git 子模块更改默认目录相关错误

1.首先:给项目添加子模块 git submodule add 出现 already exists and is not a valid git repo

git submodule add  http://XXXXXXXXXXXXXXX.git    'XXXXXX/XXXXXX/XXXXXX/' (目录名称)    already exists and is not a valid git repo

说明目录已经存在，删除该目录，然后重试此命令

2.其次:继续

 git submodule add  http://XXXXXXXXXXXXXXX.git    'XXXXXX/XXXXXX/XXXXXX/' 

The following path is ignored by one of your .gitignore files:

XXXXXX/XXXXXX/XXXXXX/

Use -f if you really want to add it.

3. git submodule add -f http://XXXXXXXXXXXXXXX.git 'XXXXXX/XXXXXX/XXXXXX/'

(注意选定目录前面没有/ ,否则会出错)

如果出现：fatal: not a git repository cd当相关目录直接git init 继续执行1，2，3的操作