title: cocos2D CCLayer or CCLayerColor setOpacity
body: <p>I'm trying to animate the opacity of a CCLayerColor and its not working. Here are my efforts so far. I've defined retryMenuLayer in .h like</p>
  
  <pre><code>CCLayerColor *retryMenuLayer;
  </code></pre>
  
  <p>and in .m file</p>
  
  <pre><code>retryMenuLayer = [CCLayerColor node];
  [self addChild:retryMenuLayer z:5];
  
  retryMenuLayer.scale = 0.5;
  [retryMenuLayer setOpacity:0];
  </code></pre>
  
  <p>and in appearing method, I'm calling this.</p>
  
  <pre><code>[retryMenuLayer runAction:[CCFadeIn actionWithDuration:1]];
  
  //OR
  
  [retryMenuLayer setOpacity:255];
  </code></pre>
  
  <p>What happens is the background of retryMenuLayer animates from transparent to solid black but the contents inside (its children - a Menu with buttons) doesn't animate. In fact I have to use visibility property to at least disappear until the method is called.</p>
  
  <pre><code>retryMenuLayer.visible = NO; // When initiating.
  retryMenuLayer.visible = YES; // When need to appear the layer.
  </code></pre>