Delphi. How to disable Vcl Themes for TFileOpenDialog and TOpenDialog

Question

How to disable Vcl Themes for TFileOpenDialog and TOpenDialog ?

I try

procedure TForm1.FormCreate(Sender: TObject);
var
  chosenDirectory: String;
  openDialog : TFileOpenDialog;
begin

  TStyleManager.Engine.RegisterStyleHook(TFileOpenDialog, TStyleHook);

  chosenDirectory:='';

  try
    openDialog:=TFileOpenDialog.Create(Self);
    openDialog.Options := [fdoPickFolders];
    // var 2
    // Not works
    //TStyleManager.Engine.RegisterStyleHook(TFileOpenDialog, TStyleHook);

    if openDialog.Execute then
      chosenDirectory:=openDialog.FileName;
  finally
    openDialog.Free;
  end;
end;

but it's not work. I try variation 2. It's not work too.

Answer 1

It does not work because FileOpenDialog is system windows dialog, rather than implemented in VCL, so you'll need add system hook based on class name. Plus you'll need to add hooks to class names of all Windows controls on this dialog.

Try something like this. Note that this will affect all system dialogs.

  TStyleManager.Engine.RegisterSysStyleHook('#32770', TSysStyleHook);
  TStyleManager.Engine.RegisterSysStyleHook('ReBarWindow32', TSysStyleHook);
  TStyleManager.Engine.RegisterSysStyleHook('Static', TSysStyleHook);
  TStyleManager.Engine.RegisterSysStyleHook('Edit', TSysStyleHook);
  TStyleManager.Engine.RegisterSysStyleHook('ScrollBar', TSysStyleHook);
  TStyleManager.Engine.RegisterSysStyleHook('ToolbarWindow32', TSysStyleHook);
  TStyleManager.Engine.RegisterSysStyleHook('ComboBox', TSysStyleHook);