您的 Flutter 应用程序是使用旧版本的 Android 嵌入创建的

Question

最近我打开了我的旧项目，现在有一个警告说以前没有发生过这样的事情

警告看起来像

Warning
??????????????????????????????????????????????????????????????????????????????
Your Flutter application is created using an older version of the Android
embedding. It's being deprecated in favor of Android embedding v2. Follow the
steps at

https://flutter.dev/go/android-project-migration

to migrate your project.

颤振医生 -v 总结

[?] Flutter (Channel stable, 1.22.2, on Mac OS X 10.15.3 19D76, locale en-GB)
    • Flutter version 1.22.2 at /Users/pkimac/Development/flutter
    • Framework revision 84f3d28555 (6 weeks ago), 2020-10-15 16:26:19 -0700
    • Engine revision b8752bbfff
    • Dart version 2.10.2

 
[?] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
    • Android SDK at /Users/pkimac/Library/Android/sdk
    • Platform android-30, build-tools 29.0.3
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6222593)
    • All Android licenses accepted.

[?] Xcode - develop for iOS and macOS (Xcode 11.3.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 11.3.1, Build version 11C504
    • CocoaPods version 1.10.0.rc.1

[!] Android Studio (version 4.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    ? Flutter plugin not installed; this adds Flutter specific functionality.
    ? Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6222593)

[?] Connected device (1 available)
    • iPhone 11 Pro (mobile) • 7A52F1D0-79F7-471C-AA62-3C106114A1A9 • ios • com.apple.CoreSimulator.SimRuntime.iOS-13-3 (simulator)
    ! Error: Paresh’s iPhone has recently restarted. Xcode will continue when Paresh’s iPhone is unlocked. (code -14)

! Doctor found issues in 1 category.

这是什么意思，我该如何解决这个警告？

Answer 1

如果您在 1.12 版之前创建了项目，则会出现此警告

为了更好地支持将 Flutter 添加到现有项目的执行环境，旧的 Android 平台端包装器托管 Flutter 运行时io.flutter.app.FlutterActivity及其相关类现在已弃用。新的包装器io.flutter.embedding.android.FlutterActivity和相关的类现在取代了它们。

您现有的完整 Flutter 项目不会立即受到影响，并且在可预见的未来将继续像以前一样工作。

要迁移您的项目，请按照以下步骤操作：

1. 删除MainActivity.javaor的正文MainActivity.kt并更改FlutterActivity导入。新的FlutterActivity不再需要手动注册您的插件。它现在将在FlutterEngine创建底层时自动执行注册。你的文件应该是这样的

   package com.appname.app
   
   import io.flutter.embedding.android.FlutterActivity
   
   class MainActivity: FlutterActivity() {
   
   }
   

   如果您有现有的自定义平台，通道处理代码在你MainActivity.java或MainActivity.kt再移动代码的通道注册部分在你的onCreate到的configureFlutterEngine覆盖FlutterActivity子类和使用flutterEngine.getDartExecutor().getBinaryMessenger()的二进制使者，而不是getFlutterView()。

2. 打开 android/app/src/main/AndroidManifest.xml。

3. 从应用程序标签中删除对 FlutterApplication 的引用。你的文件应该是这样的

   以前的配置：

   <application
      android:name="io.flutter.app.FlutterApplication"
      >
      <!-- code omitted -->
   </application>
   

   新配置：

   <application
     >
     <!-- code omitted -->
   </application>
   

4. 更新启动画面行为（如果需要启动画面行为）。

   在AndroidManifest.xml删除所有<meta-data>带有 key 的标签android:name="io.flutter.app.android.SplashScreenUntilFirstFrame"。

5. <meta-data>在 下添加一个新标签<application>。

   <meta-data
     android:name="flutterEmbedding"
     android:value="2" />
   

   

有关更多信息，请参阅：https : //github.com/flutter/flutter/wiki/Upgrading-pre-1.12-Android-projects#full-flutter-app-migration