Re: 4Js question

"Five Cats" <cats_spam@[127.0.0.1]> wrote ... > > A customer wants something which work best if there were two windows > working in tandem, one with the 4GL program accessing their database, > and the other which got refreshed with the help for the field they are > currently in, as they move the cursor round the screen. > > Is this possible with 4Js? I had a read of the manual and realised I > hadn't a clue. I think I could pull it off. 4JS have added a concept of Channels into the language a while ago, so I think you could probably invoke another 4GL program that handles the 2nd screen, and drive it from the first by sending messages down the channel. I don't think it would be difficult. The language itself doesn't support this. With Genero, you could probably do it a bit easier using the "Web Services" facility they have added. It's basically a remote procedure call, so that takes care of having to invent your own protocol and messaging. Just call for work and send the data across. The other end can be a slave that displays data to fields etc. To use Genero Web Services (GWS) to it's truest potential, you are supposed to make it accessible via a web browser and the "Genero Application Server" which fields the WS requests and starts up a 4GL Web Services server to handle the request. However the very trivial test program provided with GWS is just a little server that you start up, and it gets one connection from a trivial client (source also provided) and then interacts only with that client. It's this simpler interaction that would be ideal for the job. There is a very healthy set of mailing lists for all the FourJs products. The most active one now is the Genero group, but I'm sure the BDL (aka original 4JS) is still bubbling along nicely. I'm sure you can find your way into the newsgroups by looking around their website at www.4js.com. The techie teams from 4JS read and interact very freely on the mailing lists so it's very useful resource.

"Andrew Hamm" <ahamm@mail.com> wrote ... > > The language itself doesn't support this. What I mean is, 4JS has not added a facility that directly allows you to drive two different screens. You still have the model of one screen at a time. If you used 4JS in GUI mode, you could get away with sending the GUI interaction to one screen that was running the graphical client, and use text-mode DISPLAY commands to display stuff to a text screen. However you won't be able to use DISPLAY AT so the quality of the stuff on the text screen would be severely limited. I sometimes embed DISPLAY "Now calling foobar function" into the code to have crude tracing of errant code - these plain display messages go to the character screen which is typically your telnet/rlogin/ssh connection when you are programming.