[gtk+] gtkgesture: Filter out touchpad events by default.

[Carlos Garnacho <carlosg src gnome org>]

commit 97e67e21a1e21215f1191a5be1f2fb102fb2d6a0
Author: Carlos Garnacho <carlosg gnome org>
Date:   Thu Jul 9 19:04:59 2015 +0200

    gtkgesture: Filter out touchpad events by default.
    
    The gestures that don't want touchpad gesture events are majority,
    even those that want such events will only listen to subsets (eg.
    pinch, swipe,...).
    
    So it makes sense to ignore touchpad events by default, and let
    subclasses opt those in.

 gtk/gtkgesture.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkgesture.c b/gtk/gtkgesture.c
index 827d66d..e6eefaf 100644
--- a/gtk/gtkgesture.c
+++ b/gtk/gtkgesture.c
@@ -158,6 +158,9 @@ static guint signals[N_SIGNALS] = { 0 };
 
 #define BUTTONS_MASK (GDK_BUTTON1_MASK | GDK_BUTTON2_MASK | GDK_BUTTON3_MASK)
 
+#define EVENT_IS_TOUCHPAD_GESTURE(e) ((e)->type == GDK_TOUCHPAD_SWIPE || \
+                                      (e)->type == GDK_TOUCHPAD_PINCH)
+
 GList * _gtk_gesture_get_group_link (GtkGesture *gesture);
 
 G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GtkGesture, gtk_gesture, GTK_TYPE_EVENT_CONTROLLER)
@@ -562,6 +565,18 @@ gesture_within_window (GtkGesture *gesture,
 }
 
 static gboolean
+gtk_gesture_filter_event (GtkEventController *controller,
+                          const GdkEvent     *event)
+{
+  /* Even though GtkGesture handles these events, we want
+   * touchpad gestures disabled by default, it will be
+   * subclasses which punch the holes in for the events
+   * they can possibly handle.
+   */
+  return EVENT_IS_TOUCHPAD_GESTURE (event);
+}
+
+static gboolean
 gtk_gesture_handle_event (GtkEventController *controller,
                           const GdkEvent     *event)
 {
@@ -681,6 +696,7 @@ gtk_gesture_class_init (GtkGestureClass *klass)
   object_class->set_property = gtk_gesture_set_property;
   object_class->finalize = gtk_gesture_finalize;
 
+  controller_class->filter_event = gtk_gesture_filter_event;
   controller_class->handle_event = gtk_gesture_handle_event;
   controller_class->reset = gtk_gesture_reset;