Creating Dynamic Screens

Why did I call this tip ‘Creating Dynamic Screens’?  Well first of all I thought it sounded pretty cool.  But secondly, I run into situations where I want to make screens that may look different during the course of the day depending on some criteria that is constantly changing.  Or to put it another way, dynamic.  The problem is that TouchPro pages are all predrawn, or static images.    So if you draw it one way, it will always look that way.  If you want it to look different, you have to draw a different page.  Sure there are some exceptions, such as autozones, which draw menu item buttons dynamically, but what if that isn’t what you want to do?
The Secret Window Transparency Feature

Before I introduce you to a demonstration, let me explain the trick to making this work.  Long ago, TouchPro’s windows were given the ability to be transparent.  This feature turned out to be a little ahead of its time, as the typical workstation of a few years ago simply took too long to draw multiple windows.  But now it’s time has come.

To make a section of a window transparent, it must have an attribute of black on black and use the space character.  This last point is a little harder than it sounds, because everything looks like a space when you have black on black.  It’s kind of like a black cat at midnight.  You can’t see it but its still there and you’ll trip over it if you don’t watch out.  Here’s a little trick to tell if your black on black section is all spaces.  Select Edit Copy (Ctl-C) and highlight the transparent area.  Since screenpainter uses it’s own attribute for the highlight area, any black cats (err, non-space characters) will become visible.
And Now the Example

[img:3gqtcnns]http://www.possupport.net/dealer/kbase/images/seat1.gif[/img:3gqtcnns]

I have made a simple little application that acts as a seating chart.  It displays available tables in green and occupied tables in red.  Pressing the table toggles the status.  You can see that this could never have been done by making a separate page for each table, as it would have taken 213 or (let’s see, 2x2x2x…. carry the 1,…, hmmm…) 8,192 pages.  Using the trick mentioned above, I did it using only 15 windows.  The bottom window contained the original screen image, with all the tables set to green.  Then I made one window for each table.  These were each totally transparent except for a red table button.  The last window was completely transparent, but contained all the touch zones.  A bucket file is used to keep track of the status for each seat.  I won’t explain any more details in this tech tip, but you can download SeatDemo if you want to take a closer look.

[img:3gqtcnns]http://www.possupport.net/dealer/kbase/images/seat2.gif[/img:3gqtcnns]