Information Technology Reference
In-Depth Information
Understanding the Levels view
The Levels view has four columns when viewing target settings, and three columns when viewing project set-
tings. It's not immediately obvious how this view works, but the design becomes clearer after you understand
how it's organized.
There are two key points. The first is that Xcode build settings cascade through multiple levels of defaults. Each
level overrides the previous level. When Xcode creates a build, it uses this table to find the settings with the
highest priority and applies those to the build.
The order of priority flows from right to left. These columns are present:
OS default:
These are the standard default switches that apply when the other rows are empty.
Project settings:
This list shows the Project build settings. It's identical to the list you can view by select-
ing the PROJECT icon and All/Combined buttons under the Build Settings tab. These settings override the
OS defaults. If a project has multiple targets, the settings apply to all of them.
Target settings:
This list shows the Target build settings for the current selected target. It's identical to
the list you can view by selecting the All/Combined buttons. These settings override the project settings and
the OS defaults. If your project has multiple targets, the settings in this column apply to the currently selec-
ted target. Other targets can have different settings.
Resolved:
These are the final calculated settings applied to the build. Because they're calculated from the
other columns, you can't edit them.
