I am running a MacPro7,1 with Big Sur 11.6 and Xcode 13.0. When I open the main nib file for my application, the editor is completely blank -- nothing shows up. The app builds and runs as expected, so it is not like the nib has vanished.
The nib has been visible recently, but I am not aware of anything unusual that I might have done to it to cause damage.
The behavior repeats after a project clean, and also after closing Xcode and reopening it.
Does anyone have any ideas of what might be going on, and how to fix the problem?
The storyboard is not scrolled off view, and what is very strange is, that when I pull down the Editor menu with the nib view selected, it does not have a Minimap entry -- it is not that the entry is grayed out, there is no such entry.
I have not tried to create a new project, but the problem seems to occur with several different existing nib files.
I have not seen this problem in Xcodes previous to Xcode 13.
I find no relevant errors in the issues navigator. In particular, I ran a full analyze and no messages came up concerning the nib file. And as I said before, the builds complete with no errors and the product runs as expected.
I have MORE INFORMATION:
When I do the following:
1) Close Xcode.
2) Locate the nib file in question in the finder.
3) Control-click the nib file in the finder, and select "Open with Xcode" ...
Then Xcode opens the nib file in a different kind of window than the one that opens when I open a project. This "different" window shows just the nib file. This window perhaps resembles Interface Builder windows from the days when the Interface Builder was a separate application. The window shows the nib file and allows me to edit it, and changes I make there show up when I (subsequently) open the project, then build and run it. But I still cannot view the nib file in the project viewer, even after I have edited it in the different window, and closed and reopened Xcode.
I have noticed one odd thing. In the "different" window, the editor in that window identifies the nib by name and has a "Type" pull-down menu, which shows "Default -- Interface Builder Cocoa NIB". But when I look at the nib file in the project-viewer window, the editor there does not have a "Type" menu at all.
I conjecture that Xcode's project-viewing system has somehow gotten the wrong idea of what the nib file's type is (since Xcode's build system evidently can deal with the file, and the "different" window can also deal with it). But I may be wrong, and have no idea how to debug further.
