一个flutter项目，其实也不是太老，主要是flutter升级的太快，新同事加载flutter项目时，总会遇到这样那样奇奇怪怪的问题，这里记录一下，希望能帮到遇到同样困难的其他同学。

1. 在ios目录下，执行 pod install --clean-install 后，出现架包错误；
错误如下图所示：

Analyzing dependencies
[!] CocoaPods could not find compatible versions for pod "AgoraRtcEngine_iOS":
  In snapshot (Podfile.lock):
    AgoraRtcEngine_iOS (= 3.4.6)
  In Podfile:
    agora_rtc_engine (from `.symlinks/plugins/agora_rtc_engine/ios`) was resolved to 4.0.7, which depends on
      AgoraRtcEngine_iOS (= 3.5.0.3)
You have either:
 * out-of-date source repos which you can update with `pod repo update` or with `pod install --repo-update`.
 * changed the constraints of dependency `AgoraRtcEngine_iOS` inside your development pod `agora_rtc_engine`.
   You should run `pod update AgoraRtcEngine_iOS` to apply changes you've made.
[!] Automatically assigning platform `iOS` with version `12.0` on target `Runner` because no platform was specified. Please specify a platform for this target in your Podfile. See `[https://guides.cocoapods.org/syntax/podfile.html#platform](https://guides.cocoapods.org/syntax/podfile.html#platform)`.

2.根据提示信息，输入命令：pod install --repo-update
命令输入后，依旧报错，错误信息如下图所示：

Updating local specs repositories
  $ /usr/bin/git -C /Users/ioskaifa110/.cocoapods/repos/cocoapods fetch origin --progress
  remote: Enumerating objects: 16015, done.        
  remote: Counting objects: 100% (6919/6919), done. 
  remote: Compressing objects: 100% (227/227), done.       
  error: RPC failed; curl 56 LibreSSL SSL_read: SSL_ERROR_SYSCALL, errno 54
  error: 3334 bytes of body are still expected
  fetch-pack: unexpected disconnect while reading sideband packet
  fatal: early EOF
  fatal: index-pack failed
[!] CocoaPods was not able to update the `cocoapods` repo. If this is an unexpected issue and persists you can inspect it running `pod repo update --verbose`

3.依旧报错，根据提示输入命令：pod repo update --verbose

  CDN: trunk Relative path: CocoaPods-version.yml exists! Returning local because checking is only performed in repo update
Updating spec repo `aliyun-aliyun-specs`
Updating spec repo `cocoapods`
  $ /usr/bin/git -C /Users/ioskaifa110/.cocoapods/repos/cocoapods fetch origin --progress
  fatal: unable to access '[https://github.com/CocoaPods/Specs.git/](https://github.com/CocoaPods/Specs.git/)': LibreSSL SSL_connect: SSL_ERROR_SYSCALL in connection to github.com:443
[!] CocoaPods was not able to update the `cocoapods` repo. If this is an unexpected issue and persists you can inspect it running `pod repo update --verbose`
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:187:in `rescue in update_git_repo'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:178:in `update_git_repo'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-core-1.11.2/lib/cocoapods-core/source.rb:354:in `update'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:144:in `block (3 levels) in update'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/user_interface.rb:64:in `section'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:143:in `block (2 levels) in update'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:142:in `each'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:142:in `block in update'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:140:in `open'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/sources_manager.rb:140:in `update'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/command/repo/update.rb:23:in `run'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/claide-1.0.3/lib/claide/command.rb:334:in `run'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/lib/cocoapods/command.rb:52:in `run'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/gems/cocoapods-1.11.2/bin/pod:55:in `<top (required)>'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/bin/pod:23:in `load'
/usr/local/Cellar/cocoapods/1.11.2_1/libexec/bin/pod:23:in `<main>'

