Flutter踩坑记录

1 去除Debug 标签

问题：默认创建的Flutter应用运行时，屏幕右上角会带Debug标签
解决：在MyApp的build方法中设置debugShowCheckedModeBanner属性为false。

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      ...
    );
  }
}
...

2 运行程序报错Error connection to the service protocol

Launching lib/main.dart on Android SDK built for x86 in debug mode...
Running Gradle task 'assembleDebug'...
......
Error connecting to the service protocol: failed to connect to http://127.0.0.1:52037/VrXq5vhCjj4=/

解决：

1. 第一种情况，Android模拟器
   坚持自己的模拟器所使用的Android SDK版本，然后通过Tools -> SDKManager 下载匹配的platform版本。
2. 第二种情况，iOS真机。 iOS13.3.1不支持真机调试，但是不影响Release。所以如果是这个版本的真机没法进行调试。

3 Android toolchain 报错

$ flutter doctor 
...
 [!] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
    • Android SDK at /Users/jiafujia/Library/Android/sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-28, build-tools 28.0.3
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b4-5784211)
    ✗ Android license status unknown.
      Try re-installing or updating your Android SDK Manager.
      See https://developer.android.com/studio/#downloads or visit https://flutter.dev/setup/#android-setup for detailed instructions.
...

解决： 通过flutter doctor --android-licenses查看原因，根据提示信息解决。有可

$ flutter doctor --android-licenses

4 iOS无法真机测试

$ flutter upgrade
$ flutter clean
$ flutter build ios

5 iOS模拟器测试报错

Building for iOS Simulator, but the linked and embedded framework 'App.framework' was built for iOS. (in target 'Runner' from project 'Runner')

这是因为真机测试之后，会生成 ios -> Flutter -> App.framework, 而在iOS中构建的真机动态库和模拟器动态库是不一样的。因此我们无法同时在iOS模拟器和真机测试。

在切换iOS真机和模拟器时，我们需要先手动删除 App.framework这个文件夹，然后重新build，如果是真机测试，build方式 flutter build ios. 如果是模拟器如下：

$ flutter devices
    1 connected device:

    iPhone 11 Pro Max • F7B8BFE6-0E23-4777-826F-A132D8A155C2 • ios • com.apple.CoreSimulator.SimRuntime.iOS-13-4 (simulator)

$ flutter run -d F7B

这样就可以在模拟器上进行测试了。

持续更新中...