my popovercontroller terminating - ios

Question

I am creating image based application.Now I have allocated and synthesized pickerviewcontroller in my viewcontroller.m class.
as UIImagePickerController *picker. Here I have Give it to the (IBAction).
-(IBAction)selectphoto:(id)sender
{
picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
[self presentViewController:picker animated:YES completion:NULL];
}
Then i have set it`s delegate methods.
Now, In my another class named as imagedisplay.m,I have created one Button, at which i want to create popupviewcontroller with my imagepickercontroller images(which is in my viewcontroller class),
Below is my code,
-(IBAction)gallery:(id)sender
{
NSLog(#"pop over done.");
ViewController *vcntrlr = [[ViewController alloc] init];
UIPopoverController *popover_=[[UIPopoverController alloc] initWithContentViewController:vcntrlr.picker];
[popover_ setDelegate:self];
[popover_ presentPopoverFromRect:CGRectMake(100, 280,100,100) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];
}
I expecting for Displaying popover controller.BUt when i tryng to press Button((IBAction)gallery) my application is terminated and seems below error.
"terminating with uncaught exception of type NSException".
Help me .

Answer 1

My first guess would be that you are not holding any strong reference to the popovercontroller, so it will be released outside the scope of the -(IBAction)gallery:(id)sender method. To ensure the popover controller is kept alive after the method has finished, you should keep a strong reference to it.
To do so you can add a property to your class:
#property (strong, nonatomic) UIPopoverController* popoverController;
And change your code into:
self.popoverController = [[UIPopoverController alloc] initWithContentViewController:vcntrlr.picker];
[self.popoverController setDelegate:self];
[self.popoverController presentPopoverFromRect:CGRectMake(100, 280,100,100) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];