Question

所以在MyScene.m我创建了我的Balloon对象并将其放入场景中。

for (int i = 0; i < 4; i++) {

    Balloon *balloonObject = [[Balloon alloc] init];
    balloonObject.position = CGPointMake(50 + (75 * i), self.size.height*.5);
    [_balloonsArray addObject:balloonObject];
}

while (_balloonsArray.count > 0) {
    [self addChild:[_balloonsArray objectAtIndex:0]];
    [_balloonsArray removeObjectAtIndex:0];
}

这让我在屏幕上显示了4个气球。在Balloon.h文件中，我有一个名为-(void)shrink的方法，我想在-(void)touchesBegan方法中的tapped balloonObject上调用它。我在下面尝试过这段代码，但它给了我一个NSInvalidArgumentException', reason: '-[SKSpriteNode shrink]: unrecognized selector sent to instance 0x17010c210'错误。

for (UITouch *touch in touches) {
        CGPoint location = [touch locationInNode:self];
        Balloon *node = (Balloon *)[self  nodeAtPoint:location];

        if ([node.name isEqualToString:@"balloon"]) {

            [node shrink];
        }
}

Balloon.h

@interface Balloon : SKSpriteNode

-(void)shrink;

@end

Balloon.m

@implementation Balloon
{
    SKSpriteNode *_balloon;
}

-(id)init{

    self = [super init];
    if (self){
        _balloon = [SKSpriteNode spriteNodeWithImageNamed:@"balloonPicture"];
        _balloon.name = @"balloon";
        _balloon.position = CGPointMake(0, 0);

        [self addChild:_balloon];
    }

    return self;
}

-(void)shrink{

    // does something
}

Answer 1

问题出在你的气球初始化中。您正在创建子SKSpriteNode并将名称设置为气球，而不是使用Balloon类。这就是你获得SKSpriteNode而不是气球的原因。

你可以这样做。

-(id)init{

    self = [super init];
    if (self){

        self.texture = [SKTexture textureWithImageNamed:@"balloonPicture"];
        self.size = self.texture.size;
        self.name = @"balloon";
        self.position = CGPointMake(0, 0);
    }

    return self;
}

在您创建气球的场景中

Ballon *balloon = [[Balloon alloc]init];
[self addChild:balloon];

触摸时如何在touchesBegan中调用对象的方法？

1 个答案: