Implementation of signals and slots in Delphi?

Question

Is there an implementation for Delphi of a signal and slot mechanism for event dispatching?

Answer 1

Search for multicast events. There are several implementations, for example,

• http://www.deltics.co.nz/blog/?p=137
• http://blogs.embarcadero.com/abauer/2008/09/03/38867
• http://www.codebot.org/delphi/?doc=9568

Some of them need generics, therefore only D> 2009.

Answer 2

Despite the fact that you yourself can implement multi-sheeted events, they are not supported directly in the language, unlike C # and VB.NET. The lack of language support makes any attempt to emulate multiple events quite awkward.

It is interesting that in C ++ there is no support for signals and slots, and the Qt solution is associated with an additional process in the chain of compilation tools - the compiler of meta objects.

Answer 3

I spent some time ago on how the Allen Bauer Multicast event code works. It has some limitations, but works well in my code. You can see the code here .

Of course it only works in Delphi> 2009