ios - 从 didSelectRowAtIndexPath 发送到实例的无法识别的选择器

Question

我被这个难住了。我的应用程序使用核心数据来管理玩家和比赛签到。我有这两个类，并尝试在用户从表格 View 中选择玩家时将玩家详细信息添加到比赛中。

- (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;
}

当我将 checkInPlayer 属性设置为其等效的 selectedPlayer 属性时出现错误。

checkInPlayer 是 CheckIn 的一个类，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 的一个类，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

您说您的 checkInPlayer 属于 CheckIn 类，但您正试图访问仅在您的 Player 类中声明的属性。您需要在 CheckIn 类中声明这些相同的属性(playerFirstName 等)，或者您需要将 checkInPlayer 更改为是 Player 类的实例。

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;
}