Cara non aktifkan button

bagaimana untuk menonaktifkan button pada delphi misalnya ada 
button save,edit,delete,cancel . Button" tersebut akan aktif bila 
diperlukan...

kalo bisa tolong kasih contoh skrip nya sedikit ...

Thank you..

untuk koding nya sama sperti posting saya sebelumnya .. tolong ya gan ... atau ada skrip salah yg kurang mohon diperbaiki..thx/ atau perlu buat prosedur baru gak????implementation

{$R *.dfm}

procedure TForm1.tampildata;

begin

with dm.blackberry do //dm->data module

begin

sql.Clear;

sql.Add('select * from blackberry');

Active:=false;

Active:=true;

end;

end;

procedure TForm1.bersih;

begin

Edit1.Clear;

Edit2.Clear;

end;

procedure TForm1.BitBtnExitClick(Sender: TObject);

begin

if MessageDlg('Apakah anda yakin menutup form ini?',mtConfirmation,[mbYes,mbNo

],0)=mryes then Form1.Close;

end;

procedure TForm1.FormShow(Sender: TObject);

begin

tampildata;

bersih;

end;

procedure TForm1.BitBtnSaveClick(Sender: TObject);

begin

if Length(Edit1.Text)<>4 then

begin

ShowMessage('Kode Blackberry harus 4 karakter/tidak boleh kosong !!');

Edit1.SetFocus;

exit;

end;

if Length(Edit2.Text)<1 then

begin

ShowMessage('Nama Blackberry Belum Diisi !!');

Edit2.SetFocus;

exit;

end;

if MessageDlg('Data Blackberry ingin disimpan ?',mtInformation,[mbYes,mbNo],0)=mryes then

dm.dbpakarbb.Execute('insert into blackberry values('''+Edit1.Text+''','''

+Edit2.Text+''')');

Dm.blackberry.Requery;

tampildata;

BitBtnSave.Enabled:=True;

Edit1.SetFocus;

end;

procedure TForm1.Edit1Change(Sender: TObject);

begin

dm.blackberry.SQL.Clear;

dm.blackberry.SQL.Add('select * from blackberry where kd_bb='''+Edit1.Text+'''');

dm.blackberry.Open;;

if not dm.blackberry.Eof then

begin

if MessageDlg('Nama Blackberry sudah ada, ingin diedit ?',mtInformation,[mbYes,mbNo],0)=mryes then

begin

Edit2.Text:=dm.blackberry.FieldValues['nm_bb'];

Edit1.Enabled:=false;

BitBtnEdit.Enabled:=true;

BitBtnDelete.Enabled:=true;

BitBtnSave.Enabled:=false;

BitBtnCancel.Enabled:=true;

edit2.SetFocus;

end

else

begin

tampildata;

exit;

end;

end;

end;

procedure TForm1.BitBtnCancelClick(Sender: TObject);

begin

tampildata;

BitBtnSave.Enabled:=True;

Edit1.SetFocus;

end;

procedure TForm1.BitBtnEditClick(Sender: TObject);

begin

if MessageDlg('Yakin untuk diupdate ??',mtInformation,[mbYes,mbno],0)=mryes then

dm.dbpakarbb.Execute('update blackberry set nm_bb='''+Edit2.Text+''' where kd_bb='''

+Edit1.Text+'''');

dm.blackberry.Requery;

ShowMessage('Data sudah diupdate');

tampildata;

BitBtnSave.Enabled:=true;

bersih;

exit;

end;

procedure TForm1.BitBtnDeleteClick(Sender: TObject);

begin

if MessageDlg('Data Blackberry Ingin dihapus ?',mtInformation,[mbYes,mbNo],0)=mrYes then

dm.dbpakarbb.Execute('delete from blackberry where kd_bb='''+Edit1.Text+'''');

dm.blackberry.Requery;

ShowMessage('Data sudah dihapus');

tampildata;

BitBtnSave.Enabled:=True;

bersih;

exit;

end;

procedure TForm1.BitBtnRefreshClick(Sender: TObject);

var n,urutan,jkarakter:integer;

kbaru:string[4];

begin

dm.blackberry.sql.Clear;

dm.blackberry.sql.add('select * from blackberry order by kd_bb');

dm.blackberry.open;

if dm.blackberry.recordcount=0 then

n:=1

else begin

dm.blackberry.last;

urutan:=strtoint(copy(dm.blackberry.fieldvalues['kd_bb'],2,3));

n:=urutan+1;

end;

jkarakter:=length(trim(inttostr(n)));

case jkarakter of

1:kbaru:='B00'+trim(inttostr(n));

2:kbaru:='B0'+trim(inttostr(n));

3:kbaru:='B'+trim(inttostr(n));

end;

edit1.text:=kbaru;

edit1.selstart:=length(kbaru);

edit2.setfocus;

tampildata;

bitbtnsave.enabled:=true;

end;

procedure TForm1.FormCreate(Sender: TObject);

begin

end;

end.