iphone - How to use NSInvocation to call a class method? -


i've class method not declared in h file, implemented in m file. want call in class, since return value int, can't use selector directly, use nsinvocation.

below i'm doing:

sel selector = ***; nsmethodsignature *signature = [classa methodsignatureforselector:selector]; nsinvocation *invocation = [nsinvocation invocationwithmethodsignature:signature]; invocation.selector = selector; invocation.target = [classa class]; [invocation setargument:(void *)arg atindex:2]; [invocation invoke];

the invoke doesn't succeed, why?

when passing arguments, pass address, not value. try following:

[invocation setargument:&arg                 atindex:2];

see [nsinvocation setargument:atindex:] in class reference.


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