Question

I am using Delphi 7 under Windows 7 to download files.

I want to change the cursor during the download.

I set the Screen.Cursor := crHourGlass; , but , after looking at the constant cursor numbers in Controls.pas, I was wondering whether there are other numbers I can use to change the cursor into ( I don’t want to add a cursor to my resource file, I just want to use standard numbers which I can use without having to add resources ).

Answer 1

does other numbers produce meaning
full cursors

No. Other numbers besides built-in cursors constants will produce a default cursor which is identical to TCursor(crDefault) (in other terms – HCURSOR(Screen.Cursors[crDefault])). These built-in cursors resides in the application resources and preloaded on VCL startup. To add custom cursor you HAVE to add CURSOR resource and then load it and add it to VCL.

procedure TForm1.FormCreate(Sender: TObject); platform;
const
  crCustom = 42;
var
  Cursor: HCURSOR;
begin
  Cursor := LoadCursor(HInstance, 'CUSTOM');
  Win32Check(Cursor <> 0);  // required error check
  Screen.Cursors[crCustom] := Cursor;
  { Done, newly added crCustom is ready to use }

  Self.Cursor := crCustom; // for example - lets show custom cursor

  { also, TScreen object will manage resource handle }
  { and perform cleanup for you, so DestroyCursor call is unnecessary }
end;

More complicated example with indirect cursor construction NB: example have numerous flaws: 1) DestroyIcon call is erroneous 2) they’d noticed it if there was error checking after all API calls