小编Uma*_*raj的帖子

我有带有视图控制器的标签栏控制器,其中只有一个表视图.

我使用代码设置导航栏大标题:

if (@available(iOS 11.0, *)) {
        [[UINavigationBar appearance] setPrefersLargeTitles:YES];
    } else {
        // Fallback on earlier versions
    }

当我第二次打开标签时,它正在崩溃应用程序.或随机移动标签以及以下消息.

错误消息如下所示:

Assertion failure in -[UITableView _addScrollViewScrollObserver:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit/UIKit-3694.4.18/UIScrollView.m:7693

任何解决问题的想法.谢谢.

我在UITableView中的Container视图中使用UISearchController.我正在添加这样的搜索栏:

self.resultsTableController = [self.storyboard instantiateViewControllerWithIdentifier:NSStringFromClass([ResultViewController class])];

self.searchController = [[UISearchController alloc] initWithSearchResultsController:self.resultsTableController];
self.searchController.searchBar.frame = CGRectMake(self.searchController.searchBar.frame.origin.x, self.searchController.searchBar.frame.origin.y, self.searchController.searchBar.frame.size.width, 44.0);
self.searchController.searchResultsUpdater = self;
[self.searchController.searchBar sizeToFit];

self.searchController.hidesNavigationBarDuringPresentation = NO;
self.tableView.tableHeaderView = self.searchController.searchBar;
self.resultsTableController.tableView.delegate = self;
self.searchController.delegate = self;
self.searchController.dimsBackgroundDuringPresentation = YES;
self.searchController.searchBar.delegate = self;
self.definesPresentationContext = NO;

请参阅以下屏幕截图.它隐藏了搜索栏上方的所有搜索结果:

请帮帮我,为什么我得到这个？

我的应用程序在应用程序商店,我已经启用了我的应用程序内的批评.报告崩溃后:

Threads
_________________________________
Thread: Unknown Name (Crashed)
0     libobjc.A.dylib                       0x00000001973f7bdc objc_msgSend + 28
1     UIKit                                 0x000000018b59952c -[UIKeyboardImpl centerFilled] + 88
2     UIKit                                 0x000000018b90eb00 -[UIKBBackgroundView refreshStyleForKeyplane:inputTraits:] + 300
3     UIKit                                 0x000000018b599284 -[UIKeyboardLayoutStar updateBackgroundIfNeeded] + 384
4     UIKit                                 0x000000018b591cc4 -[UIKeyboardLayoutStar setKeyplaneName:] + 2672
5     UIKit                                 0x000000018b4d2f7c -[UIKeyboardLayoutStar setShift:] + 180
6     UIKit                                 0x000000018b4d2ca8 -[UIKeyboardImpl notifyShiftState] + 84
7     CoreFoundation                        0x0000000186c92a50 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 28
8     CoreFoundation                        0x0000000186c8f9dc __CFRunLoopDoObservers + 356
9     CoreFoundation                        0x0000000186c8fd24 __CFRunLoopRun + 680
10   CoreFoundation                         0x0000000186bbd0a4 CFRunLoopRunSpecific + 392
11 …

我呈现的UIViewController是:

UIStoryboard *storyboard  = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];

PhotoViewController *resultVC = [storyboard instantiateViewControllerWithIdentifier:NSStringFromClass([PhotoViewController class])];
[self.navigationController presentViewController:resultVC animated:YES completion:^{}];

我已登录控制台,结果是:

po self.navigationController
<UINavigationController: 0x9c3e920>

但是当我在PhotoViewController课堂上时,我已经记录了控制台,结果是:

po self.navigationController
nil

它在这里没有.我不知道为什么会这样.我也有这个,但它总是:

[self presentViewController:resultVC animated:YES completion:^{}];

我得到和例外:

没有更多上下文,表达式的类型是模糊的

使用以下代码:

struct Parameter { 
    static let Email = "email" 
    static let Password = "password" 
    static let IsFacebookUser = "isFacebookUser" 
}

let parameters : [String : AnyObject] = [Parameter.Email : email, Parameter.Password : password, Parameter.IsFacebookUser : false]

它不接受bool类型,我不想更改我的数据类型.

这段代码有什么问题吗？

NSPredicate *predicate = [NSPredicate 
                             predicateWithFormat:@"todo_category_id IN %@" 
                                   argumentArray:array];

todo_category_id是一个NSNumber-type属性.
array仅包含3个也是NSNumber类型对象的元素.

我想根据这些ID从Core Data中获取类别.

我有NSDictionary值,我想将其转换为Json字符串,如:

{
    body = "10-feb";
    comments =     (
    );
    complete = 1;
    "created_at" = "2014-02-09T15:56:01Z";
    "due_at" = "2014-01-10 20:00:00 +0000";
    "due_on" = "2014-10-02";
    id = 439824;
    "notification_sent" = 0;
    "notify_user" = 0;
    "organization_id" = 972;
    participants =     (
    );
    reminders =     (
    );
    starred = 0;
    "updated_at" = "2014-02-09T15:56:01Z";
    "user_id" = 11129;
}

我将它转换为json的方式是:

- (NSString*) jsonStringWithPrettyPrint:(BOOL) prettyPrint str:(NSDictionary *)str {
    NSError *error = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:str
                                                       options:(NSJSONWritingOptions)    (prettyPrint ? NSJSONWritingPrettyPrinted : 0)
                                                         error:&error];

    if (! jsonData) …