How to create UIActionSheet actions? - ios

Question

I know I have to set the delegate (I did so like this: class ShiftOverview: UITableViewController, UIActionSheetDelegate {...) but I'm still getting no response when I tap the buttons.
It doesn't look like you can set the delegate within the function with UIAlertController either...
#IBAction func takeShift(sender: AnyObject) {
let myActionSheet = UIAlertController (title: "Confirm", message: "Test message", preferredStyle: UIAlertControllerStyle.ActionSheet)
let actionOne = UIAlertAction (title: "Take Shift", style: .Default, handler: nil)
let actionTwo = UIAlertAction (title: "View ESA", style: .Default, handler: nil)
let actionCancel = UIAlertAction (title: "Cancel", style: .Cancel, handler: nil)
myActionSheet.addAction(actionOne)
myActionSheet.addAction(actionTwo)
myActionSheet.addAction(actionCancel)
self.presentViewController(myActionSheet, animated: true, completion: nil)
}
func actionSheet (myActionSheet: UIActionSheet, clickedButtonAtIndex buttonIndex: Int)
{
switch buttonIndex {
case 0:
println ("test0")
break
case 1:
println ("test1")
break
case 2:
println ("test2")
break
default:
println("nope")
}
}

Answer 1

Prior to iOS 8, UIAlertViews and UIActionSheets were separate controls. In iOS 8 however, a new class, UIAlertController, combines both these controls into a single, easy to use class.
Rather than using the delegation pattern like these controls used to, you now pass a closure to be called. The places where you have handler equal to nil is where you put your code.
This is likely added because Swift treats closures as first-class citizens, while Objective C did not as much (with blocks).
It should be:
#IBAction func takeShift(sender: AnyObject) {
let myActionSheet = UIAlertController (title: "Confirm", message: "Test message", preferredStyle: UIAlertControllerStyle.ActionSheet)
let actionOne = UIAlertAction (title: "Take Shift", style: .Default, handler: { (action) in
println("test0")
})
let actionTwo = UIAlertAction (title: "View ESA", style: .Default, handler: { (action) in
println("test1")
})
let actionCancel = UIAlertAction (title: "Cancel", style: .Cancel, handler: { (action) in
println("test2")
})
myActionSheet.addAction(actionOne)
myActionSheet.addAction(actionTwo)
myActionSheet.addAction(actionCancel)
self.presentViewController(myActionSheet, animated: true, completion: nil)
}
Read more about this in NSHipster's article on UIAlertControllers or in its documentation.

Answer 2

Instead of passing nil to your handler, you can write the action you want to perform. You don't need the delegate method anymore.
let actionOne = UIAlertAction (title: "Take Shift", style: .Default){ (action) -> Void in
println ("Take Shift")
};
let actionTwo = UIAlertAction (title: "View ESA", style: .Default){ (action) -> Void in
println ("View ESA")
};
let actionCancel = UIAlertAction (title: "Cancel", style: .Cancel){ (action) -> Void in
println ("Cancel")
};

Answer 3

You may like to see this also:
func AlertViewWithActionsheet () {
let alert = UIAlertController(title: "Alert with actionsheet", message: "Alert with actionsheet", preferredStyle: UIAlertControllerStyle.ActionSheet);
let dismissHandler = {
(action: UIAlertAction!) in
// This is an action event - called when you press OK button.
self.dismissViewControllerAnimated(true, completion: { () -> Void in
})
}
// add action
alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: dismissHandler))
presentViewController(alert, animated: true) { () -> Void in
}
}