UIManager.put ("Panel.opaque", false); does not work

Question

Setting UIManager.put ("Panel.opaque", false); does not work. I need to call panel.setOpaque (false); for each panel.

what could be the problem?

Answer 1

You can create your own JPanel class and use it instead of JPanel.

 class MyJPanel extends JPanel{ public MyJPanel(){ setOpaque(false); } } 

Answer 2

Why not use JComponent instead? The default is opaque .

Answer 3

I do not see this constant when I do

  UIDefaults defaults = UIManager.getLookAndFeelDefaults(); Set<Entry<Object, Object>> entries = defaults.entrySet(); for (Entry<Object, Object> entry : entries) { System.out.print(entry.getKey() + " = "); System.out.print(entry.getValue() + "\n"); 

Answer 4

Since the method deals with default values, you need to put it at the very beginning of your program for it to work, or, possibly, before calling other GUI-related methods. The only thing that should have happened before was the locale.