Delphi Grid Visible Item

Question

HI all,

I am working with Delphi 7. I am facing a problem with Grid.

My Grid having 100 rows, I am appending some more after that. For example, I am selected item is on 1oth. The grid shows 20 items on screen at a time. I scrolled the grid to downward. I reached last one. Here grid's Itemindex= 10; Please note the selected item is not showing on the visible window. When I adds the item, the grid refresh and moving to show 10th item.

I don't want to do this.

My requirement is When Adding new rows, Screen should remain same, as shown last time.

Expecting quick reply.

Thanks and Regards,

VIJESH V.NAIR System Analyst. Delhi, India.

Answer 1

Before adding an item bookmark the current row of your table that correspond to dbgrid. Afer adding an item goto your bookmark a sample for working with TBookmark: (you can replace clientdataset1 with your tableName like table1)

unit MainForm;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, DB, DBClient, ExtCtrls, ActnList, Grids, DBGrids,
  DBCtrls;

type
  TfrmMain = class(TForm)
    DataSource1: TDataSource;
    pnlClient: TPanel;
    pnlBottom: TPanel;
    btnFirst: TButton;
    btnLast: TButton;
    btnNext: TButton;
    btnPrior: TButton;
    DBGrid1: TDBGrid;
    ClientDataSet1: TClientDataSet;
    btnSetRecNo: TButton;
    DBNavigator1: TDBNavigator;
    btnGetBookmark: TButton;
    btnGotoBookmark: TButton;
    procedure FormCreate(Sender: TObject);
    procedure btnNextClick(Sender: TObject);
    procedure btnLastClick(Sender: TObject);
    procedure btnSetRecNoClick(Sender: TObject);
    procedure btnFirstClick(Sender: TObject);
    procedure btnPriorClick(Sender: TObject);
    procedure btnGetBookmarkClick(Sender: TObject);
    procedure btnGotoBookmarkClick(Sender: TObject);
  private
    { Private declarations }
    FBookmark: TBookmark;
  public
    { Public declarations }
  end;

var
  frmMain: TfrmMain;

implementation

{$R *.dfm}

procedure TfrmMain.FormCreate(Sender: TObject);
begin
  ClientDataSet1.LoadFromFile('C:\Employee.cds');
end;

procedure TfrmMain.btnFirstClick(Sender: TObject);
begin
  ClientDataSet1.First;
end;

procedure TfrmMain.btnPriorClick(Sender: TObject);
begin
  ClientDataSet1.Prior;
end;

procedure TfrmMain.btnNextClick(Sender: TObject);
begin
  ClientDataSet1.Next;
end;

procedure TfrmMain.btnLastClick(Sender: TObject);
begin
  ClientDataSet1.Last;
end;

procedure TfrmMain.btnSetRecNoClick(Sender: TObject);
var
  Value: string;
begin
  Value := '1';
  if InputQuery('RecNo', 'Enter Record Number', Value) then
    ClientDataSet1.RecNo := StrToInt(Value);
end;

procedure TfrmMain.btnGetBookmarkClick(Sender: TObject);
begin
  if Assigned(FBookmark) then
    ClientDataSet1.FreeBookmark(FBookmark);

  FBookmark := ClientDataSet1.GetBookmark;
end;

procedure TfrmMain.btnGotoBookmarkClick(Sender: TObject);
begin
  if Assigned(FBookmark) then
    ClientDataSet1.GotoBookmark(FBookmark)
  else
    ShowMessage('No bookmark set!');
end;

end.