Delphi part:
I have a class with the event and from that event I need to call a procedure passing the interfaced object to it. It works fine in Delphi but I have problems with declaring it in Pascal Script.
To the background - the IGPGraphics
interface is a part of the Delphi GDI+ library
and without methods is defined like this:
type
IGdiplusBase = interface
['{24A5D3F5-4A9B-42A2-9F60-20825E2740F5}']
IGPGraphics = interface(IGdiPlusBase)
['{57F85BA4-CB01-4466-8441-948D03588F54}']
The following is just a simplified Delphi pseudocode of what I need to do in Pascal Script:
type
TRenderEvent = procedure(Sender: TObject; const GPGraphics: IGPGraphics) of object;
TRenderClass = class(TGraphicControl)
private
FOnRender: TRenderEvent;
public
property OnRender: TRenderEvent read FOnRender write FOnRender;
end;
// when the TRenderClass object instance fires its OnRender event I want to call
// the RenderObject procedure passing the IGPGraphics interfaced object to it; I
// hope I'm doing it right, I'm just a newbie to this stuff - but it works so far
// in Delphi (since I didn't get it to work in Pascal Script)
procedure TForm1.RenderClass1Render(Sender: TObject; const GPGraphics: IGPGraphics);
begin
RenderObject(GPGraphics, 10, 10);
end;
// what I need in Pascal Script is between these two lines; just pass the interface
// object from the event fired by component to the procedure called from inside it
procedure RenderObject(const GPGraphics: IGPGraphics; X, Y);
begin
// and here to work with the interfaced object somehow
end;
Pascal Script compilation part:
My aim is to have the class with event available in Pascal Script and need to pass that interfaced object to that procedure just like above, so the first I've tried to declare for the compilation time this (but I'm not even sure if that's the right way to do so):
// the interface
PS.AddInterface(Cl.FindInterface('IUnknown'), StringToGuid('{57F85BA4-CB01-4466-8441-948D03588F54}'), 'IGPGraphics');
// the type for the event
PS.AddTypeS('TRenderEvent', 'procedure(Sender: TObject; const GPGraphics: IGPGraphics)');
// and the class with the event itself
with PS.AddClassN(PS.FindClass('TGraphicControl'), 'TRenderClass') do
begin
RegisterProperty('OnRender', 'TRenderEvent', iptrw);
end;
Pascal Script runtime part:
Where I'm definitely lost is the runtime part. I can't figure out how to get the interfaced object from the call stack and pass it to my RenderObject procedure:
function RenderClassProc(Caller: TPSExec; Proc: TPSExternalProcRec; Global,
Stack: TPSStack): Boolean;
var
PStart: Cardinal;
begin
PStart := Stack.Count-1;
Result := True;
if Proc.Name = 'RENDEROBJECT' then
begin
// how do I get the interfaced object from Stack (or whatever else) and pass
// it to the RenderObject proc here ? I can't find anything related about it
// except functions that has no parameter index
RenderObject(Stack.Get ?, Stack.GetInt(PStart-2), Stack.GetInt(PStart-3));
end;
end;
And the question is:
Can anyone suggest me how to correctly define compilation and runtime part for this case or correct me with passing the interfaced object somehow ?
P.S. sorry for that Inno-Setup tag but maybe someone from there tried to customize InnoSetup this way.
Thanks a lot!