안녕하세요 델파이를 처음 접하는 학생입니다
간단한 계산기 하나 만들어 볼려구 코드 짜고 있는데요
실행은 이상이 없는데 버튼을 누르면 edit1으로 먼져 숫자가 입력이 되어야 하는데요
edit2로 숫자가 입력이 되고 버튼12번을 클릭하면 그때서야 정상적으로 edit1 으로 숫자가 들어 가거든요;;;
이거 어떻게 해결해야 할지 한시간째 헤메고 있습니다.... ㅜㅜ
파일을 압축해서 첨부하겠습니다 문제가 뭔지 조언부탁드립니다...

unit Accumulator;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    Edit3: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button5: TButton;
    Button4: TButton;
    Button6: TButton;
    Button7: TButton;
    Button8: TButton;
    Button9: TButton;
    Button10: TButton;
    Button11: TButton;
    Button12: TButton;
    Button13: TButton;
    Button14: TButton;
    Button15: TButton;
    Button16: TButton;
    Button17: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button5Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure Button6Click(Sender: TObject);
    procedure Button7Click(Sender: TObject);
    procedure Button8Click(Sender: TObject);
    procedure Button9Click(Sender: TObject);
    procedure Button10Click(Sender: TObject);
    procedure Button12Click(Sender: TObject);
    procedure Button13Click(Sender: TObject);
    procedure Button14Click(Sender: TObject);
    procedure Button15Click(Sender: TObject);
    procedure Button16Click(Sender: TObject);
    procedure Button11Click(Sender: TObject);
    procedure Button17Click(Sender: TObject);
    procedure FormActivate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  op : char;
implementation
{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '1'
  else Edit2.text :=Edit2.text + '1';
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '2'
  else Edit2.text :=Edit2.text + '2';
end;

procedure TForm1.Button3Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '3'
  else Edit2.text :=Edit2.text + '3';

end;

procedure TForm1.Button4Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '4'
  else Edit2.text :=Edit2.text + '4';

end;

procedure TForm1.Button5Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '5'
  else Edit2.text :=Edit2.text + '5';
end;

procedure TForm1.Button6Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '6'
  else Edit2.text :=Edit2.text + '6';
end;

procedure TForm1.Button7Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '7'
  else Edit2.text :=Edit2.text + '7';
end;

procedure TForm1.Button8Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '8'
  else Edit2.text :=Edit2.text + '8';
end;

procedure TForm1.Button9Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '9'
  else Edit2.text :=Edit2.text + '9';
end;

procedure TForm1.Button10Click(Sender: TObject);
begin
  if   op = '@' then
       Edit1.text :=Edit1.text + '0'
  else Edit2.text :=Edit2.text + '0';
end;

procedure TForm1.Button12Click(Sender: TObject);
begin
  Edit1.text :='';
  Edit2.text :='';
  Edit3.text :='';
  op:='@';
  edit1.setfocus;
end;

procedure TForm1.Button13Click(Sender: TObject);
begin
  op:='+';
  label5.caption:=op;
  edit2.SetFocus;
end;

procedure TForm1.Button14Click(Sender: TObject);
begin
  op:='-';
  label5.caption:=op;
  edit2.SetFocus;
end;

procedure TForm1.Button15Click(Sender: TObject);
begin
  op:='*';
  label5.caption:=op;
  edit2.SetFocus;
end;

procedure TForm1.Button16Click(Sender: TObject);
begin
  op:='/';
  label5.caption:=op;
  edit2.SetFocus;
end;

procedure TForm1.Button11Click(Sender: TObject);
var ans : real;
begin
  if (edit1.text = '') or (edit2.text = '') then
    begin
     showmessage('자료를 모두 입력하신 후 사용하세요!')
    end
  else
    begin
      case op of
        '+':ans:=strtofloat(edit1.text)+strtofloat(edit2.text);
        '-':ans:=strtofloat(edit1.text)-strtofloat(edit2.text);
        '*':ans:=strtofloat(edit1.text)*strtofloat(edit2.text);
        '/':ans:=strtofloat(edit1.text)/strtofloat(edit2.text);
      end;
      edit3.text := floattostr(ans);
    end;
end;

procedure TForm1.Button17Click(Sender: TObject);
begin
  close;
end;

procedure TForm1.FormActivate(Sender: TObject);
begin
  op:='@';
end;
end.