Cocos2d iphone 使用NSKEYEDUNACHIVER加载保存状态时执行错误访问
我对一个Cocos2d iphone 使用NSKEYEDUNACHIVER加载保存状态时执行错误访问,cocos2d-iphone,nsuserdefaults,exc-bad-access,nskeyedunarchiver,Cocos2d Iphone,Nsuserdefaults,Exc Bad Access,Nskeyedunarchiver,我对一个CCSprite进行了子类化,以生成一个可以编码和解码的对象。我想保存精灵状态并在特定位置再次加载。除了使用NSKeyedUnarchiver进行解码(请参见下面的LoadiconScriteState)之外,一切似乎都很正常,它提供了EXC\u BAD\u访问权限下面是代码: HelloWorldLayer.h @interface CCIconSprite : CCSprite { NSString *iconName; float iconXPos; float
CCSprite
进行了子类化,以生成一个可以编码和解码的对象。我想保存精灵状态并在特定位置再次加载。除了使用NSKeyedUnarchiver
进行解码(请参见下面的LoadiconScriteState
)之外,一切似乎都很正常,它提供了EXC\u BAD\u访问权限
下面是代码:
HelloWorldLayer.h
@interface CCIconSprite : CCSprite {
NSString *iconName;
float iconXPos;
float iconYPos;
}
@property (nonatomic, retain) NSString *iconName;
@property (nonatomic, assign) float iconXPos;
@property (nonatomic, assign) float iconYPos;
+ (id)iconWithType:(NSString*)imageName;
- (id)initWithIconType:(NSString*)imageName;
@end
@interface HelloWorldLayer : CCLayer < NSCoding>
{
CCIconSprite* testSprite;
BOOL savedState;
CGSize size;
CCMoveTo* moveTo;
NSMutableArray* saveSpriteArray;
NSData* savedSpriteData;
}
+(CCScene *) scene;
@end
编码和解码:
- (id)initWithCoder:(NSCoder *)decoder {
NSString* imageFileName = [decoder decodeObjectForKey:@"imageFileName"];
self = [self initWithIconType:imageFileName];
if (!self) return nil;
self.iconXPos = [decoder decodeFloatForKey:@"iconXPos"];
self.iconYPos = [decoder decodeFloatForKey:@"iconYPos"];
return self;
}
- (void)encodeWithCoder:(NSCoder *)encoder
{
[encoder encodeObject:iconName forKey:@"imageFileName"];
[encoder encodeFloat:self.iconXPos forKey:@"iconXPos"];
[encoder encodeFloat:self.iconYPos forKey:@"iconYPos"];
}
@end
HelloWorldLayer实现:
@implementation CCIconSprite
@synthesize iconXPos;
@synthesize iconYPos;
@synthesize iconName;
+ (id)iconWithType:(NSString*)imageName
{
return [[[[self class] alloc] initWithIconType:imageName] autorelease];
}
- (id)initWithIconType:(NSString*)imageName
{
self = [super initWithFile:imageName];
if (!self) return nil;
iconName = imageName;
self.position = ccp(iconXPos, iconYPos);
return self;
}
@implementation HelloWorldLayer
+(CCScene *) scene
{
CCScene *scene = [CCScene node];
HelloWorldLayer *layer = [HelloWorldLayer node];
[scene addChild: layer];
return scene;
}
-(id) init
{
if( (self=[super init]) ) {
self.scale = 0.5;
savedState = NO;
size = [[CCDirector sharedDirector] winSize];
testSprite = [CCIconSprite spriteWithFile:@"Icon.png"];
testSprite.position = ccp(size.width/4, size.width/4);
testSprite.anchorPoint = ccp(0,0);
[self addChild:testSprite];
moveTo = [CCMoveTo actionWithDuration:3 position:ccp(3*size.width/4, 3*size.width/4)];
[testSprite runAction:moveTo];
[self schedule:@selector(saveAndLoadSpriteState)];
}
return self;
}
保存和加载状态:
-(void)saveIconSpriteState {
saveSpriteArray = [[NSMutableArray alloc] init];
[saveSpriteArray addObject:testSprite];
savedSpriteData = [NSKeyedArchiver archivedDataWithRootObject:saveSpriteArray];
}
-(void)loadIconSpriteState {
[NSKeyedUnarchiver unarchiveObjectWithData:savedSpriteData];
}
-(void)saveAndLoadSpriteState {
if ((testSprite.position.x > size.width/2) && !savedState) {
savedState = YES;
[self saveIconSpriteState];
}
else if ((testSprite.position.x == 3*size.width/4) && savedState) {
savedState = NO;
[self loadIconSpriteState];
[testSprite runAction:moveTo];
}
}
@end
编辑
设置异常断点后,我得到了以下错误
Assertion failure in -[CCIconSprite initWithFile:]
指向行中的行:
NSAssert(filename != nil, @"Invalid filename for sprite");
在
-(id) initWithFile:(NSString*)filename
CCSprite.m类的方法。只是一种预感,但可能就是这样。当解码字符串时,您应该复制它,因为此时您不拥有它,也没有将它指定给strong或copy属性
- (id)initWithCoder:(NSCoder *)decoder {
NSString* imageFileName = [[decoder decodeObjectForKey:@"imageFileName"] copy];
self = [self initWithIconType:imageFileName];
if (!self) return nil;
...
}
如果不是这样,请设置一个断点,并在编码和解码时验证字符串是否正确 它到底在哪里坠毁?如果尚未启用异常断点,请启用该断点。您是否单步查看imageName是否正确编码/解码?您是否知道您正在使用self.position=ccp(iconXPos,iconYPos);在解码Iconxypo之前?你为什么不使用ARC?请做@LearnCos2D:请查看我添加的编辑。我还按照您的建议启用了ARC。关于位置,在使用它们之前我应该如何解码它们?我必须承认,我不太确定我是如何处理这些位置的。你应该设置self.position=ccp(iconXPos,iconYPos);读取变量后,在initWithCoder中。我意识到我在
testSprite
上使用的是+(id)spriteWithFile:(NSString*)filename
,而不是+(id)iconWithType:(NSString*)imageName
,因此imageFileName
是nil
。现在可以用了,谢谢。但是现在我想保存上面的HelloWorldLayer
的状态,这将如何实现?我是否需要从CCLayer
中创建子类?