mainunit.pas

《Delphi7编程100例》代码,书配资料

unit MainUnit;

interface

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

type
  TMainForm = class(TForm)
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

procedure OpenChildForm(FormClass: TFormClass; var Fm; AOwner:TComponent);

var
  MainForm: TMainForm;

implementation

uses Child1Unit, Child2Unit;

{$R *.DFM}

procedure OpenChildForm(FormClass: TFormClass; var Fm; AOwner:TComponent);
var
  i: integer;
  Child:TForm;
begin
  for i := 0 to Screen.FormCount -1 do
      if Screen.Forms[i].ClassType=FormClass then
      begin
        Child:=Screen.Forms[i];
        if Child.WindowState=wsMinimized then
           ShowWindow(Child.handle,SW_SHOWNORMAL)
        else
           ShowWindow(Child.handle,SW_SHOWNA);
        if (not Child.Visible) then Child.Visible:=True;
        Child.BringToFront;
        Child.Setfocus;
        TForm(Fm):=Child;
        exit;
      end;
  Child:=TForm(FormClass.NewInstance);
  TForm(fm):=Child;
  Child.Create(AOwner);
end;


procedure TMainForm.Button1Click(Sender: TObject);
begin
  OpenChildForm(TChildForm1,ChildForm1, Self);
end;

procedure TMainForm.Button2Click(Sender: TObject);
begin
  OpenChildForm(TChildForm2,ChildForm2, Self);
end;

end.