First, if you are unfamiliar with svn, its best to brush up on that before starting this. There are many many source within google reach so I won't dwell on that here. Now, on to Xcode...
Before you can reference a repository you need to se it up. Here is how:
In Xcode select Preferences from the Xcode menu and choose the SCM tab from that window. That area will list the repositories you have set up, presumably none at this point.
Add a repository by clicking the plus sign on the bottom left under the repository list. Give it a name (your choice) and set the SCM System to be subversion.
Clicking OK will bring up an empty template for the server settings. You can fill this out by entering the entire URL with username, or ignoring the URM field and filling in the other details.
Note : assuming you do this field by field, I strongly recommend putting in the scheme (i.e. https) last to prevent Xcode from attempting to log in before the info is complete. It will basically try and authenticate on the fly, and on several occasions this has caused account lock-outs when it tried to authenticate multiple times with incomplete passwords.
If all went well, there will be a little green light under password with the word Authenticated beside it.
At this point the repository is set up. You should be able to browse it and work with it by selecting Repositories from the SCM menu in Xcode. From there you can checkout the projects you like.
Once you have a project directory that you have checked out from subversion you can set it up to show the status and do check ins etc from Xcode. This is very simple - it is just not very obvious.
- Open the Xcode project from the checked out directory.
- Right click on the project file inside Xcode at the very top of the Groups & Files list and select Get Info from the context menu.
- Select the General tab at the top of the window that comes up and click
the button marked "Configure Roots & SCM".
- That will show a list of repositories - if the list is empty click the plus sign to create one.
- The root should be your project area. If you don't do anything you should see "" in the field - this works for most setups.
- The repository field will have a drop down box with any configured repositories Xcode knows about. Select the one that you set up for our subversion area in the previous steps above.