啊，没关系。查看Apple的示例应用程序TopPaid

Ahhhh nevermind. Check out Apple's example app "TopPaid"

这有点hacky，但它确实有效。希望有一个更优雅的解决方案...

It's kinda hacky, but it works. Wish there was a more elegant solution...

Class cls = NSClassFromString(@"UIPopoverController");
if (cls != nil)
{
    UIPopoverController *aPopoverController =
        [[cls alloc] initWithContentViewController:self.masterViewController];
    self.popoverController = aPopoverController;

    [aPopoverController release];

    [popoverController presentPopoverFromBarButtonItem:barButtonItem
                              permittedArrowDirections:UIPopoverArrowDirectionUp
                                              animated:YES];
}