bodyWithBodies SKPhysicsBody

Question

在解释如何有效地实现这个类方法时，Apple的文档是模糊的

+ (SKPhysicsBody *)bodyWithBodies:(NSArray *)bodies; //the error that I'm getting is 2014-04-23 23:25:21.518 Space Monkey[3398:60b] -[SKSpriteNode _shapes]: unrecognized selector sent to instance 0x15d79c50

2014-04- 23 :25:21.520 SpaceMonkey3398:60B *终止应用程序因“NSInvalidArgumentException”异常而终止，原因：'-SKSpriteNode _shapes:未识别的选择器发送到实例0x15d79c50‘*第一次抛出调用堆栈：(0x2d92ef0x380c3ce7 0x2d92837 0x2d93112f.这是抛出一个例外，我几乎已经研究了到处没有运气。关于同样的问题，这里还有另一个问题，然而，这些建议似乎根本行不通。我提供了代码，以便有人能给我一些启示，希望能给我正确的指导.这是代码

-(NSMutableArray *)platformBars
 {
   NSMutableArray *array =[[NSMutableArray alloc]init];
   //_spriteNode declared in the interface as an instance variable
   _spriteNode=[SKSpriteNode node];
   for (int i =0; i<5; i++)
      {
        _spriteNode= [SKSpriteNode spriteNodeWithImageNamed:@"Water Block"];
        _spriteNode.physicsBody.mass = 10.0f;
        _spriteNode.physicsBody.density = _spriteNode.size.height;
        _spriteNode.position = CGPointMake(x , _spriteNode.position.y);
        x=x+40;
        [array addObject:_spriteNode];
      }
      return array;
  }

-(PlatformNode *)createPlatformsAtPosition:(CGPoint)position
 {
   NSArray *arrays = [self platformBars];
   PlatformNode *node =[PlatformNode node];
   node.physicsBody = [SKPhysicsBody bodyWithBodies:arrays];
   for (SKSpriteNode *sknode in arrays)
       {
         [node addChild:sknode];
       }
   node.position=position;
   node.name    =@"platform";
   node.physicsBody.affectedByGravity  = NO;
   NSLog(@"bodyofSize %f",[node calculateAccumulatedFrame].size.width);
   return node;
  }

  -(PlatformNode *)createPlatformsAtPosition:(CGPoint)position is called in the  
  -(void)didMoveToView:(SKView *)view body of the function. 

我希望我包括了足够的细节和我的代码片段，所以希望有人会帮助我和其他人来。提前谢谢你。

Answer 1

应该是

NSArray *arrays = [[self platformBars] copy];

而不是

NSArray *arrays = [self platformBars];

因为[self platformBars]是可变数组，而arrays是不可变的。

编辑

而且，数组中的SKSpriteNode，而不是物理体。所以

node.physicsBody = [SKPhysicsBody bodyWithBodies:arrays];

应该是

NSMutableArray *mArray=[NSMutableArray new];
for (SKSpriteNode *anySpriteNode in arrays){
[mArray addObject:anySpriteNode.physicsBody];
}
node.physicsBody = [SKPhysicsBody bodyWithBodies:mArray.copy];