uncaught exception 'NSGenericException: application has presented a UIAlertController of style UIAlertControllerStyleActionSheet - ios

Question

I am working on an app which i run on iPhone works well but when i am trying to run on iPad it crashes
Here is my code:
- (void)parseCountryStates:(NSDictionary *)json
{
countryPickerView.hidden = TRUE;
NSDictionary *listing = [json objectForKey:#"country"];
countryArray = [listing allValues];
countryIDArray = [listing allKeys];
[countryPickerView reloadAllComponents];
alertController = [UIAlertController
alertControllerWithTitle:#"Select Service Type"
message:nil
preferredStyle:UIAlertControllerStyleActionSheet];
int count = (int)[countryPickerView numberOfRowsInComponent:0];
for (int i = 0; i < count; i++)
{
UIAlertAction* button = [UIAlertAction
actionWithTitle:[[countryPickerView delegate] pickerView:countryPickerView titleForRow:i forComponent:0]
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
countryField.text = [action title];
countryStr = countryField.text;
if ([countryArray containsObject:countryStr]) {
countryidStr = [countryIDArray objectAtIndex:[countryArray indexOfObject:countryStr]];
NSLog(#"CountryidStr %#",countryidStr);
[self getState];
}
}];
[alertController addAction:button];
}
UIAlertAction* cancel = [UIAlertAction
actionWithTitle:#"Cancel"
style:UIAlertActionStyleCancel
handler:^(UIAlertAction * action)
{
// UIAlertController will automatically dismiss the view
}];
[alertController addAction:cancel];
[self presentViewController:alertController animated:true completion:nil];
}
I am sharing the crash log of it
*** Terminating app due to uncaught exception 'NSGenericException', reason: 'Your application has presented a UIAlertController () of
style UIAlertControllerStyleActionSheet. The modalPresentationStyle of
a UIAlertController with this style is UIModalPresentationPopover. You
must provide location information for this popover through the alert
controller's popoverPresentationController. You must provide either a
sourceView and sourceRect or a barButtonItem. If this information is
not known when you present the alert controller, you may provide it in
the UIPopoverPresentationControllerDelegate method
-prepareForPopoverPresentation.

Answer 1

Add source view and source rect to your alertController.
[[alertController popoverPresentationController] setSourceView:self.view];
[[alertController popoverPresentationController] setSourceRect:CGRectMake(0,0,1,1)];
[[alertController popoverPresentationController] setPermittedArrowDirections:UIPopoverArrowDirectionUp];
[self presentViewController:alertController animated:true completion:nil];

Answer 2

actully on ipad alertcontrollers are not allowed instead you can use pop overs to diaplay kind of alert
Programtically
UIViewController *newViewCont = [[UIViewController alloc] init];
newViewCont.view = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 180, 180)];
newViewCont.modalPresentationStyle = UIModalPresentationPopover;
[self presentViewController:newViewCont animated:YES completion:nil];
UIPopoverPresentationController *pop = [newViewCont popoverPresentationController];
pop.permittedArrowDirections = UIPopoverArrowDirectionAny;
[pop setSourceView:myButton];
[pop setSourceRect:myButton.bounds];
Using storyboards
// grab the view controller we want to show
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *controller = [storyboard instantiateViewControllerWithIdentifier:#"Pop"];
// present the controller
// on iPad, this will be a Popover
// on iPhone, this will be an action sheet
controller.modalPresentationStyle = UIModalPresentationPopover;
[self presentViewController:controller animated:YES completion:nil];
// configure the Popover presentation controller
UIPopoverPresentationController *popController = [controller popoverPresentationController];
popController.permittedArrowDirections = UIPopoverArrowDirectionUp;
popController.delegate = self;
// in case we don't have a bar button as reference
popController.sourceView = self.view;
popController.sourceRect = CGRectMake(30, 50, 10, 10);
dismiss popover
[self dismissViewControllerAnimated:YES completion:nil];
There’s a new protocol called the UIPopoverPresentationControllerDelegate that is called upon dismissal and position change due to rotation or interface changes. We can even prevent a Popover from being dismissed if we wish. Here are the three methods we can implement:
- (void)popoverPresentationControllerDidDismissPopover:(UIPopoverPresentationController *)popoverPresentationController {
// called when a Popover is dismissed
}
- (BOOL)popoverPresentationControllerShouldDismissPopover:(UIPopoverPresentationController *)popoverPresentationController {
// return YES if the Popover should be dismissed
// return NO if the Popover should not be dismissed
return YES;
}
- (void)popoverPresentationController:(UIPopoverPresentationController *)popoverPresentationController willRepositionPopoverToRect:(inout CGRect *)rect inView:(inout UIView *__autoreleasing _Nonnull *)view {
// called when the Popover changes position
}
Don’t forget to conform to the protocol, and set the delegate to your reacting class.

Answer 3

UIPopovers are not allowed on iPads, but there is a way you can do this as other answers have indicated. Here is a Swift 5.x version.
let ac = UIAlertController(title: "Some title goes here", message: nil, preferredStyle: .actionSheet)
ac.addAction(UIAlertAction(title: "Some button name", style: .default) {
[unowned self] _ in
// stuff to do goes here
self.doSomething()
})
// iPad specific code
ac.popoverPresentationController?.sourceView = self.view
let xOrigin = nil // Replace this with one of the lines at the end
let popoverRect = CGRect(x: xOrigin, y: 0, width: 1, height: 1)
ac.popoverPresentationController?.sourceRect = popoverRect
ac.popoverPresentationController?.permittedArrowDirections = .up
present(ac, animated: true)
Replacing the the let xOrigin = nil line with one of the ones below will control where the popover appears below the navigation bar. You can also change x and y to the proper value in the bounds or frame of a different element if you have control that is below the nav bar on an iPad.
Top Left
let xOrigin = 0
Top Middle
let xOrigin = self.view.bounds.width / 2
Top Right
let xOrigin = self.view.bounds.width
Hope this helps.