[Seaside] WACompound: creating Seaside Widgets

[Nick Ager]

Hi,

I want to build a widget for latitude, longitude entry ([N|S], lat
degrees, lat minutes; [E|W] long degrees, long minutes). Looking at
examples in Seaside it appears I have at least two ways of proceeding:
1) Derive from WAComponent eg WADateSelector
2) Derive from WACompound eg WADateInput

In my application I'll be using the latitude and longitude entry in
multiple places and like the idea of being able to use it directly as
a brush on the canvas as:

RenderContentOn: html
  html latLongInput on: #position of: self

However WADateInput appears to be significantly more complex than
WADateSelector and I don't entirely understand what is going on. For
example why in WADateInput>>addCallback is a hiddenInput added? I also
guess I'd have to modify WARenderCanvas to add something like:

WARenderCanvas>>latitudeLongitudeInput
   ^ self brush: NALatitudeLongitudeInput new

Any thoughts on the relative merits of the two approaches and why are
there two Date input widgets?

Thanks in advance

Nick