Lazy loading of the album art when the row is visible

This improves the performance for huge album lists.
Using an empty pixbuf to avoid re-tries loading the album art.

diff --git a/src/album_art_panel.py b/src/album_art_panel.py
index 42287ca..63b3150 100644 (file)
--- a/src/album_art_panel.py
+++ b/src/album_art_panel.py
@@ -1,32 +1,36 @@
 #!/usr/bin/env python2.5
 import hildon
 import gtk, gobject
+import os
 from album_art_spec import getCoverArtThumbFileName
 from download_dialog import MussorgskyAlbumArtDownloadDialog
 from utils import escape_html
 from aa_selection_dialog import AlbumArtSelectionDialog, RESPONSE_CLICK
 
+import time
+
+EMPTY_PIXBUF = gtk.gdk.Pixbuf (gtk.gdk.COLORSPACE_RGB, False, 8, 64, 64)
+
 class MussorgskyAlbumArtPanel (hildon.StackableWindow):
 
     def __init__ (self, album_artists):
         hildon.StackableWindow.__init__ (self)
         self.set_title ("Album art handling")
         self.set_border_width (12)
+        print "Create view       :",time.time ()
         self.__create_view ()
+        print "Create view (DONE):", time.time ()
         self.downloader = None
-        # Visible string, image, artist, album
-        self.model = gtk.ListStore (str, gtk.gdk.Pixbuf, str, str)
-
+        # Visible string, image, artist, album, painted!
+        self.model = gtk.ListStore (str, gtk.gdk.Pixbuf, str, str, bool)
+        print "Populate model      :", time.time ()
         for p in album_artists:
             if (not p[0]):
                 continue
-            album_art_path = getCoverArtThumbFileName (p[0])
-            try:
-                pixbuf = gtk.gdk.pixbuf_new_from_file_at_size (album_art_path, 64, 64)
-            except gobject.GError:
-                pixbuf = None
-            t = ("<b>%s</b>\n<small>%s</small>" % (escape_html(p[0]), escape_html(p[1])), pixbuf, p[1], p[0])
+            t = ("".join (["<b>", escape_html (p[0]),"</b>\n<small>",
+                           escape_html(p[1]), "</small>"]), None, p[1], p[0], False)
             self.model.append (t)
+        print "Populate model (DONE):", time.time ()
             
         self.treeview.set_model (self.model)
 
@@ -38,7 +42,13 @@ class MussorgskyAlbumArtPanel (hildon.StackableWindow):
         artist_column.set_expand (True)
         self.treeview.append_column (artist_column)
 
-        album_art = gtk.TreeViewColumn ("Album art", gtk.CellRendererPixbuf (), pixbuf=1)
+        renderer = gtk.CellRendererPixbuf ()
+        album_art = gtk.TreeViewColumn ("Album art", renderer, pixbuf=1)
+        # This doesn't have real effect:
+        album_art.set_sizing (gtk.TREE_VIEW_COLUMN_FIXED)
+        album_art.set_fixed_width (64)
+        
+        album_art.set_cell_data_func (renderer, self.album_art_cell_data_cb)
         self.treeview.append_column (album_art)
 
         pannable_area = hildon.PannableArea ()
@@ -55,6 +65,22 @@ class MussorgskyAlbumArtPanel (hildon.StackableWindow):
         menu.show_all ()
         self.set_app_menu (menu)
 
+    def album_art_cell_data_cb (self, column, cell, model, iter):
+        pixbuf, album, not_first_time = model.get (iter, 1, 3, 4)
+        if (not_first_time):
+            if (pixbuf == None):
+                #print "Calling album art cell data cb", model.get (iter, 3)
+                album_art_path = getCoverArtThumbFileName (album)
+                if (os.path.exists (album_art_path)):
+                    pxb = gtk.gdk.pixbuf_new_from_file_at_size (album_art_path, 64, 64)
+                    model.set (iter, 1, pxb)
+                else:
+                    #print "Cannot find thumbnail in '%s'" % (album_art_path)
+                    model.set (iter, 1, EMPTY_PIXBUF) 
+                    
+        else:
+            model.set (iter, 4, True)
+
     def get_all_album_art (self, user_data):
         dialog = MussorgskyAlbumArtDownloadDialog (self)
         dialog.show_all ()
@@ -75,13 +101,21 @@ class MussorgskyAlbumArtPanel (hildon.StackableWindow):
                 pixbuf = gtk.gdk.pixbuf_new_from_file_at_size (thumb, 64, 64)
                 treeview.get_model ().set (it, 1, pixbuf)
             else:
-                treeview.get_model ().set (it, 1, None)
+                treeview.get_model ().set (it, 1, EMPTY_PIXBUF)
         dialog.destroy ()
+
             
 if __name__ == "__main__":
+    import random
+    
+    artists_albums = [("Artist %d the greatest bolero singer in the universe" % i, "Album <%d>" % i) for i in range (0, 10000)]
 
-    artists_albums = [("Artist %d the greatest bolero singer in the universe" % i, "Album <%d>" % i) for i in range (0, 100)]
+    # Overwrite the get thumb path for testing
+    def local_file (path):
+        return "../thumb%d.124.jpeg" % (random.randint (0, 3))
 
+    global getCoverArtThumbFileName
+    getCoverArtThumbFileName = local_file
 
     window = MussorgskyAlbumArtPanel (artists_albums)
     window.connect ("destroy", gtk.main_quit )