private void computeContents() {
ButtonGroup bgroup = new ButtonGroup();
bgroup.add(nullItem);
removeAll();
add(minimize);
add(zoom);
add(close);
if (!persistentItems.isEmpty()) {
addSeparator();
for (JRadioButtonMenuItem item : persistentItems) {
bgroup.add(item);
add(item);
}
}
if (!transientItems.isEmpty()) {
addSeparator();
for (JRadioButtonMenuItem item : transientItems) {
bgroup.add(item);
add(item);
}
}
WindowMenuItemManager currentManager = WindowMenuManager.getCurrentManager();
if (currentManager != null) {
JRadioButtonMenuItem item = currentManager.getMenuItem(this);
if (item != null) {
item.setSelected(true);
}
}
}
void computeEnabled() {
WindowMenuItemManager currentManager = WindowMenuManager.getCurrentManager();
minimize.setEnabled(currentManager != null);
zoom.setEnabled(currentManager != null);
close.setEnabled(currentManager != null);
}