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?