unit Unit1;    interface    uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ComCtrls;    type
  TForm1 = class(TForm)
    StatusBar1: TStatusBar;
  private
    { Private declarations }
  public
    { Public declarations }
  end;    var
  Form1: TForm1;    implementation    uses Unit2;    {$R *.dfm}    end.
unit Unit2;    interface    uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;    type
  TForm2 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;    var
  Form2: TForm2;    implementation    uses Unit1;
{$R *.dfm}    procedure TForm2.Button1Click(Sender: TObject);
begin
  form1.StatusBar1.Panels[0].Text:='try';
end;    end.
*.dpr文件：
program Project1;    uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1},
  Unit2 in 'Unit2.pas' {Form2};    {$R *.res}    begin
  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.CreateForm(TForm2, Form2);
  Application.Run;
end.
其中属性设置如下： 
  form1.FormStyle:=fsMDIForm;
  Form2.FormStyle:=fsMDIChild;
  Form1.StatusBar1.SimplePanel:=false;