Question

How does one implement a raw callback in objective C?

I just want to notify a ViewController when one of my UITableViewCell objects(custom cell) detects touch.

I need to notify my RootViewController so that it can create an object of another ViewController and push it on the navigation stack.

Answer 1

You can use a custom init method like below for secondVC and store the _sender in global or class variable. like

id sender;

- (id)initWithSender:(id)_sender
{
    self = [super init];
    if (self) {
        sender=_sender;
    }
    return self;
}

from RootVC initialize secondvc as follows and define a method named -(void) touchDetected; in rootvc.

    secondvc=[[SecondVC alloc] initWithSender:self];
    [[self navigationController] pushViewController: secondvc animated:YES];    

when the touch is detected in secondvc call, this will notify your rootvc that the touch is detected in secondvc.

[sender touchDetected];