If the READ-ONLY attribute of an editor or fill-in widget is TRUE, the widget cannot be enabled for input and its screen value cannot be changed from the user interface.
If the READ-ONLY attribute for a browse widget is TRUE, you cannot update editable cells. If it is set to false, then the ability to edit cells is restored. This functionality only applies to columns that have been enabled in the DEFINE BROWSE statement.
For combo-box browse columns, this attribute is read-only and always returns FALSE.
If the READ-ONLY attribute of a menu item is TRUE, the menu item cannot be chosen. You can set this attribute for a menu item only before the widget is realized.
The READ-ONLY attribute has no effect on the appearance of a widget. If an editor or menu item is insensitive, it is grayed out in some environments. Use the READ-ONLY attribute instead to make the widget insensitive without being grayed out.