[gtk+/overlay-heuristics: 7/8] Update overlay scrolling when current device changes

[Matthias Clasen <matthiasc src gnome org>]

commit 7359a9daec2cf99826b0d19cd65d195e9fd8249e
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Nov 28 12:52:02 2014 -0500

    Update overlay scrolling when current device changes
    
    Instead of looking for the mere presence of a mouse, we now
    look for what device was most recently used to move the pointer
    around. With this approach, we can now treat trackpoints like
    mice, since their presence wont hurt unless they are used.

 gtk/gtkscrolledwindow.c |   42 ++++++++++++++++++++++++++++++------------
 1 files changed, 30 insertions(+), 12 deletions(-)
---
diff --git a/gtk/gtkscrolledwindow.c b/gtk/gtkscrolledwindow.c
index be74fda..9ee8994 100644
--- a/gtk/gtkscrolledwindow.c
+++ b/gtk/gtkscrolledwindow.c
@@ -3593,6 +3593,7 @@ setup_indicator (GtkScrolledWindow *scrolled_window,
   gdk_window_hide (indicator->window);
   gtk_widget_set_opacity (scrollbar, 0.0);
   indicator->current_pos = 0.0;
+  indicator->target_pos = 0.5;
 }
 
 static void
@@ -3641,19 +3642,20 @@ remove_indicator (GtkScrolledWindow *scrolled_window,
 
   gtk_widget_set_opacity (scrollbar, 1.0);
   indicator->current_pos = 1.0;
+  indicator->target_pos = 0.5;
 }
 
 static gboolean
-device_manager_has_mouse (GdkDeviceManager *dm)
+device_manager_mouse_is_current (GdkDeviceManager *dm)
 {
   GdkDevice *cp;
   GList *slaves, *s;
   GdkDevice *device;
   guint32 mouse_time;
-  guint32 other_time;
+  guint32 touch_time;
 
   mouse_time = 0;
-  other_time = 0;
+  touch_time = 0;
 
   cp = gdk_device_manager_get_client_pointer (dm);
   slaves = gdk_device_list_slave_devices (cp);
@@ -3664,17 +3666,22 @@ device_manager_has_mouse (GdkDeviceManager *dm)
       if (g_object_get_data (G_OBJECT (device), "removed"))
         continue;
 
-      if (strstr (gdk_device_get_name (device), "XTEST"))
-        continue;
-
-      if (gdk_device_get_source (device) == GDK_SOURCE_MOUSE)
-        mouse_time = MAX (mouse_time, gdk_device_get_time (device));
-      else
-        other_time = MAX (other_time, gdk_device_get_time (device));
+      switch (gdk_device_get_source (device))
+        {
+        case GDK_SOURCE_MOUSE:
+          mouse_time = MAX (mouse_time, gdk_device_get_motion_time (device));
+          break;
+        case GDK_SOURCE_TOUCHPAD:
+        case GDK_SOURCE_TOUCHSCREEN:
+          touch_time = MAX (touch_time, gdk_device_get_motion_time (device));
+          break;
+        default:
+          break;
+        }
     }
   g_list_free (slaves);
 
-  return mouse_time > other_time;
+  return mouse_time > touch_time;
 }
 
 static void
@@ -3697,7 +3704,7 @@ gtk_scrolled_window_update_touch_mode (GtkScrolledWindow *scrolled_window)
     {
       GdkDeviceManager *dm;
       dm = gdk_display_get_device_manager (gtk_widget_get_display (GTK_WIDGET (scrolled_window)));
-      touch_mode = !device_manager_has_mouse (dm);
+      touch_mode = !device_manager_mouse_is_current (dm);
     }
 
   if (priv->touch_mode != touch_mode)
@@ -3740,6 +3747,14 @@ gtk_scrolled_window_device_removed (GdkDeviceManager  *dm,
 }
 
 static void
+gtk_scrolled_window_device_changed (GdkDeviceManager  *dm,
+                                    GParamSpec        *pspec,
+                                    GtkScrolledWindow *scrolled_window)
+{
+  gtk_scrolled_window_update_touch_mode (scrolled_window);
+}
+
+static void
 gtk_scrolled_window_realize (GtkWidget *widget)
 {
   GtkScrolledWindow *scrolled_window = GTK_SCROLLED_WINDOW (widget);
@@ -3758,6 +3773,8 @@ gtk_scrolled_window_realize (GtkWidget *widget)
                     G_CALLBACK (gtk_scrolled_window_device_added), scrolled_window);
   g_signal_connect (dm, "device-removed",
                     G_CALLBACK (gtk_scrolled_window_device_removed), scrolled_window);
+  g_signal_connect (dm, "notify::current-device",
+                    G_CALLBACK (gtk_scrolled_window_device_changed), scrolled_window);
 }
 
 static void
@@ -3770,6 +3787,7 @@ gtk_scrolled_window_unrealize (GtkWidget *widget)
   dm = gdk_display_get_device_manager (gtk_widget_get_display (widget));
   g_signal_handlers_disconnect_by_func (dm, gtk_scrolled_window_device_added, scrolled_window);
   g_signal_handlers_disconnect_by_func (dm, gtk_scrolled_window_device_removed, scrolled_window);
+  g_signal_handlers_disconnect_by_func (dm, gtk_scrolled_window_device_changed, scrolled_window);
 
   gtk_widget_set_parent_window (priv->hscrollbar, NULL);
   gtk_widget_unregister_window (widget, priv->hindicator.window);