From 6480c7039bdf7e8f15f7d1415460db255910c40b Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Nelson=20Ben=C3=ADtez=20Le=C3=B3n?=

 <nbenitezl+gnome@gmail.com>

Date: Sun, 28 May 2017 22:35:05 +0500

Subject: [PATCH] sidebar-thumbnails: fix clunky scrolling

Caused by GtkIconView doing an invalidate and relayout of *all*

items in the view anytime we update model data in any indiviual

item (which happens with all the items that are getting in and out

of the scrolling area while we scroll). This caused GtkIconView to

machine-gunned us with "size-allocate" signals, a signal we were

using to update thumbnails when the sidebar is resized.

Fixed by connecting to the GtkTreeModel "row-changed" signal before

GtkIconView does it, and stop emission from there.

As we don't depend now on "size-allocate" signals to show thumbnails

while we scroll, just queue a draw on the icon view when a

thumbnail finish rendering.

Thanks Jose Aliste for first spotting the problem.

https://bugzilla.gnome.org/show_bug.cgi?id=691448

---

 shell/ev-sidebar-thumbnails.c | 24 ++++++++++++++++++++++++

 1 file changed, 24 insertions(+)

diff --git a/shell/ev-sidebar-thumbnails.c b/shell/ev-sidebar-thumbnails.c

index 253eabf..c22e92e 100644

--- a/shell/ev-sidebar-thumbnails.c

+++ b/shell/ev-sidebar-thumbnails.c

@@ -802,9 +802,26 @@ ev_sidebar_thumbnails_device_scale_factor_changed_cb (EvSidebarThumbnails *sideb

 }

 static void

+ev_sidebar_thumbnails_row_changed (GtkTreeModel *model,

+                                   GtkTreePath  *path,

+                                   GtkTreeIter  *iter,

+                                   gpointer      data)

+{

+	guint signal_id;

+

+	signal_id = GPOINTER_TO_UINT (data);

+

+	/* PREVENT GtkIconView "row-changed" handler to be reached, as it will

+	 * perform a full invalidate and relayout of all items, See bug:

+	 * https://bugzilla.gnome.org/show_bug.cgi?id=691448#c9 */

+	g_signal_stop_emission (model, signal_id, 0);

+}

+

+static void

 ev_sidebar_thumbnails_init (EvSidebarThumbnails *ev_sidebar_thumbnails)

 {

 	EvSidebarThumbnailsPrivate *priv;

+	guint signal_id;

 	priv = ev_sidebar_thumbnails->priv = EV_SIDEBAR_THUMBNAILS_GET_PRIVATE (ev_sidebar_thumbnails);

@@ -814,6 +831,11 @@ ev_sidebar_thumbnails_init (EvSidebarThumbnails *ev_sidebar_thumbnails)

 					       G_TYPE_BOOLEAN,

 					       EV_TYPE_JOB_THUMBNAIL);

+	signal_id = g_signal_lookup ("row-changed", GTK_TYPE_TREE_MODEL);

+	g_signal_connect (GTK_TREE_MODEL (priv->list_store), "row-changed",

+			  G_CALLBACK (ev_sidebar_thumbnails_row_changed),

+			  GUINT_TO_POINTER (signal_id));

+

 	priv->swindow = gtk_scrolled_window_new (NULL, NULL);

 	gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (priv->swindow),

@@ -962,6 +984,8 @@ thumbnail_job_completed_callback (EvJobThumbnail      *job,

 			    COLUMN_JOB, NULL,

 			    -1);

         cairo_surface_destroy (surface);

+

+        gtk_widget_queue_draw (priv->icon_view);

 }

 static void

-- 

2.9.3