[Dynapi-Dev] (no subject)

[Scott A. L. <sc...@sc...>]

I think I've found a fix for the problem with children arrays being shared
between widgets made with the widgetX  model.

The problem:

Widget.prototype = new DynLayer()

When this is done, the properties of the base DynLayer are *shared* with
every Widget made with the constructor.

Most of these shared properties are reassigned to unique ones when
createElement is called on the Widget.  However, the children array is not,
and it gives the effect that all Widgets share the same children array.

So I've posted a patch for DynLayer and DynDocument that assigns the
this.children array only when you use addChild.  DynLayer-based widgets
won't have a children array until you add at least one child.

I also made changes to removeChild, removeAllChildren, etc. that check for
the existence of the child array before proceeding.

This should ensure that the children array is a unique object for each
widget, and not the common one in the Widget prototype.  Then you can safely
use WidgetX to simulate inheritance without the shared-properties problem.

The only consideration is if you build a widget that manipulates the
children array, you should test it it exists first (it's initially set to
null until you use addChild).

I've only tested it on a few IBS and GUI widgets, but it seems to work
across the board.  I've posted the patch for review.

scottandrew






------
Scott Andrew LePera
DHTML / Scripting / CGI and other neat stuff
sc...@sc...
http://www.scottandrew.com