objective-c - 如何在Cocos2d中实现精灵的触摸消失？

Question

我正在用cocos2d开发一款iPhone2d游戏，其中设置有很多小精灵。我想通过触摸两个类似的精灵的方式，将它们两个都隐藏起来，我如何能够实现这种效果呢？

原问题：How can I detect touch in cocos2d?

Answer 1

答：Jonas
（最佳答案）
在含有精靈的layer中，你需要輸入：

self.isTouchEnabled = YES;

然後，你可以使用在UIView中的相同event，但是它們被呼叫的方法不同：

- (void)ccTouchesBegan:(NSSet*)touches withEvent:(UIEvent*)event
{
   UITouch* touch = [touches anyObject];
  //in your touchesEnded event, you would want to see if you touched
  //down and then up inside the same place, and do your logic there.
}

---

答：Terence
想要實現這種效果，可以為精靈設定定界框（bounding box），在下述程式碼中，我將所有精靈都置於NSMutableArray中，並檢查它們是否處於定界框內，同時要保證已經初始化觸摸操作：

- (BOOL)ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event 
{
  CGPoint location = [self convertTouchToNodeSpace: touch];

  for (CCSprite *station in _objectList)
  {
    if (CGRectContainsPoint(station.boundingBox, location))
    {
      DLog(@"Found sprite");
      return YES;
    }
  }

  return NO;
}

---

答：David Higgins
根據Jonas的回答，我又做了進一步的改進：

- (void)ccTouchesBegan:(NSSet*)touches withEvent:(UIEvent*)event
{
   UITouch* touch = [touches anyObject];
   CGPoint location = [[[Director sharedDirector] convertCoordinate: touch.location];
   CGRect particularSpriteRect = CGMakeRect(particularSprite.position.x, particularSprite.position.y, particularSprite.contentSize.width, particularSprite.contentSize.height);
   if(CGRectContainsPoint(particularSpriteRect, location)) {
     // particularSprite touched
     return kEventHandled;
   }
}

你可能需要調整x/y的位置，確保精靈的「中心位置」。

---

答：John
David的程式碼在Cocos 0.7.3和2.2.1上，會出現錯誤訊息，所以我用CGRectMake取代CGMakeRect，用[touch locationInView:touch.view]修正了[touch location]的錯誤：

- (BOOL)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch * touch = [touches anyObject];

    CGPoint location = [[Director sharedDirector] convertCoordinate: [touch locationInView:touch.view]];
    CGRect myRect = CGRectMake(sprite.position.x, sprite.position.y, sprite.contentSize.width, sprite.contentSize.height);


    if(CGRectContainsPoint(myRect, location)) {
        // particularSprite touched
        return kEventHandled;
    }
}