Drag and drop

I am trying to implement drag and drop between DBGrids on two seperate forms but as yet I haven't managed it. Can someone help me?
alanwardAsked:
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d003303Commented:
do the two forms belong to the same process (i.e. the same application instance) ? If not, you will have to implement OLE drag and drop to transfer data between process boundaries.

Slash/d003303
0
ZifNabCommented:
Here is an example :

Push Fill grid button; (bitbutton1)
Push Show other form button (button1)

Push mouse button on grid and drag to other form

Regards, Zif.

program Project1;

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1},
  Unit2 in 'Unit2.pas' {Form2};

{$R *.RES}

begin
  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.CreateForm(TForm2, Form2);
  Application.Run;
end.

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, Buttons, Grids;

type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    BitBtn1: TBitBtn;
    Button1: TButton;
    procedure BitBtn1Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

uses Unit2;

{$R *.DFM}

procedure TForm1.BitBtn1Click(Sender: TObject);
begin
 Form2.Show;
end;

procedure TForm1.Button1Click(Sender: TObject);

var i,j : integer;
begin
 for i := 1 to 10 do
  for j := 1 to 10 do
   StringGrid1.Cells[i,j] := 'Cell '+IntToStr(i)+IntToStr(j);
end;

end.

unit Unit2;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Grids;

type
  TForm2 = class(TForm)
    StringGrid1: TStringGrid;
    procedure StringGrid1DragOver(Sender, Source: TObject; X, Y: Integer;
      State: TDragState; var Accept: Boolean);
    procedure StringGrid1DragDrop(Sender, Source: TObject; X, Y: Integer);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form2: TForm2;

implementation

uses Unit1;

{$R *.DFM}

procedure TForm2.StringGrid1DragOver(Sender, Source: TObject; X,
  Y: Integer; State: TDragState; var Accept: Boolean);
begin
  if Source is TStringGrid then
    Accept := True;end;

procedure TForm2.StringGrid1DragDrop(Sender, Source: TObject; X,
  Y: Integer);
begin
  if Source is TStringGrid then
   begin    StringGrid1.Cells[Form1.StringGrid1.Col,Form1.StringGrid1.Row] :=      Form1.StringGrid1.Cells[Form1.StringGrid1.Col,Form1.StringGrid1.Row];   end;
end;

end.

Questions? Just ask.

0
alanwardAuthor Commented:
ZifNab's answer involved String grids my question was specifically about DBGrids, I don't know if the same code will work for both.
0
ZifNabCommented:
sure it works with dbgrids! Only the dragdrop is different :
With this example you can see that the dbgrid in form2 will accept from dbgrid1.

program Project1;

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1},
  Unit2 in 'Unit2.pas' {Form2};

{$R *.RES}

begin
  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.CreateForm(TForm2, Form2);
  Application.Run;
end.

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Grids, DBGrids, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    DBGrid1: TDBGrid;
    procedure Button1Click(Sender: TObject);
    procedure FormActivate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

uses Unit2;

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
begin
 Form2.Show;
end;

procedure TForm1.FormActivate(Sender: TObject);
begin
 dbgrid1.dragmode :=  dmAutomatic;
end;

end.

unit Unit2;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Grids, DBGrids;

type
  TForm2 = class(TForm)
    DBGrid1: TDBGrid;
    procedure DBGrid1DragOver(Sender, Source: TObject; X, Y: Integer;
      State: TDragState; var Accept: Boolean);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form2: TForm2;

implementation

{$R *.DFM}

procedure TForm2.DBGrid1DragOver(Sender, Source: TObject; X, Y: Integer;
  State: TDragState; var Accept: Boolean);
begin
if Source is TDBGrid then
            Accept := True;
end;


end.

0

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