4.依旧报错，根据提示，再来一次：pod repo update --verbose

  CDN: trunk Relative path: CocoaPods-version.yml exists! Returning local because checking is only performed in repo update
Updating spec repo `aliyun-aliyun-specs`
Updating spec repo `cocoapods`
  $ /usr/bin/git -C /Users/ioskaifa110/.cocoapods/repos/cocoapods fetch origin --progress
  remote: Enumerating objects: 16048, done.     
  remote: Counting objects: 100% (6974/6974), done.        
  remote: Compressing objects: 100% (199/199), done.       
  remote: Total 16048 (delta 6769), reused 6950 (delta 6762), pack-reused 9074          Receiving objects: 100% (16048/16048), 2.43 MiB | 3.54 MiB/s, done.
  Resolving deltas: 100% (11033/11033), completed with 2320 local objects.
  From [https://github.com/CocoaPods/Specs](https://github.com/CocoaPods/Specs)
     bcfb480b2a7b..babb3cec1793  master     -> origin/master
  $ /usr/bin/git -C /Users/ioskaifa110/.cocoapods/repos/cocoapods rev-parse --abbrev-ref HEAD
  master
  $ /usr/bin/git -C /Users/ioskaifa110/.cocoapods/repos/cocoapods reset --hard origin/master
  HEAD is now at babb3cec1793 [Add] AliInteractiveDocumentCore 1.5.0-rc8
Updating spec repo `trunk`
  CDN: trunk Relative path downloaded: deprecated_podspecs.txt, save ETag: W/"61bc05f6-8987f"
  CDN: trunk Going to update 13 files
  CDN: trunk Relative path: all_pods_versions_1_1_7.txt, has ETag? W/"61bbfe1a-9b9"
  CDN: trunk Relative path: all_pods_versions_5_d_c.txt, has ETag? W/"61bbfe1a-495"
  CDN: trunk Relative path: all_pods_versions_1_d_9.txt, has ETag? W/"61bc040d-8a7"
  CDN: trunk Relative path: all_pods_versions_e_9_d.txt, has ETag? W/"61bbfe1a-4d8"
  CDN: trunk Relative path: all_pods_versions_b_2_d.txt, has ETag? W/"61b6ff40-57c"
  CDN: trunk Relative path: all_pods_versions_1_6_1.txt, has ETag? W/"61bc040d-475"
  CDN: trunk Relative path: all_pods_versions_3_7_4.txt, has ETag? W/"61bbfe1a-464"
  CDN: trunk Relative path: all_pods_versions_6_f_0.txt, has ETag? W/"61bbfe1a-34a"
  CDN: trunk Relative path: CocoaPods-version.yml, has ETag? "61b6ff40-38"
  CDN: trunk Relative path: all_pods_versions_c_7_9.txt, has ETag? W/"61bbfe1a-50d"
  CDN: trunk Relative path: all_pods_versions_3_7_9.txt, has ETag? W/"61b6ff40-417"
  CDN: trunk Relative path: all_pods_versions_f_4_e.txt, has ETag? W/"61bc040d-4bb"
  CDN: trunk Relative path: all_pods_versions_1_9_2.txt, has ETag? W/"61bc040d-1bb"
  CDN: trunk Relative path downloaded: all_pods_versions_1_1_7.txt, save ETag: W/"61bc07cd-9b9"
  CDN: trunk Relative path downloaded: all_pods_versions_1_d_9.txt, save ETag: W/"61bc05f5-8a7"
  CDN: trunk Relative path downloaded: all_pods_versions_1_6_1.txt, save ETag: W/"61bc05f5-475"
  CDN: trunk Relative path downloaded: all_pods_versions_e_9_d.txt, save ETag: W/"61bc05f5-4d8"
  CDN: trunk Relative path downloaded: all_pods_versions_5_d_c.txt, save ETag: W/"61bc05f5-495"
  CDN: trunk Relative path downloaded: all_pods_versions_f_4_e.txt, save ETag: W/"61bc05f5-4bb"
  CDN: trunk Relative path downloaded: all_pods_versions_b_2_d.txt, save ETag: W/"61bc07cd-57c"
  CDN: trunk Relative path downloaded: all_pods_versions_3_7_9.txt, save ETag: W/"61bc07cd-417"
  CDN: trunk Relative path downloaded: all_pods_versions_3_7_4.txt, save ETag: W/"61bc05f5-464"
  CDN: trunk Relative path downloaded: all_pods_versions_6_f_0.txt, save ETag: W/"61bc05f5-34a"
  CDN: trunk Relative path downloaded: all_pods_versions_c_7_9.txt, save ETag: W/"61bc05f5-50d"
  CDN: trunk Relative path downloaded: all_pods_versions_1_9_2.txt, save ETag: W/"61bc05f5-1bb"
  CDN: trunk Relative path downloaded: CocoaPods-version.yml, save ETag: "61bc07cd-38"

备注：LibreSSL SSL_connect: SSL_ERROR_SYSCALL in connection to github.com:443，出现这个错误，一般是网络不好导致 git 连接失败，一般情况下，多更新几次就好了，需要一点点耐心。

5.OK，这次没有报错信息了，去xcode里面看看；
在AndroidStudio选择ios目录，点击右键，选择Xcode打开，在Xcode下确认以下几项：
1）.签名确定没有错误，这个非常重要！

   target -》signing & capabilities
   如果有错，去project -》info -》 configuration 把错误的版本删除再添加，可解决签名错误问题；必须先删除再添加，直接修改可能不起作用。

备注：对于ios端开发来说，签名是否正确非常重要，多个版本的签名，如果有一个版本的签名错了，可能导致一些不可预知的错误。
举个我同事的例子吧。
同一个项目，添加一个插件，我这边是成功的，他那边各种错误，初始化都不能成功，怎么样都解决不了。经过xcode配置对比发现，他的release版本的签名是报错的，把签名重新设置后，插件也可以正常使用了。

