title: Add JScrollPane to a JPanel
body: <p>I have this interface to create. I have a problem with the JScrollPane:</p>
  
  <p><img src="https://i.stack.imgur.com/gJ6GU.png" alt="enter image description here"></p>
  
  <p>I declared a JPanel with a Gridlayout(8,1,0,2), I want 8 rows appear in this panel.
  A row is a JPanel to, I set the size to make the 8 row panels appear in the big panel.
  If the number of rows pass 8, I get two columns ...
  I added a JScrollPane but it doesn't appear.
  Testing button at the place of button, the scrollpane appear but returning to panel it disappear..</p>
  
  <p>How can I do ??</p>