[wiki:Development]



= Old notes =



== Ideas ==

 * let widgets manage themselfs
 * There a three kind of widgets:
   1. basic widgets that do not contain other widgets
   1. layout widgets that contain several wigets
   1. frame widgets that contain exactly one layout widget

 * Layouts in other widget sets
   * arrage subwidgets
   * tell surrounding widget how many space is needed
   * may be applied to basic widgets to control their size


== Controling size ==

Ideas stolen from Qt
 
 * widget methods
   * sizeHint (prefered size)
   * minimumSize
   * maximumSize
   * hasHeightForWidth (bool == FlowWidget)
   * heightForWidth(width) -> heigth (==rows())
 * Size policy flags (can be combined) two set of flags (v and h)
   * grow - may be bigger but does improve the widget
   * expand - more space is useful 
   * shrink - may be smaller
   * ignore - don't use sizeHint()
 * "weight" (h/v) (named "stretch" in Qt)

Gtk has a "fill" flag. Having "expand" only allocates empty space while "fill" force the widget to acually use it. That way no fillers are needed. (JFYI)

== widget containers ==

What to do with .item_types? (per-item layout information in Pile and Columns widgets)
The layout information is specific to pile and columns, so I don't know how useful
it would be to give it back to the user when they are querying contained widgets.

 * Move this into the widget - see above

Perhaps it would suffice to have a different interface for this data as long as Pile
and Columns do the right thing when a user of the container interface inserts or
deletes items.

!ListBox will be a problem, it may display unbounded/lazily generated data.  If the
!SimpleListWalker is used there is no problem..  exend the list walker interface to 
include the container interface?

 * Should be easy for the !SimpleListWalker as it already uses a list.
 * Some special !ListWalkers (like the fibonacci one) don't need to be containers

 * .getChildByPosition(self, size, col, row)