2）.确定没有包含不必要的配置

  target ->build phases->link binary with Libraries下查看，有没有不使用的framework，如果有就去掉；

6. 项目被更新后，再次执行：pod install --clean-install
报错信息如下所示：

Analyzing dependencies
[!] Unable to find a specification for `AlicloudPush (~> 1.9.9)` depended upon by `rammus`
You have either:
 * out-of-date source repos which you can update with `pod repo update` or with `pod install --repo-update`.
 * mistyped the name or version.
 * not added the source repo that hosts the Podspec to your Podfile.
[!] Automatically assigning platform `iOS` with version `12.0` on target `Runner` because no platform was specified. Please specify a platform for this target in your Podfile. See `[https://guides.cocoapods.org/syntax/podfile.html#platform](https://guides.cocoapods.org/syntax/podfile.html#platform)`.
ioskaifa110@ioskaifadeiMac ios % pod install --repo-update
Updating local specs repositories
Analyzing dependencies
[!] Unable to find a specification for `AlicloudPush (~> 1.9.9)` depended upon by `rammus`
You have either:
 * mistyped the name or version.
 * not added the source repo that hosts the Podspec to your Podfile.
[!] Automatically assigning platform `iOS` with version `12.0` on target `Runner` because no platform was specified. Please specify a platform for this target in your Podfile. See `[https://guides.cocoapods.org/syntax/podfile.html#platform](https://guides.cocoapods.org/syntax/podfile.html#platform)`.

7.根据6的提示，去修改Podfile文件,在头部添加：

source 'https://github.com/CocoaPods/Specs.git'
source 'https://github.com/aliyun/aliyun-specs.git'

备注：这项目使用了阿里云的移动推送，在Podfile配置中，需要加入这两个资源。

8.继续执行 pod install --clean-install

BMKLocationKit.release.xcconfig:1:1: unable to open file (in target "BMKLocationKit" in project "Pods")

上面的命令各自执行来了一遍，错误解决。

9.启动报错

↳
    ** BUILD FAILED **

Xcode's output:
↳
    error: the following command failed with exit code 0 but produced no further output
    CompileC /Users/ioskaifa110/....../ios/build/Pods.build/Debug-iphoneos/flutter_local_notifications.build/Objects-normal/arm64/FlutterLocalNotificationsPlugin.o /Users/ioskaifa110/Downloads/flutter/.pub-cache/hosted/pub.flutter-io.cn/flutter_local_notifications-8.1.1+1/ios/Classes/FlutterLocalNotificationsPlugin.m normal arm64 objective-c com.apple.compilers.llvm.clang.1_0.compiler (in target 'flutter_local_notifications' from project 'Pods')
    /Users/ioskaifa110/Downloads/flutter/.pub-cache/hosted/pub.flutter-io.cn/webview_flutter-2.0.13/ios/Classes/FlutterWebView.m:395:23: warning: 'requiresUserActionForMediaPlayback' is deprecated: first deprecated in iOS 10.0 [-Wdeprecated-declarations]
            configuration.requiresUserActionForMediaPlayback = true;

10.执行5.2，项目中有使用地图，是否缺少地图插件；

排除结果，少了一个系统库文件；

11.报错：Build input file cannot be found: '/Users/ioskaifa110/.../ios/plugins/mobpush/MobpushPlugin.m'

无用的插件没删除干净，到指定目录下删除；

12.报错：/Users/ioskaifa110/rsdun_flutter_app/ios/build/Pods.build/Release-iphoneos/SwiftyGif.build/module.modulemap:9:12: Header 'SwiftyGif-Swift.h' not found

解决办法：https://www.jianshu.com/p/00991deee746，不可以；
https://www.jianshu.com/p/0f6600a0cc67，不可以;

13.清除缓存：product -》clean
解决不了，那就试试清除缓存吧，在AndroidStudio开发中，经常使用这一招废弃缓存信息。

14.错误：Module 'agora_rtc_engine' not found

问题解决解决着，又回到了原点，相关命令在执行一遍。
flutter build iOS (flutter clean ,flutter pub get) 多次后，问题解决;

15.支付宝某个库文件找不到，使用xcode导入，问题解决。
在对接移动推送时，案例中曾写了一句话，请正确导入配置文件。刚开始我忽略了这句话，配置文件拷贝一下不就OK了吗？（当然，我也是ios开发小白，最近才踏进一只脚）
事实却不是这样的，必须使用Xcode的导入功能，xcode才能找到和识别配置文件，拷贝进去是找不到的，这或许和xcode的开发机制有关系吧！这可是我用大量时间换来的宝贵经验，特别适合小白。

最后总结
项目运行不起来，当然很着急，看到密密麻麻的报错信息，也很头疼。但是仔细研究了这些错误之后，发现解决这些错误并不费力，而且有规律可循，那就是根据英文的提示进行解决，有提示命令的运行提示命令即可，这些就可以解决百分之八十的错误了。