Custom Widgets

Question

Chandrashekar, Alaiah <[email protected]> wrote
<snip!>
Do anyone know about developing custom widgets in Forte. I have a
situation were I need to develop a Ruler widget which is very similar
to the Line widget provided by Forte. I tried subclassing it from the
Line widget and it does not allow me to do that. IM(NS)HO, one of the (few!) real weaknesses of Forte is its barrenness,
in the genealogical sense -- most of its objects, including, apparantly,
all the graphic ones, can't have children. My particular graphic gripe
is the lack of a spin widget, but I sympathise.
In SOME cases you can get the "moral equivalent" of subclassed widgets
by other means. These include (but are not limited to!):
* Subclassing non-graphic objects to get a custom display (e.g. a
subclass of IntegerNullable that displays itself as Roman
numerals). I suspect this approach does not meet your needs.
* Writing non-graphic manager objects to manipulate a bunch of graphic
objects in standard ways to make them "look" kind of like a
custom graphic object. For example, one way to get a ruler might
be to put a panel on your window, and create a non-graphic
object that draws appropriately in that panel, and (using an
event handler which must be manually registered) responds to
events in it.
* Create a window that's just one big ruler, and nest that window in
whatever window you want to display a ruler. This is how I
simulated a spin widget.
When choosing among the last two alternatives, I go for the latter, more
out of habit than anything else. I believe that with a nested window you
get a simpler object; but on the other hand you can't usefully nest a
window in an array field (it simply doesn't function) or a mapped
CompoundField (it'll function just fine, but won't automatically update
the mapped object unless you do something to explicitly tell the nested
window what it's supposed to be updating).
You will find a sample app using nested windows in
${FORTE_ROOT}/INSTALL/EXAMPLES/DISPLAY/NESTWIN.PEX
Tom Wyant The opinions expressed in this document are
[email protected] those of the author, except for the
[email protected] following, which is William Shakespeare's:
"The first thing we do is, we'll kill
all the lawyers."
Henry VI, Part II, Act 4, Scene 2

Answer 1

HI
The buttons used in the Program displayed by your link are mostly images used in the buttons, especially for the toolbar. So may have to get out your drawing board and start creating yorur own images. Also the button used for the inner frame, is something that can be achieved by creating a new look and feel for your application. Check out the Code Examples in you sdk, the MetalWorks example in particular. Go through all the looks and feels provided for that application and try to come up with your own, so that you frame buttons will look fancier.
Also search the net for IFrame. I can't remember the site where it is located but it provides you with Java classes for custom JFrames which a have very powerful and interest appearances.
These should get you on your way. Do remember:
1. Images for toolbar buttons and normal JButton
2. Custom Look and Feel for JFrame buttons
All the best.
ICE