EXC_BAD_ACCESS cocos2d - box2d

Question

我正在抛出一个对象（box2d），但是当我尝试进行碰撞检测时，它会在该对象的CGRect上给出错误。见下图

这就是我创建对象主体的方式

-(void) createObject
{
    freeBodySprite = [CCSprite spriteWithFile:@"object.png"];
    //freeBodySprite.position = ccp(100, 300);
    [self addChild:freeBodySprite z:2 tag:6];

    CGPoint startPos = CGPointMake(150, 320/1.25);

    bodyDef.type = b2_staticBody;
    bodyDef.position = [self toMeters:startPos];
    bodyDef.userData = freeBodySprite;


    float radiusInMeters = ((freeBodySprite.contentSize.width * freeBodySprite.scale/PTM_RATIO) * 0.5f);
    shape.m_radius = radiusInMeters;


    fixtureDef.shape = &shape;
    fixtureDef.density = 0.02f;
    fixtureDef.friction = 1.0f;
    fixtureDef.restitution = 0.0f;

    circularObstacleBody = world->CreateBody(&bodyDef);
    stoneFixture = circularObstacleBody->CreateFixture(&fixtureDef);
    freeBody = circularObstacleBody;

}

Answer 1

可能你正在丢失freeBodySprite内存参考。

尝试将其创建为retain属性，并始终在代码中使用self.freeBodySprite。

@property (nonatomic, retain) CCSprite *freeBodySprite;

...

self.freeBodySprite = [CCSprite spriteWithFile:@"object.png"];

... 

self.freeBodySprite.position.x;

Answer 2

我有一个计时器，每0.01秒安排一次。我正在触摸端上制作freebody = nil，所以每当它为零且我的计时器方法运行时它就给了我这个错误。