Creating and deleting objects in Fast Report VCL (Delphi) - delphi

Question

I'm using FastReport 4 to display some dynamically generated data and rearrange it in the report.
I use a "template" object in the report to get the initial position (in my real program I copy font properties, alignment, etc.)
I've managed to create a small project so I can create a memo component in the report, preview the report, and then remove the component so I can reuse the report with different data.
However, when I free the created object, I lose other objects from the report (in this case, my template object is not found the second time I preview the report).
What is the right way to create and remove objects from a Fast Report report?
Here is the pascal unit:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, frxClass;
type
TForm1 = class(TForm)
frxReport1: TfrxReport;
btn1: TButton;
procedure btn1Click(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.btn1Click(Sender: TObject);
var
modelObj: TfrxComponent;
newObj: TfrxMemoView;
begin
modelObj := frxReport1.FindObject('modelObj');
newObj := TfrxMemoView.Create(modelObj.Parent);
newObj.CreateUniqueName;
newObj.Text := 'Whee';
newObj.SetBounds(modelObj.Left, modelObj.Top + modelObj.Height,
modelObj.Width, modelObj.Height);
frxReport1.PrepareReport;
frxReport1.ShowPreparedReport;
newObj.Free;
end;
end.
Here's the DFM:
object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 299
ClientWidth = 635
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
PixelsPerInch = 96
TextHeight = 13
object btn1: TButton
Left = 224
Top = 48
Width = 75
Height = 25
Caption = 'btn1'
TabOrder = 0
OnClick = btn1Click
end
object frxReport1: TfrxReport
Version = '4.15'
DotMatrixReport = False
IniFile = '\Software\Fast Reports'
PreviewOptions.Buttons = [pbPrint, pbLoad, pbSave, pbExport, pbZoom, pbFind, pbOutline, pbPageSetup, pbTools, pbEdit, pbNavigator, pbExportQuick]
PreviewOptions.Zoom = 1.000000000000000000
PrintOptions.Printer = 'Por defecto'
PrintOptions.PrintOnSheet = 0
ReportOptions.CreateDate = 41905.757295162040000000
ReportOptions.LastChange = 41905.757295162040000000
ScriptLanguage = 'PascalScript'
ScriptText.Strings = (
'begin'
''
'end.')
Left = 72
Top = 32
Datasets = <>
Variables = <>
Style = <>
object Data: TfrxDataPage
Height = 1000.000000000000000000
Width = 1000.000000000000000000
end
object Page1: TfrxReportPage
PaperWidth = 216.000000000000000000
PaperHeight = 279.000000000000000000
PaperSize = 1
LeftMargin = 10.000000000000000000
RightMargin = 10.000000000000000000
TopMargin = 10.000000000000000000
BottomMargin = 10.000000000000000000
object PageHeader1: TfrxPageHeader
Height = 279.685220000000000000
Top = 18.897650000000000000
Width = 740.787880000000000000
object modelObj: TfrxMemoView
Left = 166.299320000000000000
Top = 30.236240000000000000
Width = 264.567100000000000000
Height = 18.897650000000000000
ShowHint = False
Color = clYellow
Font.Charset = DEFAULT_CHARSET
Font.Color = clBlack
Font.Height = -13
Font.Name = 'Arial'
Font.Style = []
Memo.UTF8W = (
'Model')
ParentFont = False
end
end
end
end
end

Answer 1

Sorry, for my misleading first answer.
It looks like an internal bug in PrepareReport, the objects seem to be exchanged.
var
modelObj: TfrxComponent;
newObj: TfrxMemoView;
cn:String;
begin
modelObj := frxReport1.FindObject('modelObj');
newObj := TfrxMemoView.Create(modelObj.Parent);
newObj.CreateUniqueName;
cn := newObj.Name; // keep for dirty workaround
newObj.Text := 'Whee';
newObj.SetBounds(modelObj.Left, modelObj.Top + modelObj.Height,
modelObj.Width, modelObj.Height);
Showmessage('New: ' + newObj.Name + ' modelObj: ' + modelObj.Name);
frxReport1.PrepareReport;
Showmessage('New: ' + newObj.Name + ' modelObj: ' + modelObj.Name);
frxReport1.ShowPreparedReport;
newObj := TfrxMemoView(frxReport1.FindObject(cn)); // dirty workaround
newObj.Free;
end;
Output:
New: Memo1 modelObj: modelObj
New: modelObj modelObj: Memo1
The workaround shown here will not be a usable way, so loading reports from a file or placing the TfrxReport component on a datamodule which will be created before printing and destroyed afterwards might be the better workarounds until this bug is fixed.