{
670: Messaging Between Two Dialogs/Update Backgroung
   Pascal   All       TI-09/30/94


it demonstrates how to broadcast messages to background windows and update
information without changing the selected dialog.

  PRODUCT  :  Pascal                                 NUMBER  :  670
  VERSION  :  All
       OS  :  DOS
     DATE  :  September 30, 1994                       PAGE  :  1/1

    TITLE  :  Messaging Between Two Dialogs/Update Backgroung

{
   This program will create two modeless dialog boxes and will
   allow only one dialog to be created at any time.


   Additionally, it demonstrates how to broadcast messages to
   background windows and update information without changing
   the selected dialog.

}
{$X+}

Program DialogCommunication;

uses Objects, Drivers, Views, Menus, Dialogs, App, Crt;
const
  cmDialog1 = 100;
  cmDialog2 = 101;
  cmDialog1Button = 200;
  cmDialog2Button = 201;

type

 PHelloApp = ^THelloApp;
  THelloApp = object(TApplication)
    procedure MakeDialog;
    procedure HandleEvent(var Event: TEvent); virtual;

    procedure InitMenuBar; virtual;
    procedure InitStatusLine; virtual;
  end;

  PMyDialog1 = ^TMyDialog1;
  TMyDialog1 = object(TDialog)
    procedure MakeDialog2;
    procedure HandleEvent(var Event:TEvent); virtual;
  end;

  PMyDialog2 = ^TMyDialog2;
  TMyDialog2 = object(TMyDialog1)
    procedure HandleEvent(var Event:TEvent); virtual;
  end;

procedure TMyDialog1.HandleEvent(var Event: TEvent);
var
  AreYouThere: PView;
begin
  TDialog.HandleEvent(Event);

  if Event.What = evCommand then
    begin
      case Event.Command of
         cmDialog1Button:
           begin
             AreYouThere:= Message(DeskTop, evBroadcast,
cmDialog2, nil);
             if AreYouThere = nil then
                MakeDialog2
              else
                ClearEvent(Event);
           end
      else
        Exit;
      end;
        ClearEvent(Event);
    end;
end;

procedure TMyDialog1.MakeDialog2;
var
  Dialog2: PMyDialog2;

  R: TRect;
  Button: PButton;
begin
  R.Assign(1,1,40,20);
  Dialog2:= New(PMyDialog2, init(R,'Dialog2'));
  R.Assign(10,10,20,12);
  Button:= New(PButton,Init(R,'Beep', cmDialog2Button,
bfdefault));
  Dialog2^.Insert(Button);
  DeskTop^.Insert(Dialog2);
end;

procedure TMyDialog2.HandleEvent(var Event: TEvent);
begin
  case Event.Command of
    cmDialog2: begin
                 sound(2000); delay(10); nosound;
                 Title:=newstr('Hello world');

                 ReDraw;
                 ClearEvent(Event);
               end;
  end;
  TDialog.HandleEvent(Event);
  if Event.What = evCommand then
    begin
      case Event.Command of
         cmDialog2Button: begin
                            Sound(1000); delay(100); NoSound;
                          end;
      else
        Exit;
      end;
        ClearEvent(Event);
    end;
end;

{ THelloApp }

procedure THelloApp.MakeDialog;
var
  R:TRect;

  Button1: PButton;
  Dialog1: PMyDialog1;
begin
  R.Assign(25, 5, 65, 16);
  Dialog1:= New(PMyDialog1, init(R,'Dialog1'));
  R.Assign(16, 8, 38, 10);
  Button1:= New(PButton, Init(R,'Call Dialog2', cmDialog1Button,
bfDefault));
  Dialog1^.Insert(Button1);
  DeskTop^.Insert(Dialog1);
end;

procedure THelloApp.HandleEvent(var Event: TEvent);
begin
  TApplication.HandleEvent(Event);
  if Event.What = evCommand then
    begin
      case Event.Command of
         cmDialog1:begin

                     MakeDialog;
                   end;
      else
        Exit;
      end;
        ClearEvent(Event);
     end;
end;

procedure THelloApp.InitMenuBar;
var
  R: TRect;
begin
  GetExtent(R);
  R.B.Y := R.A.Y + 1;
  MenuBar := New(PMenuBar, Init(R, NewMenu(
    NewSubMenu('~O~pen Dialogs', hcNoContext, NewMenu(
      NewItem('~D~ialog1','', 0, cmDialog1, hcNoContext,
      NewLine(
      NewItem('E~x~it', 'Alt-X', kbAltX, cmQuit,
        hcNoContext, nil)))), nil))));

end;

procedure THelloApp.InitStatusLine;
var
  R: TRect;
begin
  GetExtent(R);
  R.A.Y := R.B.Y-1;
  StatusLine := New(PStatusLine, Init(R,
    NewStatusDef(0, $FFFF,
      NewStatusKey('', kbF10, cmMenu,
      NewStatusKey('~Alt-X~ Exit', kbAltX, cmQuit, nil)), nil)));
end;

var
  HelloWorld: THelloApp;

begin
  HelloWorld.Init;
  HelloWorld.Run;
  HelloWorld.Done;
end.


DISCLAIMER: You have the right to use this technical information
subject to the terms of the No-Nonsense License Statement that

you received with the Borland product to which this information
pertains.
PACHXA296:PACHXA296