Question

I have tried and got “SIGBRT” exception.
In Global.m, I have methodBGlobal().

In ClassA, I included Global.h in order to use methodGlobal().
ClassA.methodA() has methodGlobal() in it.

Then I have button in Global.m. Since I do not know how to call methodGlobal() properly in Global.m. SO I call the methodGlobal() through ClassA instance.

[mybutton addTarget:ClassA instance action:@selector(methodA:) ...];

It does not work. I got “SIGBRT” exception and I do not know that methodGlobal() in ClassA.methodA() was called or not? I want methodGlobal to work.

Answer 1

Two things you need to consider here.

1. If the method is a class method, then the target should be [ClassA class].
2. If the method signature doesn’t include any arguments , for ex., -(void) methodA; then, there should be not colon(“:”) included in the @selector. So, the selector should be just @selector(methodA).

Finally the addTarget: method should look like,

[mybutton addTarget:[ClassA class] action:@selector(methodA) ...];

References:

1. Target-Action from Cocoa Application Competencies for iOS.
2. The Target-Action Mechanism from Cocoa Fundamentals Guide.