g_signal_connect (priv->page_cache, "page-changed", G_CALLBACK (page_changed_cb), sidebar_thumbnails);
sidebar_thumbnails->priv->start_page = 0;
sidebar_thumbnails->priv->end_page = 0;
g_signal_connect (priv->page_cache, "page-changed", G_CALLBACK (page_changed_cb), sidebar_thumbnails);
sidebar_thumbnails->priv->start_page = 0;
sidebar_thumbnails->priv->end_page = 0;