[gtk+/gestures: 161/173] colorplane: Fully port to GtkGesture

[Carlos Garnacho <carlosg src gnome org>]

commit 495c74b6d8d0da87f0e0c55e4eb2d5083c4b0091
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed May 14 12:56:16 2014 +0200

    colorplane: Fully port to GtkGesture
    
    A GtkGestureDrag is used for color selection, removing also the
    need to track the pointer state in widget data. The GDK grab performed
    just to set the crosshair cursor has been replaced by a call
    to gdk_window_set_device_cursor(), which will be unset if the
    drag operation is finished, or cancelled due to the implicit grab
    being broken.

 gtk/gtkcolorplane.c |  187 ++++++++++++++++++++++++---------------------------
 1 files changed, 87 insertions(+), 100 deletions(-)
---
diff --git a/gtk/gtkcolorplane.c b/gtk/gtkcolorplane.c
index 26467e9..0b232f7 100644
--- a/gtk/gtkcolorplane.c
+++ b/gtk/gtkcolorplane.c
@@ -19,6 +19,7 @@
 
 #include "gtkcolorplaneprivate.h"
 
+#include "gtkgesturedrag.h"
 #include "gtkgesturelongpress.h"
 #include "gtkaccessible.h"
 #include "gtkadjustment.h"
@@ -32,8 +33,8 @@ struct _GtkColorPlanePrivate
   GtkAdjustment *v_adj;
 
   cairo_surface_t *surface;
-  gboolean in_drag;
 
+  GtkGesture *drag_gesture;
   GtkGesture *long_press_gesture;
 };
 
@@ -180,32 +181,27 @@ plane_configure (GtkWidget         *widget,
 }
 
 static void
-set_cross_grab (GtkWidget *widget,
-                GdkDevice *device,
-                guint32    time)
+set_cross_cursor (GtkWidget *widget,
+                  gboolean   enabled)
 {
-  GdkCursor *cursor;
-
-  cursor = gdk_cursor_new_for_display (gtk_widget_get_display (GTK_WIDGET (widget)),
-                                       GDK_CROSSHAIR);
-  gdk_device_grab (device,
-                   gtk_widget_get_window (widget),
-                   GDK_OWNERSHIP_NONE,
-                   FALSE,
-                   GDK_POINTER_MOTION_MASK
-                    | GDK_POINTER_MOTION_HINT_MASK
-                    | GDK_BUTTON_RELEASE_MASK,
-                   cursor,
-                   time);
-  g_object_unref (cursor);
-}
+  GdkCursor *cursor = NULL;
+  GdkWindow *window;
+  GdkDevice *device;
 
-static gboolean
-plane_grab_broken (GtkWidget          *widget,
-                   GdkEventGrabBroken *event)
-{
-  GTK_COLOR_PLANE (widget)->priv->in_drag = FALSE;
-  return TRUE;
+  window = gtk_widget_get_window (widget);
+  device = gtk_gesture_get_device (GTK_COLOR_PLANE (widget)->priv->drag_gesture);
+
+  if (!window || !device)
+    return;
+
+  if (enabled)
+    cursor = gdk_cursor_new_for_display (gtk_widget_get_display (GTK_WIDGET (widget)),
+                                         GDK_CROSSHAIR);
+
+  gdk_window_set_device_cursor (window, device, cursor);
+
+  if (cursor)
+    g_object_unref (cursor);
 }
 
 static void
@@ -237,64 +233,6 @@ update_color (GtkColorPlane *plane,
   gtk_widget_queue_draw (widget);
 }
 
-static gboolean
-plane_button_press (GtkWidget      *widget,
-                    GdkEventButton *event)
-{
-  GtkColorPlane *plane = GTK_COLOR_PLANE (widget);
-
-  if (event->button == GDK_BUTTON_SECONDARY)
-    {
-      gboolean handled;
-
-      g_signal_emit_by_name (widget, "popup-menu", &handled);
-
-      return TRUE;
-    }
-
-  if (plane->priv->in_drag || event->button != GDK_BUTTON_PRIMARY)
-    return FALSE;
-
-  plane->priv->in_drag = TRUE;
-  set_cross_grab (widget, gdk_event_get_device ((GdkEvent*)event), event->time);
-  update_color (plane, event->x, event->y);
-  gtk_widget_grab_focus (widget);
-
-  return TRUE;
-}
-
-static gboolean
-plane_button_release (GtkWidget      *widget,
-                      GdkEventButton *event)
-{
-  GtkColorPlane *plane = GTK_COLOR_PLANE (widget);
-
-  if (!plane->priv->in_drag || event->button != GDK_BUTTON_PRIMARY)
-    return FALSE;
-
-  plane->priv->in_drag = FALSE;
-
-  update_color (plane, event->x, event->y);
-  gdk_device_ungrab (gdk_event_get_device ((GdkEvent *) event), event->time);
-
-  return TRUE;
-}
-
-static gboolean
-plane_motion_notify (GtkWidget      *widget,
-                     GdkEventMotion *event)
-{
-  GtkColorPlane *plane = GTK_COLOR_PLANE (widget);
-
-  if (!plane->priv->in_drag)
-    return FALSE;
-
-  gdk_event_request_motions (event);
-  update_color (plane, event->x, event->y);
-
-  return TRUE;
-}
-
 static void
 hold_action (GtkGestureLongPress *gesture,
              gdouble              x,
@@ -306,17 +244,6 @@ hold_action (GtkGestureLongPress *gesture,
   g_signal_emit_by_name (plane, "popup-menu", &handled);
 }
 
