Mega Code Archive
How to use my own Inplace Editors in Grids
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Title: How to use my own Inplace-Editors in Grids
Question: String-Grids are very usefull, but sometimes it's necessary to use an own Inplace-Editor. For example to make a Grid which will allow only numbers but no Text-Characters.
Answer:
When you are using Grids (TStringGrid, TDBGrid), you can input some text in the cells of the grid. This will be done with the "Inplace-Editor" from Borland.
Sometimes it's necessary to make an own Inplace-Editor, for example to prevent the user to give in Text instead of number. The following example shows how to do this.
First you need two new classes: one for your Grid and one for your Inplace-Editor. In this example I use TStringGrid, but it should also work with TDBStringGrid.
unit u_TMyStringGrid;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
Grids;
type
// My own Inplace-Editor. This Editor -for example- only
// allow numbers, no text
TMyInplaceEdit = class (TInplaceEdit)
protected
procedure KeyPress(var Key: Char); override;
end;
// My own StringGrid, which will use my own Inplace-Editor
TMyStringGrid = class(TStringGrid)
protected
function CreateEditor: TInplaceEdit; override;
end;
implementation
{ TMyStringGrid }
// Here i define, that my StringGrid should use MyInplace-Editor
function TMyStringGrid.CreateEditor: TInplaceEdit;
begin
Result := TMyInplaceEdit.Create(Self);
end;
{ TMyInplaceEdit }
//The Inplace-Edit only allowes numers, no text-Characters
procedure TMyInplaceEdit.KeyPress(var Key: Char);
begin
if not (Key in ['0'..'9'])
then begin
beep;
Key := #0
end
else inherited;
end;
end.
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