A lot development is spent just looking for things: determining what code calls a certain method or uses a particular constant, or changing the name of a class or method name everywhere in your project. Xcode has tools to help you quickly find what you're looking for in a single file, the files in a project, and beyond.
The single file search tools are found in the Find menu. Find
Figure 7-1. Figure 7-1
The Single File Find window contains all search and replace commands and options in a single window. The subject of the search is the file of the last editor pane that was active before you opened or switched to the Single File Find window. If you leave the window open, switch to a different editor pane, and then switch back to the Single File Find window, a search or replace occurs in the more recent file, not the one that was active when the window was originally opened. If you're ever in doubt, close the window, activate the editor pane of the file you want to search, and reopen the Find window using Command+F.
Enter the pattern you want to search for in the Find field. If you are going to replace multiple occurrences of what you find, enter the replacement text in the Replace field. Press the Tab key to move the selection from one to the other. ...