Return True/False on set_next_row

app/musicmuster.py

@@ -1031,6 +1031,7 @@ class Window(QMainWindow, Ui_MainWindow):
         # Show closing volume graph
         if track_sequence.current.fade_graph:
             track_sequence.current.fade_graph.GraphWidget = self.widgetFadeVolume
+            track_sequence.current.fade_graph.clear()
             track_sequence.current.fade_graph.plot()
         else:
             log.error("No fade_graph")
@@ -1074,11 +1075,15 @@ class Window(QMainWindow, Ui_MainWindow):
                 self.btnPreview.setChecked(False)
                 return
 
+            try:
                 with db.Session() as session:
                     self.preview_track_manager = PreviewTrackManager(
                         session=session, track_id=track_id, row_number=row_number
                     )
                     self.preview_track_manager.play()
+            except ValueError as e:
+                log.error(f"Error creating PreviewTrackManager({str(e)})")
+                return
 
         else:
             if self.preview_track_manager:

app/playlistmodel.py

@@ -382,8 +382,6 @@ class PlaylistModel(QAbstractTableModel):
         Return text for display
         """
 
-        log.debug(f"display_role({row=}, {column=}")
-
         # Set / reset column span
         if column == HEADER_NOTES_COLUMN:
             column_span = 1
@@ -1229,9 +1227,11 @@ class PlaylistModel(QAbstractTableModel):
 
         return True
 
-    def set_next_row(self, row_number: Optional[int]) -> None:
+    def set_next_row(self, row_number: Optional[int]) -> bool:
         """
         Set row_number as next track. If row_number is None, clear next track.
+
+        Return True if successful else False.
         """
 
         log.debug(f"set_next_row({row_number=})")
@@ -1241,7 +1241,7 @@ class PlaylistModel(QAbstractTableModel):
             if track_sequence.next:
                 track_sequence.next = None
             else:
-                return
+                return True
         else:
             # Get plrid of row
             try:
@@ -1252,14 +1252,14 @@ class PlaylistModel(QAbstractTableModel):
                     f"{self.playlist_id=}"
                     "IndexError"
                 )
-                return
+                return False
             if prd.track_id is None or prd.plr_rownum is None:
                 log.error(
                     f"playlistmodel.set_next_track({row_number=}, "
                     "No track / row number "
                     f"{self.playlist_id=}, {prd.track_id=}, {prd.plr_rownum=}"
                 )
-                return
+                return False
 
             old_next_row: Optional[int] = None
             if track_sequence.next:
@@ -1270,8 +1270,8 @@ class PlaylistModel(QAbstractTableModel):
                     track_sequence.next = MainTrackManager(session, prd.plrid)
                     self.invalidate_row(row_number)
                 except ValueError as e:
-                    log.error(f"Error creating PlaylistTrack({prd=}): ({str(e)})")
+                    log.error(f"Error creating MainTrackManager({prd=}): ({str(e)})")
-                    return
+                    return False
 
             self.signals.search_wikipedia_signal.emit(
                 self.playlist_rows[row_number].title
@@ -1283,6 +1283,8 @@ class PlaylistModel(QAbstractTableModel):
         self.signals.next_track_changed_signal.emit()
         self.update_track_times()
 
+        return True
+
     def setData(
         self,
         index: QModelIndex,
@@ -1688,7 +1690,7 @@ class PlaylistProxyModel(QSortFilterProxyModel):
     def rescan_track(self, row_number: int) -> None:
         return self.source_model.rescan_track(row_number)
 
-    def set_next_row(self, row_number: Optional[int]) -> None:
+    def set_next_row(self, row_number: Optional[int]) -> bool:
         return self.source_model.set_next_row(row_number)
 
     def sort_by_artist(self, row_numbers: List[int]) -> None:

app/trackmanager.py

@@ -381,6 +381,10 @@ class _TrackManager:
         self.row_number = row_number
         self.preview_player = preview_player
 
+        # Check file readable
+        if file_is_unreadable(track.path):
+            raise ValueError(f"_TrackManager.__init__: {track.path=} unreadable")
+
         self.artist = track.artist
         self.bitrate = track.bitrate
         self.duration = track.duration