OnDrawCommandCreate event

rbuser

Hi,

Please see code below, the program crashes when trying to access
aDrawCommand (TObject) passed from RAP in the OnDrawCommandCreate event.
aDrawCommand is always nil. What am I missing.

The following is some Rap passthru stuff I created. I then add a report and
just add a label in the detail section and assign the 2 lines of code in the
RAP section in the designer.

Thanks


//PASS - THRU
type
TmyDrillDownCommandCreate = class(TraSystemFunction)
public
class function Category: string; override;
procedure ExecuteFunction(aParams: TraParamList); override;
class function GetSignature: string; override;
class function HasParams: Boolean; override;
end;

TmyDrillDownCommandAction = class(TraSystemFunction)
public
class function Category: string; override;
procedure ExecuteFunction(aParams: TraParamList); override;
class function GetSignature: string; override;
class function HasParams: Boolean; override;
end;

TmyDrawInfo = class(TComponent)
private
FViewType: string;
FKeyValues: Variant;
public
constructor CreateDrawInfo(aOwner: TComponent; AViewType: string;
AKeyValues: Variant); virtual;
property ViewType: string read FViewType;
property KeyValues: Variant read FKeyValues;
end;

implementation

{ TmyDrillDownCommandCreate }
class function TmyDrillDownCommandCreate.Category: string;
begin
Result := 'My Stuff';
end;

procedure TmyDrillDownCommandCreate.ExecuteFunction(aParams: TraParamList);
var
ADrawCommand: TObject;
lsViewType: string;
lvKeyValue: Variant;
lDrawInfo: TmyDrawInfo;
begin
GetParamValue(0, ADrawCommand);
GetParamValue(1, lsViewType);
GetParamValue(2, lvKeyValue);

lDrawInfo := TmyDrawInfo.CreateDrawInfo(Form1, lsViewType, lvKeyValue);

{attach to draw command}
TComponent(aDrawCommand).Tag := Integer(lDrawInfo);
end;

class function TmyDrillDownCommandCreate.GetSignature: string;
begin
Result := 'procedure DrillDownCommandCreate(aDrawCommand: TObject;
AViewType: string; AKeyValues: Variant);';
end;

class function TmyDrillDownCommandCreate.HasParams: Boolean;
begin
Result := True;
end;

{ TmyDrillDownCommandAction }

class function TmyDrillDownCommandAction.Category: string;
begin
Result := 'My Stuff';
end;

procedure TmyDrillDownCommandAction.ExecuteFunction(aParams: TraParamList);
var
ADrawCommand: TObject;
lsViewType: string;
lvKeyValue: Variant;
lDrawInfo: TmyDrawInfo;
begin
GetParamValue(0, ADrawCommand);

lDrawInfo := TmyDrawInfo(TComponent(aDrawCommand).Tag);
lsViewType := lDrawInfo.ViewType;
lvKeyValue := lDrawInfo.KeyValues;

{attach to draw command}
TComponent(aDrawCommand).Tag := Integer(lDrawInfo);

//do my stuff here
end;

class function TmyDrillDownCommandAction.GetSignature: string;
begin
Result := 'procedure DrillDownCommandAction(const ADrawCommand:
TObject);';
end;

class function TmyDrillDownCommandAction.HasParams: Boolean;
begin
Result := True;
end;

{ TmyDrawInfo }
constructor TmyDrawInfo.CreateDrawInfo(aOwner: TComponent; AViewType:
string; AKeyValues: Variant);
begin
inherited Create(aOwner);
FViewType := AViewType;
FKeyValues := AKeyValues;
end;

//Runtime RAP Code
procedure Label1OnDrawCommandCreate(aDrawCommand: TObject);
begin
DrillDownCommandCreate(aDrawCommand, 'View1', 'FieldValue');
end;

procedure Label1OnDrawCommandClick(aDrawCommand: TObject);
begin
DrillDownCommandAction(ADrawCommand);
end;

nardmoseley

This issue is being researched. For now, as a work around, try using a local
variable to call the pass-thru functions.

Example:

var
lDrawCommand: TObject;
begin
lDrawCommand := aDrawCommand;
DrillDownCommandCreate(lDrawCommand , 'View1', 'FieldValue');
end;



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

rbuser

Thanks for the workaround.