you should configure UIAlertController to be presented on a specific point on iPAD.

Example for navigation bar:

    // 1
    let optionMenu = UIAlertController(title: nil, message: "Choose an option", preferredStyle: .actionSheet)

    // 2
    let deleteAction = UIAlertAction(title: "Option 1", style
 
: .default, handler: {
        (alert: UIAlertAction!) -> Void in
        print("option 1 pressed")
    })
    let saveAction = UIAlertAction(title: "Option 2", style: .default, handler: {
        (alert: UIAlertAction!) -> Void in
        print("option 2 pressed")
    })

    // 3
    let
 
 cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: {
        (alert: UIAlertAction!) -> Void in
        print("Cancelled")
    })

    // 4
    optionMenu.addAction(deleteAction)
    optionMenu.addAction(saveAction)
    optionMenu.addAction(cancelAction)

    // 5
  if UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad {
 optionMenu.popoverPresentationController?.barButtonItem = self.navigationItem.rightBarButtonItem
 optionMenu.popoverPresentationController?.permittedArrowDirections = .init(rawValue: 0)
 optionMenu.popoverPresentationController?.sourceView = self.view
 optionMenu.popoverPresentationController?.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
 }
    
 
self.present(optionMenu, animated: true) { 
        print("option menu presented")
    }

sample 2:

let alert = UIAlertController(title: "Alert Title", message: "Alert Message", style = .Alert)
for i in ["hearts", "spades", "diamonds", "hearts"] {
    alert.addAction(UIAlertAction(title: i, style: .Default, handler: doSomething)
}
self.presentViewController(alert, animated: true, completion: nil)

And handle the action here:

func doSomething(action: UIAlertAction) {
    //Use action.title
}

On an iPad, an action sheet is a popover. Therefore you must give its UIPopoverPresentationController a sourceView and sourceRect, or barButtonItem, so that it has something to attach its arrow to.