Delphi MediaPlayer notification on song stopped - delphi

Question

I need to embed a trivial MP3 player in a Delphi7 application.
I will simply scan a directory and play all the files in a random order.
I found two possible solutions: one using the Delphi MediaPlayer, and one using the PlaySound Windows API.
None are working.
The problem seems to be in the missing "stop" notification.
Using PlaySound like this:
playsound(pchar(mp3[r].name), 0, SND_ASYNC or SND_FILENAME);
I could not find a way to (politely) ask Windows to inform me when a song stopped playing.
Using the Delphi MediaPlayer, internet is full of suggestions copy/pasted one from the other, like here:
http://www.swissdelphicenter.ch/en/showcode.php?id=689
http://delphi.cjcsoft.net/viewthread.php?tid=44448
procedure TForm1.FormCreate(Sender: TObject);
begin
MediaPlayer1.Notify := True;
MediaPlayer1.OnNotify := NotifyProc;
end;
procedure TForm1.NotifyProc(Sender: TObject);
begin
with Sender as TMediaPlayer do
begin
case Mode of
mpStopped: {do something here};
end;
//must set to true to enable next-time notification
Notify := True;
end;
end;
{
NOTE that the Notify property resets back to False when a
notify event is triggered, so inorder for you to recieve
further notify events, you have to set it back to True as in the code.
for the MODES available, see the helpfile for MediaPlayer.Mode;
}
My problem is that I do get a NotifyValue == nvSuccessfull when a song is over but ALSO when I start a song, so I cannot rely on it.
Furthermore, I never, ever receive a change in state of the "mode" property, that should become mpStopped according to all the examples I found.
There is a similar question here
How can I repeat a song?
but it does not work because, as said, I receive the nvSuccessfull twice, without a way to distinguish between the start and the stop.
Last but not least, this app should work from XP to Win10, that's why I am developing with Delphi7 on WinXP.
Thank you and sorry for the length of this post, but I really tried many solutions before asking for help.

Answer 1

To detect when to load a new file for playing, you can use the OnNotify event and the EndPos and Position properties of the TMediaPlayer (hereafter called MP)
First setup the MP and select a TimeFormat, for example
MediaPlayer1.Wait := False;
MediaPlayer1.Notify := True;
MediaPlayer1.TimeFormat := tfFrames;
MediaPlayer1.OnNotify := NotifyProc;
When you load a file for playing, set the EndPos property
MediaPlayer1.FileName := OpenDialog1.Files[NextMedia];
MediaPlayer1.Open;
MediaPlayer1.EndPos := MediaPlayer1.Length;
MediaPlayer1.Play;
And the OnNotify() procedure
procedure TForm1.NotifyProc(Sender: TObject);
var
mp: TMediaPlayer;
begin
mp:= Sender as TMediaPlayer;
if not (mp.NotifyValue = TMPNotifyValues.nvSuccessful) then Exit;
if mp.Position >= mp.EndPos then
begin
// Select next file to play
NextMedia := (NextMedia + 1) mod OpenDialog1.Files.Count;
mp.FileName := OpenDialog1.Files[NextMedia];
mp.Open;
mp.EndPos := mp.Length;
mp.Position := 0;
mp.Play;
// Set Notify, important
mp.Notify := True;
end;
end;
Finally a comment to your attempt to use the MP.Mode = mpStopped mode to change to a new song. The mode is changed when the buttons are operated, iow mpStopped when the user presses the Stop button. Changing the song and starting to play it would likely not be what the user expected.