Open Radar

 
When in a large codebase that has a sidebar with folders for all organizational needs, sometimes I would like to reduce the noise, visual clutter, and distraction and focus on just a few classes when debugging.

OmniFocus for the Mac has a feature called "Focus," where you can select multiple projects, then click the "Focus" toolbar button to hide everything else in the sidebar. It allows for a clean, clutter-free workspace to help you focus on the task(s) at hand. (described here: https://support.omnigroup.com/documentation/en/omnifocus-2-for-mac-user-manual/focusing) 

In Xcode, I could see this working in a similar way. Click a few classes (selecting a *.m file would automatically include it's header file), click a Focus toolbar button and the sidebar would be reduced to just those classes. If I -click on a class in the body of one of these focused files and the class is not being focused on in the sidebar, the class would then be added to the sidebar of focused items.