title: libgdx scrollpane doesn't display
body: <p>I'm having issues getting libgdxs scrollpane control to work. The code below shows control setup for a simple layout with a label, a List of items inside a scrollpane, and a button. The problem is my scroll pane doesn't show anything other than the vScroll/vScrollKnob ninepatch (that tiny white square) 
  it just looks like this:</p>
  
  <p><a href="http://i.imgur.com/EJKqgXL.png" rel="nofollow">screenshot</a>.</p>
  
  <pre><code>        private void setupLayout()
  {
      String[] listEntries = {"1","2","3","4","5"};
      ListStyle listStyle = new ListStyle();  
      NinePatch example = new NinePatch(new Texture(Gdx.files.internal("data/example.9.png")));       
      listStyle.selectedPatch = example;
      listStyle.font = new BitmapFont();
      mList = new List(listEntries,listStyle);
  
      ScrollPaneStyle paneStyle = new ScrollPaneStyle();
      paneStyle.vScroll = example;
      paneStyle.vScrollKnob = example;        
      mListScroll = new ScrollPane(mList,paneStyle);
      mListScroll.setScrollingDisabled(true, false);
      mListScroll.width = 500;
      mListScroll.height = 500;
  
      LabelStyle ls = new LabelStyle();
      ls.font = new BitmapFont();
      ls.fontColor = new Color(1.0f, 1.0f, 1.0f, 1.0f);
      mLabel = new Label("Label", ls);    
  
      TextButtonStyle buttonStyle = new TextButtonStyle();
      buttonStyle.font = new BitmapFont();
      mButton = new TextButton("Button",buttonStyle);
  
      Table table = new Table();
      table.add(mLabel);
      table.row();
      table.add(mButton);
      table.row();
      table.add(mListScroll);
      mStage.addActor(table);
  }
  </code></pre>
  
  <p>It works as expected if i don't user the scroll pane and add the list directly to the table like this:</p>
  
  <pre><code>    Table table = new Table();
      table.add(mLabel);
      table.row();
      table.add(mButton);
      table.row();
      table.add(mList);             //changed mListScroll(scrollpane class) to mList(List class)
      mStage.addActor(table);
  </code></pre>
  
  <p><a href="http://imgur.com/lwkCTFp.png" rel="nofollow">screenshot</a></p>
  
  <p>But then it will extend out the bottom of my screen when there are too many items. What am I doing wrong here? Is there another parameter i need to set on the scrollpane?</p>