在ZBar委托方法中以模态方式呈现视图

Question

我正在使用ZBar开发QR码阅读器应用程序。我正在使用XCode 4.2

这是我的代码，我在成功扫描QR码后以模态方式呈现另一个视图，但它不起作用：

- (void) imagePickerController: (UIImagePickerController*) reader
 didFinishPickingMediaWithInfo: (NSDictionary*) info
{
    // ADD: get the decode results
    NSString *test3=@"test";

    id<NSFastEnumeration> results =
    [info objectForKey: ZBarReaderControllerResults];
    ZBarSymbol *symbol = nil;
    for(symbol in results){
    theBarcodeString = symbol.data;
    if ([theBarcodeString isEqualToString:test3]){
        nextView *next ;   
        next= [[nextView alloc] initWithNibName:nil bundle:nil];
        [self presentModalViewController:next animated:YES];
    }
    }
    // ADD: dismiss the controller (NB dismiss from the *reader*!)

    [reader dismissModalViewControllerAnimated: YES];   
}