Question:
I have a string grid that is read only. I am trapping any
keystrokes sent to the string grid. I have a button that has a
caption of E&xit. When ever the user presses the x key (even if
the alt key is not pressed) in the string grid, the button
click is executed. How can I prevent this?
Answer:
The following example demonstrates trapping the CM_DIALOGCHAR
message at the form level. This will give you an opportunity to
respond to a dialog character only if the alt key is held down,
preventing the default handeling of the character shortcuts.
Example:
type
TForm1 = class(TForm)
Button1: TButton;
StringGrid1: TStringGrid;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure StringGrid1KeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
private
{ Private declarations }
procedure CMDialogChar(var Message: TCMDialogChar);
message CM_DIALOGCHAR;
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
procedure TForm1.FormCreate(Sender: TObject);
begin
Button1.Caption := 'E&xit';
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
Application.Terminate;
end;
procedure TForm1.StringGrid1KeyDown(Sender: TObject;
var Key: Word; Shift: TShiftState);
begin
ShowMessage('Grid keypress = ' + Char(Key));
Key := 0;
end;
procedure TForm1.CMDialogChar(var Message: TCMDialogChar);
begin
if ssAlt in KeyDataToShiftState(Message.KeyData) then
inherited;
end;