Question

I am writing a function in objective C.
That is what I got:

int rndValue = (((int)arc4random()/0x100000000)*width);
timer1 = [NSTimer scheduledTimerWithTimeInterval:.01 
                                          target:self 
                           [self performSelector:@selector(doItAgain1:)  
                                      withObject:rndValue] 
                                        userInfo:nil
                                         repeats:YES];

The selector invokes this method and passes parameter:

-(void)doItAgain1:(int)xValuex{
}

At this stage the top code produces syntax error. Syntax error: 'Expected ] before performSelector' What is the prob?
Best regards

Answer 1

This would be more correct:

[NSTimer scheduledTimerWithTimeInterval:.01 target:self 
                 selector:@selector(doItAgain1:)
                 userInfo:[NSNumber numberWithInt:rndValue] repeats:YES];

Also notice that the syntax for the selector you call in this way must be:

- (void)doItAgain1:(NSTimer*)timer {

   int rndValue = [timer.userInfo intValue];
   ...
}

It is not possible to specify an int argument to such a timer selector, thus the trick to convert it into a NSNumber object.