enhancements for the rktplayer

gui.rkt

@@ -116,7 +116,8 @@
     (define current-track-nr #f)
     
     (define (update-track-nr nr)
-      (unless (eq? playlist #f)
+      (unless (or (eq? playlist #f)
+                  (= (send playlist length) 0))
         (dbg-rktplayer "update-track-nr ~a" nr)
         (let ((id (λ () (send playlist track-id current-track-nr))) ;string->symbol (format "track-~a" (+ current-track-nr 1)))))
               (ct current-track-nr))
@@ -537,7 +538,8 @@
       (update-track-nr #f))
 
     (define/public (play-track idx)
-      (send player play-track idx))
+      (unless (= (send playlist length) 0)
+        (send player play-track idx)))
 
     (define/public (pause)
       (send player pause-unpause))

music-library.rkt

@@ -1,5 +1,7 @@
 #lang racket
 
+(require racket-sound)
+
 (provide music-lib-relevant?
          is-music-dir?
          is-music-file?
@@ -14,7 +16,7 @@
           (not (string-prefix? name ".")))
         (if (eq? type 'file)
             (let* ((fn (string-downcase (format "~a" f)))
-                   (exts (list "flac" "mp3")))
+                   (exts (audio-supported-extensions)))
               (let ((l (filter (λ (e) (string-suffix? fn (string-append "." e))) exts)))
                 (not (null? l))))
             #f))))

player.rkt

@@ -266,6 +266,7 @@
       )
 
     (define/public (play-track i)
+      (unless (= (send pl length) 0)
         (dbg-rktplayer "play-track ~a" i)
         (set! state 'stopped)
         (close-player*)
@@ -277,6 +278,7 @@
         (track-nr-updater track)
         (dbg-rktplayer "track-nr-updater called")
         )
+      )
 
     (define/public (stop)
       (stop-and-clear)

playlist.rkt

@@ -377,6 +377,7 @@
                     (if (< i N)
                         (cons (list (send this track-id i) i) (f (+ i 1) N))
                         '()))))
+        (dbg-rktplayer "Number of rows in playlist: ~a" (send this length))
         (let ((rows (f 0 (send this length))))
           (mktable rows 'tracks formatter))))