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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>In an attempt to create some more interesting discussion,
other than talking about the crud IDE issues, I am donating some useful code
for discussion, rather than for help. Feel free to keep/use the code if you
want to. Be mean if you feel the need (but if your personal then watch out ;)
Hopefully this may introduce a discussion where people learn something, or are
able to contribute some interesting ideas/information about the topic (which is
object notification and observation).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>In the attached zip is a sample application showing a basic,
but horrible use of the class in uNotifier.pas. TNotifer is a class I wrote a
long while back which loosely follows an observer pattern for allowing
one-to-many observations between an object, and a bunch of interested object. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The main difference this class has between many observer
patterns is that you do not have to modify existing classes, or sub-class
anything, or instantiate anything in your existing objects. The TNotifier handles
all the bindings, you just need to implement one listening event on each
listening object.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The sample app is a corny app that makes child forms (button
click) update a memo based on changes to the memo on the main form. God help me
if I ever did anything as potentially unthread safe as that in a real app.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Fun fun fun…. (I hope the app compiles. You never know
with these tricky little sample apps)<o:p></o:p></span></font></p>
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