In class A I have this:
static NSString * const kMyConstant = @"my constant string";
How can I reference this from class B?
You should extern your string in the header, and then define the string in the implementation.
//ClassA.h extern NSString * const kMyConstant; //ClassA.m NSString * const kMyConstant = @"my constant string"; //ClassB.h/m #import "ClassA.h" ... NSLog(@"String Constant: %@", kMyConstant);
You need to remove the static
-- that specifies that kMyConstant
is only visible in files linked with this one.
Then, declare (as opposed to defining) the string in Class A's header:
extern NSString * const kMyConstant;
and import that header wherever you want to use this string. The extern
declaration says that there exists an NSString * const
by the name kMyConstant
whose storage is created in some other place.
If the static definition is already in the header, you need to move it elsewhere (usually the implementation file). Things can only be defined once, and if you try to import a file which defines a variable, you'll get a linker error.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With