Question

我很难过。我的应用程序正在使用核心数据来管理玩家并匹配签入。我有两个类，我试图在用户从桌面视图中选择一个玩家时将玩家详细信息添加到匹配项中。

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    Player *selectedPlayer = [self.fetchedResultsController objectAtIndexPath:indexPath];

    checkInPlayer.playerFirstName = selectedPlayer.playerFirstName;
    checkInPlayer.playerLastName = selectedPlayer.playerLastName;
    checkInPlayer.playerImage = selectedPlayer.playerImage;
}

我将checkInPlayer属性设置为等效的selectedPlayer属性时出错。

checkInPlayer是CheckIn的一类，具有以下属性：

@interface CheckIn : NSManagedObject

@property (nonatomic, retain) NSDate * checkInTime;
@property (nonatomic, retain) NSString * firstName;
@property (nonatomic, retain) NSString * lastName;
@property (nonatomic, retain) NSSet *checkInPlayers;
@end

selectedPlayer是Player的一类，具有以下属性：

@interface Player : NSManagedObject

@property (nonatomic, retain) NSString * playerFirstName;
@property (nonatomic, retain) NSString * playerID;
@property (nonatomic, retain) NSString * playerLastName;
@property (nonatomic, retain) NSSet *playerCheckins;
@end

有什么想法吗？

完整错误：

2014-03-17 15:54:17.989 League Manager[2507:60b] -[CheckIn setPlayerFirstName:]: unrecognized selector sent to instance 0x10963b240
2014-03-17 15:54:17.991 League Manager[2507:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[CheckIn setPlayerFirstName:]: unrecognized selector sent to instance 0x10963b240'
*** First throw call stack:
(
    0   CoreFoundation                      0x0000000101f3c495 __exceptionPreprocess + 165
    1   libobjc.A.dylib                     0x0000000101a3c99e objc_exception_throw + 43
    2   CoreFoundation                      0x0000000101fcd65d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
    3   CoreFoundation                      0x0000000101f2dd8d ___forwarding___ + 973
    4   CoreFoundation                      0x0000000101f2d938 _CF_forwarding_prep_0 + 120
    5   League Manager                      0x000000010000907b -[SelectPlayerTVC tableView:didSelectRowAtIndexPath:] + 379
    6   UIKit                               0x00000001006b15c2 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 1312
    7   UIKit                               0x00000001006b16eb -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 221
    8   UIKit                               0x0000000100602100 _applyBlockToCFArrayCopiedToStack + 316
    9   UIKit                               0x0000000100601f71 _afterCACommitHandler + 460
    10  CoreFoundation                      0x0000000101f07dc7 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23
    11  CoreFoundation                      0x0000000101f07d37 __CFRunLoopDoObservers + 391
    12  CoreFoundation                      0x0000000101ee7522 __CFRunLoopRun + 946
    13  CoreFoundation                      0x0000000101ee6d83 CFRunLoopRunSpecific + 467
    14  GraphicsServices                    0x0000000103f6df04 GSEventRunModal + 161
    15  UIKit                               0x00000001005e9e33 UIApplicationMain + 1010
    16  League Manager                      0x0000000100008433 main + 115
    17  libdyld.dylib                       0x00000001025d45fd start + 1
    18  ???                                 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException

Answer 1

您说checkInPlayer属于CheckIn类，但您尝试访问仅在Player课程中声明的属性。您需要在playerFirstName课程中声明相同的属性（CheckIn等），或者您需要将checkInPlayer更改为Player的实例} class。

更清楚的是，它看起来应该更像这样：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    Player *selectedPlayer = [self.fetchedResultsController objectAtIndexPath:indexPath];

    checkInPlayer.firstName = selectedPlayer.playerFirstName;
    checkInPlayer.lastName = selectedPlayer.playerLastName;
    // No such property playerImage in the CheckIn class
    //checkInPlayer.playerImage = selectedPlayer.playerImage;
}

Answer 2

JJC说了什么。

'NSInvalidArgumentException'，原因：' - [CheckIn setPlayerFirstName：]：

但是，CheckinClass在playerFirstName设置了firstName，checkInPlayer.playerFirstName = selectedPlayer.playerFirstName;只有一个属性。

你有：

checkInPlayer.firstName = selectedPlayer.playerFirstName;

应该是：

{{1}}

无法识别的选择器从didSelectRowAtIndexPath发送到实例

2 个答案: