title: Background color of JTextField doesn't become 'grayed out' when disabled after the background color had been changed before
body: <p>Normally when you use <code>setEditable(false)</code> or <code>setEnabled(false)</code>, the background/foreground color of the JTextField becomes 'grayed out'. However, if a background color had previously been set using <code>setBackground(color)</code> (for example to <code>white</code>), then the call to <code>setEnabled</code> or <code>setEditable</code> will not affect the background color anymore. Instead, it is overridden by the previously set color.</p>
  
  <p>In WinForms (.NET) this is solved by "resetting" the background color to a non-overriding default value, namely <code>Color.Empty</code>. That would cause a text box to regain the standard behavior. However, I haven't found a similar "default value" for JTextField. How do I revert the JTextField to use the default colors and automatically switch the color when it is being disabled or set to read only? The foreground color has a similar issue.</p>