title: I can't see any of the buttons, or the background (Corona SDK)
body: <p>I'm trying to make a game for the Android Google Play store.  But, when I was making the main menu I ran into an issue.</p>
  
  <p>Before I added the storyboard and the scene functions, everything worked fine.  But now I can't see a thing when I run it.</p>
  
  <p>Also, I get no errors.</p>
  
  <pre><code>    -- Requires
  
      local widget = require "widget"
  
      local storyboard = require ("storyboard")
      local scene = storyboard.newScene()
  
      function scene:createScene(event)
  
  screenGroup = self.view
  
  -- Background
  local background = display.newImage("images/bg.png")
  screenGroup:insert(background)
  
  -- Title
  local title = display.newImage("images/title.png")
  title.x = display.contentCenterX
  title.y = display.contentCenterY - 110
  screenGroup:insert(title)
  
  -- Play game
  local button1 = widget.newButton {
  
      label = "Play Game",
      font = default,
      fontSize = 24,
      width = 200,
      height = 50
  
  }
  button1.x = display.contentCenterX
  button1.y = display.contentCenterY - 47
  screenGroup:insert(button1)
  
  -- How To Play
  local button2 = widget.newButton {
  
      label = "How To Play",
      font = default,
      fontSize = 24,
      width = 200,
      height = 50
  
  }
  button2.x = display.contentCenterX
  button2.y = display.contentCenterY + 13
  screenGroup:insert(button2)
  
  -- Level Select
  local button3 = widget.newButton {
  
      label = "Level Select",
      font = default,
      fontSize = 24,
      width = 200,
      height = 50
  
  }
  button3.x = display.contentCenterX
  button3.y = display.contentCenterY + 73
  screenGroup:insert(button3)
  
  -- About Us
  local button4 = widget.newButton {
  
      label = "About Us",
      font = default,
      fontSize = 24,
      width = 200,
      height = 50
  
  }
  button4.x = display.contentCenterX
  button4.y = display.contentCenterY + 133
  screenGroup:insert(button4)
  
      end
  
      function start(event)
  if event.phase == "began" then
      storyboard.gotoScene("level1", "fade", 400)
  end
      end
  
      function scene:enterScene(event)
  button1:addEventListener("touch", start)
      end
  
      return scene
  </code></pre>