mouse: Offer a separate option for edge scrolling

When a touchpad supports it. When the option is set, it will
automatically disable two-finger scrolling.

The scrolling method used by each individual touchpad is implemented in
mutter, not here.

https://bugzilla.gnome.org/show_bug.cgi?id=761461

configure.ac

@@ -97,7 +97,7 @@ NETWORK_MANAGER_APPLET_REQUIRED_VERSION=1.2.0
 MODEM_MANAGER_REQUIRED_VERSION=0.7
 LIBNOTIFY_REQUIRED_VERSION=0.7.3
 GNOME_DESKTOP_REQUIRED_VERSION=3.21.2
-SCHEMAS_REQUIRED_VERSION=3.19.3
+SCHEMAS_REQUIRED_VERSION=3.21.4
 LIBWACOM_REQUIRED_VERSION=0.7
 CLUTTER_REQUIRED_VERSION=1.11.3
 GOA_REQUIRED_VERSION=3.15.1

panels/mouse/gnome-mouse-properties.c

@@ -76,6 +76,7 @@ static void
 setup_touchpad_options (CcMousePropertiesPrivate *d)
 {
 	gboolean edge_scroll_enabled;
+	gboolean two_finger_scroll_enabled;
 	gboolean have_two_finger_scrolling;
 	gboolean have_edge_scrolling;
 	gboolean have_tap_to_click;
@@ -92,15 +93,37 @@ setup_touchpad_options (CcMousePropertiesPrivate *d)
 
 	gtk_widget_show_all (WID ("touchpad-frame"));
 
-	gtk_widget_set_visible (WID ("edge-scrolling-row"), have_edge_scrolling && !have_two_finger_scrolling);
+	gtk_widget_set_visible (WID ("two-finger-scrolling-row"), have_two_finger_scrolling);
+	gtk_widget_set_visible (WID ("edge-scrolling-row"), have_edge_scrolling);
 	gtk_widget_set_visible (WID ("tap-to-click-row"), have_tap_to_click);
 
 	edge_scroll_enabled = g_settings_get_boolean (d->touchpad_settings, "edge-scrolling-enabled");
+	two_finger_scroll_enabled = g_settings_get_boolean (d->touchpad_settings, "two-finger-scrolling-enabled");
 	d->changing_scroll = TRUE;
 	gtk_switch_set_active (GTK_SWITCH (WID ("edge-scrolling-switch")), edge_scroll_enabled);
+	gtk_switch_set_active (GTK_SWITCH (WID ("two-finger-scrolling-switch")), two_finger_scroll_enabled);
 	d->changing_scroll = FALSE;
 }
 
+static void
+two_finger_scrolling_changed_event (GtkSwitch *button,
+				    gboolean   state,
+				    gpointer user_data)
+{
+	CcMousePropertiesPrivate *d = user_data;
+
+	if (d->changing_scroll)
+		return;
+
+	g_settings_set_boolean (d->touchpad_settings, "two-finger-scrolling-enabled", state);
+	gtk_switch_set_state (button, state);
+
+	if (state && gtk_widget_get_visible (WID ("edge-scrolling-row"))) {
+		/* Disable edge scrolling if two-finger scrolling is enabled */
+		gtk_switch_set_state (GTK_SWITCH (WID ("edge-scrolling-switch")), FALSE);
+	}
+}
+
 static void
 edge_scrolling_changed_event (GtkSwitch *button,
 			      gboolean   state,
@@ -111,8 +134,13 @@ edge_scrolling_changed_event (GtkSwitch *button,
 	if (d->changing_scroll)
 		return;
 
-	g_settings_set_boolean (d->touchpad_settings, "edge-scrolling-switch", state);
+	g_settings_set_boolean (d->touchpad_settings, "edge-scrolling-enabled", state);
 	gtk_switch_set_state (button, state);
+
+	if (state && gtk_widget_get_visible (WID ("two-finger-scrolling-row"))) {
+		/* Disable two-finger scrolling if edge scrolling is enabled */
+		gtk_switch_set_state (GTK_SWITCH (WID ("two-finger-scrolling-switch")), FALSE);
+	}
 }
 
 static gboolean
@@ -254,6 +282,8 @@ setup_dialog (CcMousePropertiesPrivate *d)
 
 	g_signal_connect (WID ("edge-scrolling-switch"), "state-set",
 			  G_CALLBACK (edge_scrolling_changed_event), d);
+	g_signal_connect (WID ("two-finger-scrolling-switch"), "state-set",
+			  G_CALLBACK (two_finger_scrolling_changed_event), d);
 
 	gtk_list_box_set_header_func (GTK_LIST_BOX (WID ("touchpad-options-listbox")), cc_list_box_update_header_func, NULL, NULL);
 }

panels/mouse/gnome-mouse-properties.ui

@@ -615,6 +615,59 @@
                             </child>
                           </object>
                         </child>
+                        <child>
+                          <object class="GtkListBoxRow" id="two-finger-scrolling-row">
+                            <property name="visible">False</property>
+                            <property name="can_focus">True</property>
+                            <property name="no_show_all">True</property>
+                            <property name="activatable">false</property>
+                            <child>
+                              <object class="GtkGrid" id="two-finger-scrolling-grid">
+                                <property name="visible">True</property>
+                                <property name="can_focus">False</property>
+                                <property name="row_spacing">0</property>
+                                <property name="column_spacing">32</property>
+                                <property name="margin_start">12</property>
+                                <property name="margin_end">6</property>
+                                <property name="margin_top">6</property>
+                                <property name="margin_bottom">6</property>
+                                <property name="valign">center</property>
+                                <child>
+                                  <object class="GtkLabel" id="two-finger-scrolling-label">
+                                    <property name="visible">True</property>
+                                    <property name="can_focus">False</property>
+                                    <property name="hexpand">True</property>
+                                    <property name="xalign">0</property>
+                                    <property name="valign">end</property>
+                                    <property name="label" translatable="yes">Two-finger Scrolling</property>
+                                    <property name="use_underline">True</property>
+                                    <property name="mnemonic_widget">two-finger-scrolling-switch</property>
+                                  </object>
+                                  <packing>
+                                    <property name="left_attach">0</property>
+                                    <property name="top_attach">0</property>
+                                    <property name="width">1</property>
+                                    <property name="height">1</property>
+                                  </packing>
+                                </child>
+                                <child>
+                                  <object class="GtkSwitch" id="two-finger-scrolling-switch">
+                                    <property name="visible">True</property>
+                                    <property name="can_focus">True</property>
+                                    <property name="halign">end</property>
+                                    <property name="valign">center</property>
+                                  </object>
+                                  <packing>
+                                    <property name="left_attach">1</property>
+                                    <property name="top_attach">0</property>
+                                    <property name="width">1</property>
+                                    <property name="height">2</property>
+                                  </packing>
+                                </child>
+                              </object>
+                            </child>
+                          </object>
+                        </child>
                         <child>
                           <object class="GtkListBoxRow" id="edge-scrolling-row">
                             <property name="visible">False</property>