my_flutter_app] flutter create --template app --overwrite .
Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!
Creating project ....
Resolving dependencies...
Downloading packages...
Got dependencies.
Wrote 129 files.

All done!
You can find general documentation for Flutter at: https://docs.flutter.dev/
Detailed API documentation is available at: https://api.flutter.dev/
If you prefer video documentation, consider: https://www.youtube.com/c/flutterdev

In order to run your application, type:

  $ cd .
  $ flutter run

Your application code is in .\lib\main.dart.

安装检查

先运行一下 flutter doctor --android-licenses

然后执行 flutter doctor -v检查环境

问题1：Could not determine java version

[!] Android toolchain - develop for Android devices (Android SDK version 33.0.1)
    X Could not determine java version

明明已经安装了jdk17，JAVA_HOME和java -version都显示正确，就是找不到java版本，后排查发现装的 Android studio 下面有个 jre 目录，flutter 检测到的java总是指向这个目录。

解决方法：卸载安装最新版本Android studio，再次检测正常。

问题2：Unable to find bundled Java version.

[!] Android Studio (version 4.1)
    • Android Studio at D:\Android\Android Studio
    • Flutter plugin can be installed from:
       https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
       https://plugins.jetbrains.com/plugin/6351-dart
    X Unable to find bundled Java version.
    • Try updating or re-installing Android Studio.

安装最新版本Android studio后发现这一项又检测不到java版本了，搜索得知 flutter 默认找的是 AS下的jre目录中的java，最新版AS没有这个目录，有个jbr
解决方法：将jrb目录发送到桌面快捷方式，然后移动到同目录下，重命名为jre，再次检测正常。

Windows构建

运行flutter run 后，选择 1 ，桌面环境，Windows很容易编译运行成功。

release构建命令

flutter build windows --release

编译过程

E:\Code\Flutter\my_flutter_app>flutter build windows --release 
Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!

Building Windows application...                                    54.1s
√ Built build\windows\x64\runner\Release\my_flutter_app.exe

Android构建

flutter在构建Android包的过程中不显示gradle的构建过程，可能不知道进度或失败在哪里了，可以先用Android studio打开项目下android目录，等依赖下载完成后再用命令行构建。

Android构建命令

flutter build apk --release

过程

E:\Code\Flutter\my_flutter_app>flutter build apk --release
Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!

Flutter assets will be downloaded from https://storage.flutter-io.cn. Make sure you trust this source!
Font asset "MaterialIcons-Regular.otf" was tree-shaken, reducing it from 1645184 to 1384 bytes (99.9% reduction). Tree-shaking can be disabled by providing the --no-tree-shake-icons flag when building your app.
Running Gradle task 'assembleRelease'...                          125.8s
√ Built build\app\outputs\flutter-apk\app-release.apk (17.9MB)

注意：gradle与jdk版本

按 Windows 搭建Flutter开发环境教程 配好gradle全局仓库镜像，执行Android构建，一直报错JDK路径有问题，新建的模板项目默认使用的gradle是8.3.0，必须需要jdk17才行，安装最新jdk后配置环境变量再次尝试。

如果还是JDK版本不对，此时需要给gradle指定jdk版本，在gradle.properties中增加

org.gradle.java.home=D:/Java/jdk-17

android 构建失败时，一般都是依赖包下载不下来，有可能是配置的gradle镜像有问题，最好配置gradle代理，然后用Android studio ，方便排查问题。

配置gradle http代理，还是在gradle.properties中增加

systemProp.http.proxyHost=127.0.0.1
systemProp.http.proxyPort=10809
systemProp.https.proxyHost=127.0.0.1
systemProp.https.proxyPort=10809

如果Android studio中依赖下载完成，一切正常，然后开始运行build，应该没什么大的意外，release版本的安装包只有17M，代理才是最简单的gradle出错解决方法。

常用命令

运行各个平台

flutter run -d windows
flutter run -d macos
flutter run -d linux
flutter run -d android
flutter run -d ios
flutter run -d web