Question

I just updated my app so that it’s a universal app. In doing so I added support for UIPopoverController in a certain place. Now the app seems to be crashing on 3.1.3 iPhone/iTouch devices:

OS Version:      iPhone OS 3.1.3 (7E18)
Report Version:  104

Exception Type:  EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x00000001, 0xe7ffdefe
Crashed Thread:  0

Dyld Error Message:
  Symbol not found: _OBJC_CLASS_$_UIPopoverController

What I don’t get is that I’m only trying to call UIPopoverController if the hardware is an iPad:

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
    UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:btc];
    CGSize popoverSize = { 300.0, 500.0 };
    popover.delegate = self;
    popover.popoverContentSize = popoverSize;
    self.bmPopover = popover;
    [popover release];

    [self.bmPopover presentPopoverFromBarButtonItem:self.bmBarButtonItem permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
} else {
    [self presentModalViewController:nav animated:YES];
}

I do have an iVar and a property of type UIPopoverController declared but I wouldn’t have expected this to cause an issue at runtime if I didn’t actually try to call methods in the class.

What am I supposed to do to make sure that the system doesn’t try to link with UIPopoverController at runtime when this isn’t supported?

Answer 1

For Universal app you should not only check if this is ipad or does this class exists but you should link UIKit as Weak reference a not default ( strong ), to do this:

1. get to target info
2. select general
3. in linked libraries change UIKit required to UIKit weak

Have fun making universal apps :]