Using delegate for WindowProc - Is possible and fun!

[bls]

On 12/28/2011 03:45 PM, Tal wrote:
> Can I do something like this :
> ______________________________________________________________________
> extern (Windows) LRESULT delegate (HWND hWnd, UINT message, WPARAM wParam,
> LPARAM lParam) MyWinProcDelegate;
>
> this() {
> 	MyWinProcDelegate =&Events;
> }
>
> extern (Windows) LRESULT Events (HWND hWnd, UINT message, WPARAM wParam,
> LPARAM lParam) {
> 	MessageBoxA(null , "Success!!!" , null ,0);
> 	return DefWindowProcA(hWnd, message, wParam, lParam);
> }
> ______________________________________________________________________
>
> The Events() doesn't seem to fire... am I missing something ?

Hi Tal.
I have added an other example using array of delegates. I guess I know 
what you want to do... so do not miss the end of the document. Enjoy.

import std.stdio;
import std.functional;


int main(string[] argv)
{
	

	// array of delegates
	extern(Windows)	int delegate( int i)[] dg;
	alias dg callback;

	// function to delegate
	callback ~= toDelegate( &test );  // std.functional
	writeln( callback[0]( 1 ) );

	callback ~= toDelegate( &inc );
	writeln( callback[1] (0) );
	writeln (callback[0]( 1 ) );
	readln();


return 0;
}

extern(Windows) int test(int i) { return 41 +i;}
extern(Windows) int inc(int i) { return ++i;}
------------------------------------------------------------------------------------
// Now an associative array of delegates indexed by (of course) HWND  ;)
extern (Windows)
LRESULT delegate (HWND hWnd, UINT message, WPARAM wParam,LPARAM 
lParam)[HWND] dg;

alias dg MyWinProcDelegate;

bjoern