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我有一个从 XCode 模板UISplitViewController中实现 amasterNavigationController和 a 的基本。detailNavigationController

masterNavigationController调用另一个NSObject称为“API”的 API,该 API 又用于从ASIHTTPRequest服务器检索某些 JSON 数据。

一切都很好,花花公子,直到我从请求开始。它显示 iPad 的图形用户界面,并在使用EXC_BAD_ACCESS. 我收到的错误消息如下:

2012-10-10 21:13:42.357 myapp[24409:c07] Splitview 控制器在使用前应该在索引 0 处有一个视图控制器!

我尝试了不同的方法来尝试解决这个问题,其中之一是在设置视图控制器之后设置 SplitViewController 委托,另一个是使用 NetworkQueue。

这是的代码masterNavigationController

[...]
- (void)viewDidLoad
{
    [UIHelper setNavigationBackBackground:self.navigationController.navigationBar widePage:NO];
    [UIHelper setViewBackground:self.parentViewController.view widePage:NO];
    [UIHelper setTableViewStyle:self.tableView];

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.navigationItem.leftBarButtonItem = self.editButtonItem;

    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(insertNewObject:)];
    self.navigationItem.rightBarButtonItem = addButton;

    API *api = [[API alloc] init];
    [api setDelegate:self];
    [api setDidFinishSelector:@selector(didFinish:)];
    [api getCommingRetrievals];
}
[...]

AppDelegate:

[...]
    MasterViewController *masterViewController = [[MasterViewController alloc] initWithStyle:UITableViewStylePlain];
    UINavigationController *masterNavigationController = [[UINavigationController alloc] initWithRootViewController:masterViewController];

    DetailViewController *detailViewController = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil];
    UINavigationController *detailNavigationController = [[UINavigationController alloc] initWithRootViewController:detailViewController];

    masterViewController.detailViewController = detailViewController;

    self.splitViewController = [[UISplitViewController alloc] init];

    self.splitViewController.view.opaque = NO;
    self.splitViewController.view.backgroundColor = [UIColor clearColor];

    self.splitViewController.viewControllers = @[masterNavigationController, detailNavigationController];
    masterViewController.managedObjectContext = self.managedObjectContext;

    self.splitViewController.delegate = detailViewController;

    self.window.rootViewController = self.splitViewController;
    [self.window makeKeyAndVisible];
[...]

这是 API 对象的代码:

- (void)getCommingRetrievals
{
    [self getRetrievalsForDate:[NSDate date]];
}

- (void)getRetrievalsForDate:(NSDate*)date
{
    NSString *stringFromDate = @"";

    if (date != nil)
    {
        // Set date string
        NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
        [formatter setDateFormat:@"yyyyMMdd"];
        stringFromDate = [formatter stringFromDate:date];
    }

    NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"%@/bookings/%@", API_BASE_DOMAIN, stringFromDate]];
    [self callApi:url requestMethod:@"GET"];
}

#pragma mark - 
#pragma mark API methods

- (void)callApi:(NSURL*)url requestMethod:(NSString*)requestMethod
{
    ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url];
    [request setRequestMethod:requestMethod];
    [request setDelegate:self];
    [request setDidFinishSelector:@selector(requestFinished:)];
    [request setDidFailSelector:@selector(didFailWithError:)];
    [request startAsynchronous];
}

- (void)requestFinished:(ASIHTTPRequest *)request
{
    if (self.delegate && [self.delegate respondsToSelector:didFinishSelector]) {
        [self.delegate performSelector:didFinishSelector withObject:self];
    }
}

如果我注释掉该行[request startAsynchronous];,应用程序不会崩溃。

我在这里缺少什么,我该如何解决这个问题?

4

1 回答 1

1

检查您的 UISplitViewController 是否已通过 2 个视图控制器。

除此之外,还有一些惯用的东西:

这应该在任何设置的开始时进行:

[super viewDidLoad];

例如`[super viewDidLoad]` 约定

并考虑使用 ASI 以外的其他框架。这是一个死图书馆。AFNetworking、MKNetworkingKit 或 RESTKit 是不错的选择。

于 2012-10-10T19:37:52.793 回答