Either wait X seconds or for a user input - ios

Question

I'm very new to swift so even this is a bit complicated to me at this point; sorry for sounding dumb if I do
Preface:
I have a main view controller(lets call it viewA) and a UIView which gets its functionality from a .xib file, let's call this viewB
This is all in the single main view controller page
The problem:
So i want my ViewController to execute a bunch of methods in sequence one of which is to call the result from a function in this viewB(its a subview so i cant use segues)
So in the function i want to return the result only when either--
A button to be pressed
30 seconds have passed
Whats the most efficient way to tackle this problem?
EDIT:
In a nutshell i want to make my main queue execution wait till there is an input from the player or 30 seconds have passed
Code structure:
ViewController:
class ViewController{
var viewB:CustomView
//methods
function to execute{
viewB.executeFunction()
}
}
CustomView:
class CustomView:UIView{
//functions of initializing buttons and text boxes
func executeFunction(){
//wait for a user input to complete then return from this function. i cant figure out how this works
}
}
Image of the UI idea

Answer 1

I think Option 1 is more suitable for your scenario. You can call the block when the button in your nib is pressed. Following is the code how you can use block in swift:
// Code for your UIViewController
func presentPopup() {
let popup = NibClassName.instantiateViewFromNib()
popup.btnPressBlock = { [unowned self] (success) -> () in
// Code after button of UIView pressed
}
popup.frame = CGRect(x: 100, y: 100, width: 300, height: 300)
self.view.addSubview(popup)
}
// Code of your UIView class file
var btnPressBlock: ((Bool) -> ())?
class func instantiateViewFromNib() -> NibClassName {
let obj = Bundle.main.loadNibNamed("NibName", owner: nil, options: nil)![0] as! NibClassName
return obj
}
#IBAction func btnPressed(sender: UIButton) {
btnPressBlock!(true)
removeFromSuperview()
}