我已经尝试了几个小时,我无法解决这个问题.
我正在制作一个可以保存未完成的国际象棋游戏的应用程序,所以我正在尝试将数组写入文件.
如果有意义的话,这就是数组：
-NSMutableArray savedGames --GameSave a ---NSMutableArray board; ----Piece a,b,c,etc. -----some ints ---NSString whitePlayer,blackPlayer; ---int playerOnTop,turn; --GameSave b ---NSMutableArray board; ----Piece a,turn;
等等
这些是我的NSCoding方法：
GameSave.m
- (void)encodeWithCoder:(NSCoder *)coder {
[coder encodeObject:whitePlayer forKey:@"whitePlayer"];
[coder encodeObject:blackPlayer forKey:@"blackPlayer"];
[coder encodeInt:playerOnTop forKey:@"playerOnTop"];
[coder encodeInt:turn forKey:@"turn"];
[coder encodeObject:board forKey:@"board"];
}
- (id)initWithCoder:(NSCoder *)coder {
self = [[GameSave alloc] init];
if (self != nil)
{
board = [coder decodeObjectForKey:@"board"];
whitePlayer = [coder decodeObjectForKey:@"whitePlayer"];
blackPlayer = [coder decodeObjectForKey:@"blackPlayer"];
playerOnTop = [coder decodeIntForKey:@"playerOnTop"];
turn = [coder decodeIntForKey:@"turn"];
}
return self;
}
Piece.m
- (void)encodeWithCoder:(NSCoder *)coder {
[coder encodeInt:color forKey:@"color"];
[coder encodeInt:piece forKey:@"piece"];
[coder encodeInt:row forKey:@"row"];
[coder encodeInt:column forKey:@"column"];
}
- (id)initWithCoder:(NSCoder *)coder {
self = [[Piece alloc] init];
if (self != nil)
{
color = [coder decodeIntForKey:@"color"];
piece = [coder decodeIntForKey:@"piece"];
row = [coder decodeIntForKey:@"row"];
column = [coder decodeIntForKey:@"column"];
}
return self;
}
- (void)saveGame {
ChessSaverAppDelegate *delegate = (ChessSaverAppDelegate *) [[UIApplication sharedApplication] delegate];
[[delegate gameSave] setBoard:board];
NSMutableArray *savedGames = [NSKeyedUnarchiver unarchiveObjectWithFile:[self dataFilePath]];
if (savedGames == nil) {
[NSKeyedArchiver archiveRootObject:[delegate gameSave] toFile:[self dataFilePath]];
} else {
[savedGames addObject:[delegate gameSave]];
[NSKeyedArchiver archiveRootObject:savedGames toFile:[self dataFilePath]];
}
}
- (NSString *)dataFilePath {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
return [documentsDirectory stringByAppendingPathComponent:@"gameSaves.plist"];
}
对不起,这是问题所在：
设置一些断点后,在-saveGame的这一行之后会出现错误：
[NSKeyedArchiver archiveRootObject：savedGames toFile：[self dataFilePath]];
2010-05-11 17:04:08.852 ChessSaver[62065:207] *** -[NSCFType encodeWithCoder:]: unrecognized selector sent to instance 0x3d3cd30
2010-05-11 17:04:08.891 ChessSaver[62065:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException',reason: '*** -[NSCFType encodeWithCoder:]: unrecognized selector sent to instance 0x3d3cd30'
2010-05-11 17:04:08.908 ChessSaver[62065:207] Stack: (
32339035,31077641,32720955,32290422,32143042,238843,25827,564412,342037,606848,17686,2733061,4646817,3140430,3149167,3144379,2837983,2746312,2773089,41684313,32123776,32119880,41678357,41678554,2777007,9884,9738
)
如果重要,则从导航控制器中的UIBarButton调用-saveGame.
任何帮助表示赞赏,谢谢.
解决方法
这是错的：
- (id)initWithCoder:(NSCoder *)coder {
self = [[Piece alloc] init];
if (self != nil)
{
当initWithCoder：被调用时,已经分配了类的实例.在您的代码中,您正在泄漏该实例.你应该这样做：
- (id)initWithCoder:(NSCoder *)coder {
self = [super init]; // or [self init] if needed
if (self != nil)
{
此外,当您解码对象时,您不拥有它,因此您需要保留它.
board = [[coder decodeObjectForKey:@"board"] retain];
如果你没有“获得”保留/释放规则,现在就学习它们,否则你将不断地用脚射击.
此外,您的saveGame方法有几个问题.
>如果savedGames为nil,则表示您将对象而非数组保存到文件中.这意味着在下次运行时,未归档的对象将不是您期望的数组.
>未归档的数组是不可变的.将类型声明为NSMutableArray并不重要,如果归档可变数组,则将在unarchive上获得不可变数组.如果要修改它,则需要在unarchived数组上调用mutableCopy.
我完全不确定异常,但是修复了上述问题,要么它会消失,要么解决方案会变得更容易找到.