On Wednesday 14 August 2002 03:47 pm, Jason Dufair wrote:

> I'm not asking for much, am I? :-)  I suspect that I'll need to
> build my own morph, especially to do the last two things.  Can
> anyone give me a suggestion of what to start with for a superclass?

Morph. It's got *plenty* of behavior, believe me.

Or maybe ScrollPane if you want scroll bars. Though the model of the 
ScrollPane pretty much leaves it in charge of translating a number of 
other morphs. If you just want a scroll bar, you might want to just 
add one as an input widget and draw everything else yourself.

I don't think that any of the other Morph subclasses gives you enough 
behavior to matter (unless I'm missing one, there's none that does 
the centered selection and variable transparency).

You'll have to have custom event handling code for keystrokes and 
mouse events.

And you'll have to have a custom drawOn: method to do the 
transparency. Look at the various drawing methods in the Canvas 
subclasses.

A UI question that you'll have to answer:

What happens when someone clicks on a choice that's not in the middle? 
does it suddenly jump to the center and become darker? That would be 
disconcerting...

I'd probably want to make the selected item do a smooth scroll to the 
center, but...

Actually, it sounds pretty simple to implement, with the most 
complicated part being the animations and list drawing logic (where 
to position the entries given a certain list and selection).

-- 
Ned Konz
http://bike-nomad.com
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