Share Sheet Crashing on iPad - ios

Question

I'm creating a share sheet where someone can share the text from a text field. I've got it working on the iPhone, but the app crashes on the iPad. I know that it has to be in a popover form and have had this issue back in the day of Objective-C, but I can't seem to figure it out on Swift. This is my code that I've got going for the share sheet:
#IBAction func myShareButton(sender: AnyObject) {
// Hide the keyboard
textView.resignFirstResponder()
// Check and see if the text field is empty
if (textView.text == "") {
// The text field is empty so display an Alert
displayAlert("Warning", message: "You haven't written anything yet!")
} else {
// We have contents so display the share sheet
displayShareSheet(textView.text!)
}
}
// Show Warning
func displayAlert(title: String, message: String) {
let alertController = UIAlertController(title: title, message: message, preferredStyle: .Alert)
alertController.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
presentViewController(alertController, animated: true, completion: nil)
return
}
// Display Share Sheet
func displayShareSheet(shareContent:String) {
let activityViewController = UIActivityViewController(activityItems: [shareContent as NSString], applicationActivities: nil)
presentViewController(activityViewController, animated: true, completion: {})
}

Answer 1

I implemented share sheets today as well and had the exact same issue. You need to add this before presenting.
if let popoverPresentationController = activityController.popoverPresentationController {
popoverPresentationController.sourceView = self.view
popoverPresentationController.sourceRect = CGRect(x: CGRectGetMidX(view.bounds), y: CGRectGetMidY(view.bounds), width: 0, height: 0)
popoverPresentationController.permittedArrowDirections = UIPopoverArrowDirection.init(rawValue: 0) //Removes arrow as I dont want it
}
Line 1 sets the source view.
Line 2 I use to Center the popover right in the middle (I use it in SpriteKit and the popover is not attached to anything)
Line 3 I use to remove the arrow as I don't want it.
Hope this helps

Answer 2

for Swift 3/4
Depends on #crashoverride777 Answer
if let popoverPresentationController = activityVC.popoverPresentationController {
popoverPresentationController.sourceView = self.view
popoverPresentationController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
popoverPresentationController.permittedArrowDirections = UIPopoverArrowDirection.init(rawValue: 0) //Removes arrow as I dont want it
}