Try this:
Swift 4
myButton.addTarget(self,
action: #selector(myAction),
for: .touchUpInside)
Objective-C
[myButton addTarget:self
action:@selector(myAction)
forControlEvents:UIControlEventTouchUpInside];
You can find a rich source of information in Apple's Documentation. Have a look at the UIButton's documentation, it will reveal that UIButton is a descendant of UIControl, which implements the method to add targets.
--
You'll need to pay attention to whether add colon or not after myAction
in
action:@selector(myAction)
Here's the reference.