Hi Lukas, Thanks for the info. It is indeed more complex than it seems. Would it help if a description has a unique name within a MAContainer? So a container would have an ordered dictionary of children instead of an ordered collection. Jan. On Mon, Sep 19, 2011 at 7:24 AM, Lukas Renggli <renggli(a)gmail.com> wrote:

I've used custom properties extensively and are a big part of what I have been doing lately. Don't be afraid to add a property by which YOUR code can identify another description. Just add them in your own package. I don't think you will ever get around iterating through a description to find the one you're after. But you can use another property to store the found description, so it optimizes... I wrestled for some time with finding a way to allow descriptions in a container to "communicate" with one another. Its kind of basic to what we want to use objects for, if one field changes another needs to know about it. But in the memento world, these rules that we might put in a setter method are of no use because they will not execute until the memento is committed. So I came up with an api of sorts, a set of properties, that give you a way to link descriptions together so that components built knowing about these properties can handle events and perform needed operations *on the memento*. It works well with with JQuery. Still quite a work in progress (i.e. it's really ugly code right now) but its in the Magritte-JQueryWidgetBox package in the Magriite 2 addons repository<http://source.lukas-renggli.ch/@MQPvXVc6Gb8CgywA/UWuv1AEz?64>if you have the stomach for it :) I removed the widget box components from the functional test so it could run in a stock Seaside 3.0 image. The functional test is the only test in the package btw, ahem 8] Anyway, I've stayed up too late bragging about my crap, but it shows what can be done with custom properties. John On Mon, Sep 19, 2011 at 11:07 AM, Yanni Chiu &lt;yanni(a)rogers.com&gt; wrote: