[Lazarus] Teaching Pascal at College

Graeme Geldenhuys mailinglists at geldenhuys.co.uk
Fri Oct 14 12:48:58 CEST 2016

On 2016-10-13 23:13, Erwin van den Bosch via Lazarus wrote:
> The problem is that you should separate your business logic and 
> the GUI. With Delphi like RAD it's very difficult to do that. (but it is 
> possible) Everything is coded in events and connected to database aware 
> GUI controls. (In the case of a database application)

Exactly why I use tiOPF for every application I write - even
non-Database applications. Also exactly why I implemented the MGM
(Model-GUI-Mediator) design pattern for use with VCL, LCL and fpGUI
Toolkit - also included in the tiOPF repository.

All my form units are now VERY empty as all the real functionality lives
in mediators. This also makes unit testing of my code much easier.

> Another problem with the RAD way is that a lot is stored in forms (.lfm 
> files) and it's difficult to see/notice changes to those files. 

And exactly why I designed the fpGUI Visual Forms Designer to generate
actual Object Pascal code in a AfterCreate() method, instead of using
*.lfm or *.dfm files.  I now have one unit in my source code revision
system that shows all changes (no need review two files for form
changes), I can easily do a search & replace for form components and
other code, and I also don't need to fire up a visual form designer if I
just want to make one small tweak to a property.


fpGUI Toolkit - a cross-platform GUI toolkit using Free Pascal

My public PGP key:  http://tinyurl.com/graeme-pgp

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