问题
What are these?

specifically the A/M/? marks near some of the files? what each letter means?
It's a project which I imported from previous xcode version (and iOS 4). The projects compiles alright though. My new storyboard/iOS 5 projects do not show these marks. What do they represent and how can I set/reset these?
thanks
回答1:
These are source control management (SCM) status boxes, from git or subversion as Ell has mentioned.
The specific statuses:
A - added to the local repository (new file that doesn't exist in the remote repository yet)
M - Modified (existing file that has been changed)
? - File that exists on the file system but hasn't been added to the repository, locally or remotely. You can add it by right clicking on the file, source control, add.
回答2:
There symbols represent SCM status, either from git or subversion. If you're not using SCM, you can ignore them.
来源:https://stackoverflow.com/questions/8978161/xcode-file-mark-boxes-in-project-navigator