原因可能是“Podfile冲突”。(前。如果:合并后的源代码.v.v.)

这是“简单的方法”，“重新安装Pod文件”。

要完全清洁(删除所有点链接)，并创建升级到新的(卸载和再次安装太)，

写如下命令:

flutter clean

rm -Rf ios/Pods
rm -Rf ios/.symlinks
rm -Rf ios/Flutter/Flutter.framework
rm -Rf ios/Flutter/Flutter.podspec

然后按照这个命令复制Podfile

rm ios/Podfile

最后，运行项目即可：

flutter run

原文：

The reason might be Podfile conflict. (ex. in case : after merge source code .v.v.)

It is easy way, re-install Pod file.

To completely clean (Removing all points to links) and create upgraded to the new (uninstall and installing again too),

Write following command :

flutter clean

rm -Rf ios/Pods
rm -Rf ios/.symlinks
rm -Rf ios/Flutter/Flutter.framework
rm -Rf ios/Flutter/Flutter.podspec

Then for reproduce Podfile follow this command

rm ios/Podfile

Finally your project is ready to good to go

flutter run