when to use respondsToSelector in objective-c

Question

- (void)someMethod
{
    if ( [delegate respondsToSelector:@selector(operationShouldProceed)] )
    {
        if ( [delegate operationShouldProceed] )
        {
             


        

Answer 1

Just to add to what @kubi said, another time I use it is when a method was added to a pre-existing class in a newer version of the frameworks, but I still need to be backwards-compatible. For example:

if ([myObject respondsToSelector:@selector(doAwesomeNewThing)]) {
  [myObject doAwesomeNewThing];
} else {
  [self doOldWorkaroundHackWithObject:myObject];
}