显示 Controller 的 iOS 问题

Question

我尝试使用以下代码在我的 View Controller 上显示 PKAddPassesViewController:

[self.helper alert:@"Attenzione" message:@"Grazie per la registrazzione. Ti aspettiamo in uno dei nostri centri Surfree" delegate:self];

//load StoreCard.pkpass from resource bundle
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"surfree" ofType:@"pkpass"];
NSData *data = [NSData dataWithContentsOfFile:filePath];
NSError *error;

//init a pass object with the data
PKPass *pass = [[PKPass alloc] initWithData:data error:&error];

//init a pass library
PKPassLibrary* passLib = [[PKPassLibrary alloc] init];

//check if pass library contains this pass already
if([passLib containsPass:pass]) {

    //pass already exists in library, show an error message
    UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:@"Pass Exists" message:@"The pass you are trying to add to Passbook is already present." delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [alertView show];

} else {

    //present view controller to add the pass to the library
    PKAddPassesViewController *vc = [[PKAddPassesViewController alloc] initWithPass:pass];
    [vc setDelegate:(id)self];
    [self.navigationController pushViewController:vc animated:YES];
    //[self presentViewController:vc animated:YES completion:nil];
}

从逻辑上讲，当调用此行时 ([self.navigationController pushViewController:vc animated:YES];) 我应该看到带有我的存折的 View Controller ，我可以在其中将存折添加到库中，但是它不起作用。我哪里出错了？

编辑:

此外，如果我进行调试，我的路径对象为 nil。

Answer 1

    PKAddPassesViewController *addPassViewController = [[PKAddPassesViewController alloc] initWithPass:newPass];
    addPassViewController.delegate = self;
    [self presentViewController:addPassViewController animated:YES completion:nil];