How do i draw lines in RAP code?

rbuser

Hi,

How do i draw lines in RAP code? The delphi procedure below needs translated
to RAP code but it won't compile. It doesn't recognize Page/PrintPosRect? Is
this possible to do? I'm new at using RAP.

Greetings,
Filip Moons

Var
ALine: TppDrawLine;
begin
// Normale horizontale lijn 2
ALine := TppDrawLine.Create(Report);
ALine.Page := Report.Engine.Page;
ALine.LinePosition := lpTop;
ALine.Weight := 0.75;
ALine.Top := Report.Engine.PrintPosRect.Top;
ALine.Left := Report.Engine.PrintPosRect.Left;
ALine.Width := ppTopLine.mmWidth;

nardmoseley

By default, not all of the properties and methods are exposed to RAP. You
can easily extend RAP, see the following article.

--------------------------------------------------
Article: Extending RAP
---------------------------------------------------

There are two very simple and powerful techniques to extend the capabilities
of RAP infinitely. These are summarized below and covered in more detail in
the RAP.hlp online help. Demos and tutorials are installed to
RBuilder\Demos\RAP. The tutorial text is located in RAP.hlp.


1. RAP Pass-Through Functions

These are functions that appear in the Language tab of RAP's Code Toolbox.
These functions are written in Delphi and can be called from RAP. RAP's
pass-through function architecture enable's developers to add new built-in
functions to RAP's code toolbox.

2. Extend RAP's RTTI

RAP's Run-time Type information defines what classes and properties can be
accessed via RAP. By default the published properties of any class that is
registered with Delphi's RegisterClass procedure is recognized by RAP. In
addition many of the public properties and methods of ReportBuilder classes
are exposed.







--
Tech Support mailto:support@digital-metaphors.com
Digital Metaphors http://www.digital-metaphors.com

rbuser

Hi Nard,

This is as far as i got. Below you can find the source i used for extending
the RTTI and registering classes.

The TppDrawLine compiles without errors.

RAP-code
procedure ReportOnEndPage;
Var
ALine: TppDrawLine;
begin
ALine := TppDrawLine.Create(Report);
ALine.Page := ALine.Page;
end;

The TppCustomEngine still doesn't compiles without errors. How do I register
the TppCustomEngine so it can be used in RAP code?

RAP-code
procedure ReportOnEndPage;
Var
ALine: TppDrawLine;
begin
ALine := TppDrawLine.Create(Report);
ALine.Page := Report.Engine.Page; <<<
ALine.LinePosition := lpTop;
ALine.Weight := 0.75;
ALine.Top := Report.Engine.PrintPosRect.Top; <<<
ALine.Left := Report.Engine.PrintPosRect.Left; <<<
ALine.Width := Line1.mmWidth;
end;

Could u please give me some more info how to get this running. Thanks.

Greetings,
Filip Moons

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
ppComm, ppRTTI, ppCache, ppDevice, ppEndUsr, ppRelatv, ppProd, ppClass,
ppReport, StdCtrls;

type
TacTppReportRTTI = class(TraTppReportRTTI);

{@TraTppDrawLineRTTI}
TraTppDrawLineRTTI = class(TraTppDrawCommandRTTI)
public
class function RefClass: TClass; override;
end; {class, TraTppDrawLineRTTI}

{@TraTppCustomEngineRTTI}
TraTppCustomEngineRTTI = class(TraTppCacheableRTTI)
public
class function RefClass: TClass; override;
end; {class, TraTppCustomEngineRTTI}


TForm1 = class(TForm)
ppReport1: TppReport;
Designer: TppDesigner;
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

uses
raIDE,ppDrwCmd;

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
begin
Designer.ShowModal;
end;

class function TraTppDrawLineRTTI.RefClass: TClass;
begin
Result := TppDrawLine;
end; {TraTppDrawLineRTTI}

class function TraTppCustomEngineRTTI.RefClass: TClass;
begin
Result := TppCustomEngine;
end; {TraTppCustomEngineRTTI}

Initialization
raUnregisterRTTI(TraTppReportRTTI);
raRegisterRTTI(TacTppReportRTTI);
raRegisterRTTI(TraTppCustomEngineRTTI);
raRegisterRTTI(TraTppDrawLineRTTI);
Finalization
raUnRegisterRTTI(TraTppCustomEngineRTTI);
raUnRegisterRTTI(TraTppDrawLineRTTI);
raUnregisterRTTI(TacTppReportRTTI);
raRegisterRTTI(TraTppReportRTTI);
end.

nardmoseley

Its going to simpler to code a few RAP pass-thru functions.

However, if you want to extend the RTTI you need to add support for any
public properties that you wish to access (only published properties are
supported by default). Your TacTppReportRTTI class does not add support for
any additional properties/methods, such as Engine.

rbuser

I tried that and it gives me access violations on AReport.Engine.Page. I
really could use some help. How would you implement drawing a line in RAP
code. I would be really gratefull for some sample code.

RAP code:
Procedure ReportOnEndPage;
Var
ALine: TppDrawLine;
begin
ALine := TppDrawLine.Create(Report);
ALine.LinePosition := lpTop;
ALine.Weight := 0.75;
ALine.Top := -1;
ALine.Left := -1;
ALine.Width := Label1.Width;
DrawLineCMD(Report,ALine);
end;

Delphi Code
TacDrawLineCMD = class (TraSystemFunction)
public
class function Category: string; override;
procedure ExecuteFunction(aParams: TraParamList); override;
class function GetSignature: string; override;
end;

class function TacDrawLineCMD.Category: string;
begin
Result := 'Draw Line Command';
end;

class function TacDrawLineCMD.GetSignature: string;
begin
Result := 'function DrawLineCMD(var AReport: TppCustomReport; var ALine:
TppDrawLine): Boolean;';
end;

procedure TacDrawLineCMD.ExecuteFunction(aParams: TraParamList);
var
ALine: TppDrawLine;
AReport: TppCustomReport;
begin
GetParamValue(0,AReport);
GetParamValue(1,ALine);

ALine.Page := AReport.Engine.Page;
if ALine.Top = -1 then
ALine.Top := AReport.Engine.PrintPosRect.Top;
if ALine.Left = -1 then
ALine.Left := AReport.Engine.PrintPosRect.Left;

SetParamValue(2,True);
end;

nardmoseley

1. Try removing the 'var' from the RAP function signature for DrawLineCMD.

2. Modify the Delphi library path to include RBuilder\Source and trace in
the debugger

3. If you still have an issue, create a simple example using DBDemos and
email to support@digital-metaphors.com in zip format.