For some applications it may be nice if CDockables that share the same data/type/behavior/function/etc
stick together.
Or perhaps another application adds custom placeholders (just a fancy name for "unique identifier") in
the layout, and needs the ability to place new CDockables at the location of said placeholders.
All of this can be achieved with a class called "PlaceholderGrouping":
- Use "CDockable.setGrouping" to define the group in which the element is. You may change the group any time.
- Or use the key "CControl.GROUPING_BEHAVIOR" to define the grouping algorithm for any kind of Dockable.
- The class "PlaceholderGrouping" identifies a group by using a unique identifier called a "placeholder".
- Placeholders are part of the layout, they are persistently stored.