-static gboolean
-plane_touch (GtkWidget     *widget,
-             GdkEventTouch *event)
-{
-  GtkColorPlane *plane = GTK_COLOR_PLANE (widget);
-
-  update_color (plane, event->x, event->y);
-
-  return TRUE;
-}
-
 static void
 sv_move (GtkColorPlane *plane,
          gdouble        ds,
@@ -404,6 +331,57 @@ plane_key_press (GtkWidget   *widget,
 }
 
 static void
+plane_drag_gesture_begin (GtkGestureDrag *gesture,
+                          gdouble         start_x,
+                          gdouble         start_y,
+                          GtkColorPlane  *plane)
+{
+  guint button;
+
+  button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture));
+
+  if (button == GDK_BUTTON_SECONDARY)
+    {
+      gboolean handled;
+
+      g_signal_emit_by_name (plane, "popup-menu", &handled);
+    }
+
+  if (button != GDK_BUTTON_PRIMARY)
+    {
+      gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_DENIED);
+      return;
+    }
+
+  set_cross_cursor (GTK_WIDGET (plane), TRUE);
+  update_color (plane, start_x, start_y);
+  gtk_widget_grab_focus (GTK_WIDGET (plane));
+  gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_CLAIMED);
+}
+
+static void
+plane_drag_gesture_update (GtkGestureDrag *gesture,
+                           gdouble         offset_x,
+                           gdouble         offset_y,
+                           GtkColorPlane  *plane)
+{
+  gdouble start_x, start_y;
+
+  gtk_gesture_drag_get_start_point (GTK_GESTURE_DRAG (gesture),
+                                    &start_x, &start_y);
+  update_color (plane, start_x + offset_x, start_y + offset_y);
+}
+
+static void
+plane_drag_gesture_end (GtkGestureDrag *gesture,
+                        gdouble         offset_x,
+                        gdouble         offset_y,
+                        GtkColorPlane  *plane)
+{
+  set_cross_cursor (GTK_WIDGET (plane), FALSE);
+}
+
+static void
 gtk_color_plane_init (GtkColorPlane *plane)
 {
   AtkObject *atk_obj;
@@ -424,10 +402,21 @@ gtk_color_plane_init (GtkColorPlane *plane)
       atk_object_set_role (atk_obj, ATK_ROLE_COLOR_CHOOSER);
     }
 
+  plane->priv->drag_gesture = gtk_gesture_drag_new (GTK_WIDGET (plane));
+  g_signal_connect (plane->priv->drag_gesture, "drag-begin",
+                   G_CALLBACK (plane_drag_gesture_begin), plane);
+  g_signal_connect (plane->priv->drag_gesture, "drag-update",
+                   G_CALLBACK (plane_drag_gesture_update), plane);
+  g_signal_connect (plane->priv->drag_gesture, "drag-end",
+                   G_CALLBACK (plane_drag_gesture_end), plane);
+  gtk_gesture_attach (plane->priv->drag_gesture, GTK_PHASE_TARGET);
+  gtk_gesture_single_set_touch_only (GTK_GESTURE_SINGLE (plane->priv->drag_gesture),
+                                     FALSE);
+
   plane->priv->long_press_gesture = gtk_gesture_long_press_new (GTK_WIDGET (plane));
   g_signal_connect (plane->priv->long_press_gesture, "pressed",
                     G_CALLBACK (hold_action), plane);
-  gtk_gesture_attach (plane->priv->long_press_gesture, GTK_PHASE_BUBBLE);
+  gtk_gesture_attach (plane->priv->long_press_gesture, GTK_PHASE_TARGET);
 }
 
 static void
@@ -442,6 +431,9 @@ plane_finalize (GObject *object)
   g_clear_object (&plane->priv->s_adj);
   g_clear_object (&plane->priv->v_adj);
 
+  gtk_gesture_detach (plane->priv->drag_gesture);
+  g_clear_object (&plane->priv->drag_gesture);
+
   gtk_gesture_detach (plane->priv->long_press_gesture);
   g_clear_object (&plane->priv->long_press_gesture);
 
@@ -503,12 +495,7 @@ gtk_color_plane_class_init (GtkColorPlaneClass *class)
 
   widget_class->draw = plane_draw;
   widget_class->configure_event = plane_configure;
-  widget_class->button_press_event = plane_button_press;
-  widget_class->button_release_event = plane_button_release;
-  widget_class->motion_notify_event = plane_motion_notify;
-  widget_class->grab_broken_event = plane_grab_broken;
   widget_class->key_press_event = plane_key_press;
-  widget_class->touch_event = plane_touch;
 
   g_object_class_install_property (object_class,
                                    PROP_H_ADJUSTMENT,