title: Falling Objects Corona
body: <p>I am trying to create a falling objects game. However, I am having hard time to create level for this game. It does not change scene or anything but I want it to be harder along the way. There are bad and good items falling and the character should eat good items and avoid from bad items.</p>
  
  <p>I am creating those bad and good items with a createItem function and calling this function with two timer.performWithDelay. The items are falling randomly. One for the good items and one for the bad items. However, sometimes bad item comes under the good item and it is impossible to catch the good item. How can I stop that? I added a collision filter to let those items pass through each other so that's why they come as one under the another.</p>
  
  <p>Here is how I call createItem with two timers:</p>
  
  <pre><code> goodTimer = timer.performWithDelay(1000, function() createItem(goodItem[math.random(1,#goodItem)],1) end, 0 )
  
   badTimer = timer.performWithDelay(5000, function()  createItem(badItem[math.random(1,#badItem)],0) end, 0 )
  </code></pre>