Swing and Nimbus: Replace background of JPopupMenu (attached to JMenu)

Question

Nimbus often looks great, but for certain color combinations the result is non-optimal. In my case, the background of a JPopupMenu does not fit, which is why I

Answer 1

not the whole story - but looks like setting the opacity of menu/items to true partly solves it (as @Derek Richard already did for a item created under full application control):

UIDefaults ui = UIManager.getLookAndFeelDefaults();
ui.put("PopupMenu.background", GREEN);
ui.put("Menu.background", GREEN);
ui.put("Menu.opaque", true);
ui.put("MenuItem.background", GREEN);
ui.put("MenuItem.opaque", true);

and so on, for all types of items like radioButton/checkBox.

This still leaves a upper/lower grey area - don't know which part is responsible for that drawing. Removing the margin helps at the price of looking squeezed

// this looks not so good, but without the margins above/below are still grey
ui.put("PopupMenu.contentMargins", null);

There's a list of property keys in the tutorial.