Solved

event handling of dynamic controls

Posted on 2004-04-05
11
208 Views
Last Modified: 2010-04-05
i have created 12 stringgrids now i want to trap there events such as click and double click how should i do ? please help ?
0
Comment
Question by:chotrani_mukesh
  • 5
  • 2
11 Comments
 
LVL 12

Accepted Solution

by:
esoftbg earned 49 total points
ID: 10756654
unit Unit_Q_20943709;

interface

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

type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    procedure FormCreate(Sender: TObject);
    private { Private declarations }
    public  { Public declarations }
    published
      procedure Grid1_Click(Sender: TObject);
      function  Get_Method_By_Name(Method_Name: string): TNotifyEvent;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

function TForm1.Get_Method_By_Name(Method_Name: string): TNotifyEvent;
begin
  @Result := MethodAddress(Method_Name);
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  FOnClick1:     TNotifyEvent;
begin
  FOnClick1 := nil;
  try
  FOnClick1 := Get_Method_By_Name('Grid1_Click');
  finally
    StringGrid1.OnClick := FOnClick1;
  end;
end;

procedure TForm1.Grid1_Click(Sender: TObject);
begin
  ShowMessage('StringGrid1 is just Clicked');
end;

end.
0
 
LVL 12

Expert Comment

by:esoftbg
ID: 10756707
it is a better example (with runtime created StringGrid1) :

unit Unit_Q_20943709;

interface

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

type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
    private { Private declarations }
    public  { Public declarations }
    published
      procedure Grid1_Click(Sender: TObject);
      function  Get_Method_By_Name(Method_Name: string): TNotifyEvent;
  end;

var
  Form1: TForm1;
  StringGrid1: TStringGrid;

implementation

{$R *.dfm}

function TForm1.Get_Method_By_Name(Method_Name: string): TNotifyEvent;
begin
  @Result := MethodAddress(Method_Name);
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  FOnClick1:     TNotifyEvent;
begin
  StringGrid1 := TStringGrid.Create(Self);
  StringGrid1.Parent := Self;
  StringGrid1.Left := 16;
  StringGrid1.Top := 16;
  FOnClick1 := nil;
  try
  FOnClick1 := Get_Method_By_Name('Grid1_Click');
  finally
    StringGrid1.OnClick := FOnClick1;
  end;
end;

procedure TForm1.Grid1_Click(Sender: TObject);
begin
  ShowMessage('StringGrid1 is just Clicked');
end;

end.
0
 
LVL 12

Assisted Solution

by:andrewjb
andrewjb earned 48 total points
ID: 10758120
Errr.. What'yer doin? Just use

StringGrid1.OnClick := Grid1_Click;

That's all..!
0
Optimizing Cloud Backup for Low Bandwidth

With cloud storage prices going down a growing number of SMBs start to use it for backup storage. Unfortunately, business data volume rarely fits the average Internet speed. This article provides an overview of main Internet speed challenges and reveals backup best practices.

 
LVL 12

Expert Comment

by:esoftbg
ID: 10758686
unit Unit_Q_20943709;

interface

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

type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    private { Private declarations }
    public  { Public declarations }
    published
      procedure Grid1_Click(Sender: TObject);
      procedure Grid2_Click(Sender: TObject);
  end;

var
  Form1: TForm1;
  StringGrid1: TStringGrid;
  StringGrid2: TStringGrid;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  StringGrid1 := TStringGrid.Create(Self);
  StringGrid1.Parent := Self;
  StringGrid1.Height := 144;
  StringGrid1.Width := 352;
  StringGrid1.Left := 16;
  StringGrid1.Top := 16;
  @StringGrid1.OnClick := MethodAddress('Grid1_Click');

  StringGrid2 := TStringGrid.Create(Self);
  StringGrid2.Parent := Self;
  StringGrid2.Height := 144;
  StringGrid2.Width := 352;
  StringGrid2.Left := 16;
  StringGrid2.Top := 16;
  @StringGrid2.OnClick := MethodAddress('Grid2_Click');
end;

procedure TForm1.Grid1_Click(Sender: TObject);
begin
  ShowMessage('StringGrid1 is just Clicked');
end;

procedure TForm1.Grid2_Click(Sender: TObject);
begin
  ShowMessage('StringGrid2 was just Clicked');
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  StringGrid1.Destroy;
  StringGrid2.Destroy;
end;

end.
0
 
LVL 12

Expert Comment

by:esoftbg
ID: 10758701
 StringGrid2.Top := 160;
0
 
LVL 12

Expert Comment

by:andrewjb
ID: 10758782
esoftbg,

Your StringGrid1 and 2 variable should really be part of the TForm1 class.

And I still don't understand why you're doing this MethodAddress() business... is there some reason?
0
 
LVL 27

Assisted Solution

by:kretzschmar
kretzschmar earned 48 total points
ID: 10758898
just listening . . .

for assigning events:

with TSomeClass.Create(AOwner) do
begin
   SomeProperty := somevalue;
   SomeEvent := PredefinedEventMethod;
   Name := SomeIdentifier;
end;

procedure PredefinedEventMethod(sender : TObject, ...maybeMorePrams...) ;
begin
  if (Sender is TSomeClass) then
    if TSomeClass(Sender).Name = SomeIdentifier then
      DoThisForThisInstance;
   .... to be continued ...
end;

just as abstract sample

meikl ;-)
0
 
LVL 12

Expert Comment

by:esoftbg
ID: 10758920
Hi andrewjb, I hope this time all is o.k.

unit Unit_Q_20943709;

interface

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

type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    private { Private declarations }
    public  { Public declarations }
      StringGrid1: TStringGrid;
      StringGrid2: TStringGrid;
    published
      procedure Grid1_Click(Sender: TObject);
      procedure Grid2_Click(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  StringGrid1 := TStringGrid.Create(Self);
  StringGrid1.Parent := Self;
  StringGrid1.Height := 144;
  StringGrid1.Width := 352;
  StringGrid1.Left := 16;
  StringGrid1.Top := 16;
  StringGrid1.OnClick := Grid1_Click;

  StringGrid2 := TStringGrid.Create(Self);
  StringGrid2.Parent := Self;
  StringGrid2.Height := 144;
  StringGrid2.Width := 352;
  StringGrid2.Left := 16;
  StringGrid2.Top := 160;
  StringGrid2.OnClick := Grid2_Click;
end;

procedure TForm1.Grid1_Click(Sender: TObject);
begin
  ShowMessage('StringGrid1 is just Clicked');
end;

procedure TForm1.Grid2_Click(Sender: TObject);
begin
  ShowMessage('StringGrid2 was just Clicked');
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  StringGrid1.Destroy;
  StringGrid2.Destroy;
end;

end.
0

Featured Post

Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

This article explains how to create forms/units independent of other forms/units object names in a delphi project. Have you ever created a form for user input in a Delphi project and then had the need to have that same form in a other Delphi proj…
Have you ever had your Delphi form/application just hanging while waiting for data to load? This is the article to read if you want to learn some things about adding threads for data loading in the background. First, I'll setup a general applica…
This Micro Tutorial will give you a basic overview how to record your screen with Microsoft Expression Encoder. This program is still free and open for the public to download. This will be demonstrated using Microsoft Expression Encoder 4.
Two types of users will appreciate AOMEI Backupper Pro: 1 - Those with PCIe drives (and haven't found cloning software that works on them). 2 - Those who want a fast clone of their boot drive (no re-boots needed) and it can clone your drive wh…

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question