barcode reader as input... - Programmers Heaven

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Categories

barcode reader as input...

im using a barcode reader as input...

the problem is...
i like to disable the keyboard input...

hope for your kind answers...

best regards,
marc

Comments

  • dj_sanniedj_sannie Posts: 92Member
    : im using a barcode reader as input...
    :
    : the problem is...
    : i like to disable the keyboard input...
    :
    : hope for your kind answers...
    :
    : best regards,
    : marc
    :
    i do not see you're problem, what do u want to disable the key input for a TEdit ?
    if u want to disable key input in a basic delphi componenet than u can use the OnKeyDown event like this.
    [code]procedure TForm1.Edit1KeyDown(Sender: TObject; var Key: Word;
    Shift: TShiftState);
    begin
    Key := 0;
    end;[/code]

    i hope this helps u,

    greets SRK
  • turtleshellturtleshell Posts: 3Member
    : i do not see you're problem, what do u want to disable the key input for a TEdit ?
    : if u want to disable key input in a basic delphi componenet than u can use the OnKeyDown event like this.
    : [code]procedure TForm1.Edit1KeyDown(Sender: TObject; var Key: Word;
    : Shift: TShiftState);
    : begin
    : Key := 0;
    : end;[/code]
    :
    : i hope this helps u,
    :
    : greets SRK
    :

    if you use that code then you could not get the input from the barcode reader... Edit1.Text will have an empty string;

    is there another way?

    thanks for your reply....

    best regards,
    marc


  • zibadianzibadian Posts: 6,349Member
    : : i do not see you're problem, what do u want to disable the key input for a TEdit ?
    : : if u want to disable key input in a basic delphi componenet than u can use the OnKeyDown event like this.
    : : [code]procedure TForm1.Edit1KeyDown(Sender: TObject; var Key: Word;
    : : Shift: TShiftState);
    : : begin
    : : Key := 0;
    : : end;[/code]
    : :
    : : i hope this helps u,
    : :
    : : greets SRK
    : :
    :
    : if you use that code then you could not get the input from the barcode reader... Edit1.Text will have an empty string;
    :
    : is there another way?
    :
    : thanks for your reply....
    :
    : best regards,
    : marc
    :
    :
    :
    You can set the ReadOnly property to true. This way the edit functions more or less as a TLabel.
  • MasterijnMasterijn Posts: 188Member
    [b][red]This message was edited by Masterijn at 2004-5-1 2:4:12[/red][/b][hr]
    : im using a barcode reader as input...
    :
    : the problem is...
    : i like to disable the keyboard input...
    :
    : hope for your kind answers...
    :
    : best regards,
    : marc
    :
    You can set the TForm.KeyPreview = True. In this way you don't need an extra focussed control. But the keydown/keyup handling is form global this way. This is a template you could use, the VK_PAUSE is the preamble (i think its called that way):
    [code]
    procedure TfrmMain.FormKeyDown(Sender: TObject; var Key: Word;
    Shift: TShiftState);
    begin
    if Assigned(FBarcodeReader) then
    begin
    Key := 0;
    end
    else if (Key = VK_PAUSE) then
    FBarcodeReader := TReadBarcode.Create;
    end;


    procedure TfrmMain.FormKeyPress(Sender: TObject; var Key: Char);
    begin
    if Assigned(FBarcodeReader) then
    begin
    if (Key <> #13) then
    FBarcodeReader.PushChar(Key);
    Key := #0;
    end;
    end;

    procedure TfrmMain.FormKeyUp(Sender: TObject; var Key: Word;
    Shift: TShiftState);
    begin
    if Assigned(FBarcodeReader) then
    begin
    if Key = VK_RETURN then
    begin
    try
    Key := 0;
    with FBarcodeReader do
    begin
    Process;
    end;
    finally
    FreeAndNil(FBarcodeReader);
    end;
    end
    end;
    end;
    [/code]






  • turtleshellturtleshell Posts: 3Member
    You can set the TForm.KeyPreview = True. In this way you don't need an extra focussed control. But the keydown/keyup handling is form global this way. This is a template you could use, the VK_PAUSE is the preamble (i think its called that way):
    : [code]
    : procedure TfrmMain.FormKeyDown(Sender: TObject; var Key: Word;
    : Shift: TShiftState);
    : begin
    : if Assigned(FBarcodeReader) then
    : begin
    : Key := 0;
    : end
    : else if (Key = VK_PAUSE) then
    : FBarcodeReader := TReadBarcode.Create;
    : end;
    :
    :
    : procedure TfrmMain.FormKeyPress(Sender: TObject; var Key: Char);
    : begin
    : if Assigned(FBarcodeReader) then
    : begin
    : if (Key <> #13) then
    : FBarcodeReader.PushChar(Key);
    : Key := #0;
    : end;
    : end;
    :
    : procedure TfrmMain.FormKeyUp(Sender: TObject; var Key: Word;
    : Shift: TShiftState);
    : begin
    : if Assigned(FBarcodeReader) then
    : begin
    : if Key = VK_RETURN then
    : begin
    : try
    : Key := 0;
    : with FBarcodeReader do
    : begin
    : Process;
    : end;
    : finally
    : FreeAndNil(FBarcodeReader);
    : end;
    : end
    : end;
    : end;
    : [/code]
    :


    thanks for the reply... but i dont have TReadBarcode and i dont know how to make TReadBarcode...
    hoping for your reply...
    thanks and best regards,
    marc



Sign In or Register to comment.