On 9/14/05, Keith Alperin <email@hidden> wrote:
Greetings Cocoa-Devs!
I'm trying to implement a callback using an NSInvocation. However,
when i call invoke, i get: "<NSInvalidArgumentException> *** -
[MyTestApp methodSignatureForSelector:]: null selector".
Here is some test code that I am using:
- (void)awakeFromNib {
SEL *handlerSelector = @selector(someMethod: otherArg:);
NSMethodSignature *signature = [self methodSignatureForSelector:
handlerSelector];
NSInvocation *handler = [NSInvocation
invocationWithMethodSignature: signature];
[handler setTarget:self];
[handler retain];
You never call setSelector: on the invocation, so it has a method
signature but no idea what method to call. Signatures just contain
type information. Also, handlerSelector should be of type SEL, not SEL
*.
