How to create RTTI a component with event (EventToRec)?

rbuser

How to create RTTI a component with event (EventToRec)?
--
Vadim
?



--- posted by geoForum on http://delphi.newswhat.com

nardmoseley

1. Event prop list

If the event is not published, then override the GetEventList method and add
it to the list. (if its published it will be added automatically).

2. Event Id

For each event, you need to have a unique event id - which is an integer
used to identify the event and route it. ReportBuilder defines constants for
the events that it uses. These are defined in ppTypes and prefixed with a
'ci'.

3. Event prop rec

Override the GetPropRec method and add a call to EventToRec. For an example
in ppVar.pas, the TraTppVariableRTTI.GetPropRec method has the following...
(Note: ciComponentCalc and ciComponentReset are event id constants defined
in ppTypes.)

{events}
if (CompareText(aPropName, 'OnCalc') = 0) then
EventToRec(aPropName, ciComponentCalc, True, aPropRec)

else if (CompareText(aPropName, 'OnReset') = 0) then
EventToRec(aPropName, ciComponentReset, True, aPropRec)

4. Event params

If the event requires parameters, then override the GetParams method. For
example in ppVar.pas, the TraTppVariableRTTI.GetParams method contains the
following


if (CompareText(aMethodName, 'OnCalc') = 0) or (CompareText(aMethodName,
'OnReset') = 0) then
begin
Result := TraParamList.Create;

Result.AddParam('Value', daVariant, nil, '', False, True);
end


5. Fire the event.

To fire a RAP event, requires that the component send an event notification
. For example, in ppVar.pas, the TppVariable.DoOnCalc method contains the
following. Note that the event id ciComponentCalc is used.


lParams := TraTppVariableRTTI.GetParams('OnCalc');
lParams.CreateValuePointer(0, lValue);

SendEventNotify(Self, ciComponentCalc, lParams);

lParams.Free;





--
Nard Moseley
Digital Metaphors Corporation
http://www.digital-metaphors.com

nardmoseley

Those are simple integer constants. If applicable you can use any of the
constants defined in ppTypes.pas. Otherwise defin and use your own custom
id's. Sorry if that was not clear.


--
Nard Moseley
Digital Metaphors Corporation
http://www.digital-metaphors.com

rbuser

> EventToRec(aPropName, ciComponentCalc, True, aPropRec)

ciComponentCalc - ???????

I speak about new (my) events (constants such as ciComponentReset are
unsuitable):


TMyEvent = procedure(Sender: Tobject; MyObj: TMyRTTIObject);

--
Vadim



--- posted by geoForum on http://delphi.newswhat.com

rbuser

Thanks !
--
Vadim



--- posted by geoForum on http://delphi.newswhat.com