Objective-c – How to define a preprocessor symbol in Xcode


Is it possible to set a symbol for conditional compilation by setting up properties in an Xcode project?

My aim is to to create a symbol that is available to all files, without having to use import/include, so that a set of common classes can have a special behavior in some projects. Like the following, but with my own symbols.


Best Solution

Go to your Target or Project settings, click the Gear icon at the bottom left, and select "Add User-Defined Setting". The new setting name should be GCC_PREPROCESSOR_DEFINITIONS, and you can type your definitions in the right-hand field.

Per Steph's comments, the full syntax is:

constant_1=VALUE constant_2=VALUE

Note that you don't need the '='s if you just want to #define a symbol, rather than giving it a value (for #ifdef statements)