Question

the UIActionSheet crashes after it appears the second time through..

.H file

..UIActionSheetDelegate>{

 UIActionSheet *popupQuery;
}
@property (nonatomic, retain) UIActionSheet *popupQuery;

.M file

-(IBAction)showActionSheet:(id)sender {

if (popupQuery.visible) {
    NSLog(@"popupQuery isVisible");

    [popupQuery dismissWithClickedButtonIndex:-1 animated:YES];

    return;
}else{


popupQuery = [[UIActionSheet alloc] initWithTitle:@"Title" delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:@"Readibility" otherButtonTitles:@"Email URL", @"Print", nil];
popupQuery.actionSheetStyle = UIActionSheetStyleBlackOpaque;
//[popupQuery showInView:self.view];


[popupQuery showFromBarButtonItem:actionButton animated:YES];

[popupQuery release];
}
  }

Answer 1

When you release popupQuery after showing it from actionButton, you relinquish ownership on the object. If the object gets deallocated then popupQuery will point to a deallocated object which when you do popupQuery.visible might give you a crash. Since you have it as a property, you can do this –

self.popupQuery = [[[UIActionSheet alloc] initWithTitle:@"Title" delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:@"Readibility" otherButtonTitles:@"Email URL", @"Print", nil] autorelease];

Remove the release statement at the end. Now the object will be valid when you popupQuery.visible or self.poupQuery.visible In this case, you will have the ownership and you can safely access the object.