Information

rbuser

Hi
Im currently making a component it works fine.

What I want to know is how I can class my properties togheter I used :

TppPropertyCategoryManager.PropertyCategories.Add('MyCategory',
'MyProperty');

It works fine but I want to make it a bit further something like TppFont
emulate a record property

My other concern is about RTTI I have a class that need more parameters in
his constructor I used the code from ConstructorToRec in GetPropRec

ie I need MyClass.Create(AOwner : TComponent; ACaption : String);

I tried to do this in GetPropRec

If ppEqual(aPropName, 'Create') Then
Begin
MethodToRec(aPropName, True, aPropRec);

aPropRec.ClassType := THSScript;
aPropRec.Params.AddParam('Class', daClass, THSScript, '', False, False);

aPropRec.Params.AddParam('Result', daClass, nil, '', False, False);

aPropRec.Params.AddParam('Caption', daString, Nil, '', False, False);

aPropRec.IsConstructor := True;
End

and I have this in CallMethod

If ppEqual(aMethodName, 'Create') Then
Begin
RetClass := THSScript.Create(Nil);
aParams.SetParamValue(1, Integer(RetClass));
End

No matter where I put the parameter Caption I can use it in the Report
Designer

nardmoseley

1. In the VCL and ReportBuilder it is quite common to group some properties
into a separate class. Examples are TFont, TppPrinterSetup,
TppEmailSettings, etc. Create a class that descends from TPersistent.
Declare some published properties. Override the Assign method so that it
can/assign copy the properties. For examples, see TFont, or in RB see
TppPrinterSetup, TppEmailSettings, etc.

Example (psuedo code):

TmySettings = class(TPeristent)
public
Assign(Source: TPersistent); override;
published
property Enabled: Boolean;
property Width;
end;


TMyComponent
published
property mySettings: TMySettings read FMySettings write SetMySettings:
end;

Note: in the above, implement SetMySettings to call TmySettings.Assign


2. For an example of adding a parameter to a constructor see
TraTComponentRTTI.GetPropRec and TraTComponentRTTI.GetParams, and
TraTComponentRTTI.CallMethod in ppRTTI.pas



--
Nard Moseley
Digital Metaphors
www.digital-metaphors.com