UIAlertController/ActionSheet crashes on iPad, how to pass sender? - ios

Question

I want to display an ActionSheet on both, iPhone and iPad devices. While my code works properly on iPhone's, it doesn't on iPad's. The reason for this is that I need to specify a location where to display the popover. As a result, I tried to used the code proposed in this answer. The problem that I currently have is, that I do not know how to pass the argument sender to the method.
For example, I have a UITableViewRowAction which when clicked should display the ActionSheet:
func tableView(tableView: UITableView, editActionsForRowAtIndexPath indexPath: NSIndexPath) -> [UITableViewRowAction]? {
let rowAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default, title: "Action", handler:{action, indexpath in
print("Action for element #\(indexPath.row).");
self.displayActionSheet()
});
return [rowAction];
}
Which argument is sender in my case? I am not able to pass rowAction to displayActionSheet(), because the variable is used within its own initial value. I also tried to pass self.displayDeleteLicencePlateActionSheet(self.items[indexPath.row]), but same result – I always end up in the else clause of the guard expression:
guard let button = sender as? UIView else {
print("sender empty")
return
}
I want to display also an ActionSheet when clicking on an UIBarButtonItem:
let myButton = UIBarButtonItem(title: "FooBar", style: .Plain, target: self, action: #selector(SecondViewController.displaySecondActionSheet(_:)))
But same result. How can this be done?

Answer 1

Please refer following code to fix your issue.
TARGET_OBJECT will be your sender where from you want to show an alert.
func showAlert() {
let alert = UIAlertController(title: "Title", message: "Message text", preferredStyle: .alert)
let actionOK = UIAlertAction(title: "OK", style: .default) { (alertAction) in
}
alert.addAction(actionOK)
if let popoverController = alert.popoverPresentationController {
popoverController.sourceView = self.TARGET_OBJECT // TARGET_OBJECT will be your sender to show an alert from.
popoverController.sourceRect = CGRect(x: self.TARGET_OBJECT.frame.size.width/2, y: self.TARGET_OBJECT.frame.size.height/2, width: 0, height: 0)
}
UIApplication.shared.keyWindow?.rootViewController?.present(alert, animated: true, completion: nil)
}
Please check attached image it will appear as you want.