procedure Tfmain.OpenForm(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 Tfmain.form2menuClick(Sender: TObject); begin OpenForm(Tform2,form2, self); end;
//菜单响应 procedure TFormMain.SetActiveClientForm(AFormClass: TFormClass); var bFoundChild : Boolean; I : integer; begin Screen.Cursor := crAppStart; try
bFoundChild := False; for I := 0 to MDIChildCount-1 do begin if(MDIChildren[I].ClassType = AFormClass) then begin MDIChildren[I].BringToFront; bFoundChild := True; Break; end; end; if(not bFoundChild) then FActiveClinetForm := AFormClass.Create(Self); //AddOrSetActiveFormToMenuMain; end; finally Screen.Cursor := crDefault; application.ProcessMessages; end; end; procedure TFormMain.Action1Excute(.... begin SetActiveClientForm(TForm1); end; procedure TFormMain.Action2Excute(.... begin SetActiveClientForm(TForm1); end;
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 Tfmain.form2menuClick(Sender: TObject);
begin
OpenForm(Tform2,form2, self);
end;
procedure TFormMain.SetActiveClientForm(AFormClass: TFormClass);
var
bFoundChild : Boolean;
I : integer;
begin
Screen.Cursor := crAppStart;
try
bFoundChild := False;
for I := 0 to MDIChildCount-1 do
begin
if(MDIChildren[I].ClassType = AFormClass) then
begin
MDIChildren[I].BringToFront;
bFoundChild := True;
Break;
end;
end;
if(not bFoundChild) then
FActiveClinetForm := AFormClass.Create(Self);
//AddOrSetActiveFormToMenuMain;
end; finally
Screen.Cursor := crDefault;
application.ProcessMessages;
end;
end;
procedure TFormMain.Action1Excute(....
begin
SetActiveClientForm(TForm1);
end;
procedure TFormMain.Action2Excute(....
begin
SetActiveClientForm(TForm1);
end;
子窗体:=nil;即可。