How to I pass @selector as a parameter?

Solution 1:

The problem here isn't passing a selector to a method, per se, but passing a selector where an object is expected. To pass a non-object value as an object, you can use NSValue. In this case, you'll need to create a method that accepts an NSValue and retrieves the appropriate selector. Here's an example implementation:

@implementation Thing
- (void)method:(SEL)selector {
    // Do something
}

- (void)methodWithSelectorValue:(NSValue *)value {
    SEL selector;

    // Guard against buffer overflow
    if (strcmp([value objCType], @encode(SEL)) == 0) {
        [value getValue:&selector];
        [self method:selector];
    }
}

- (void)otherMethodShownInYourExample {
    SEL selector = @selector(something);
    NSValue *selectorAsValue = [NSValue valueWithBytes:&selector objCType:@encode(SEL)];
    [NSThread detachNewThreadSelector:@selector(methodWithSelectorValue:) toTarget:self withObject:selectorAsValue];
}
@end

Solution 2:

You can convert between selectors and string objects using the NSStringFromSelector() and NSSelectorFromString() functions. So you can just pass string objects instead.

Alternately, if you don't want to change your methods, you can create an NSInvocation to create an invocation for your method call (since it can set up invocations with non-object arguments), and then to call it do [NSThread detachNewThreadSelector:@selector(invoke) toTarget:myInvocation withObject:nil];