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just to set the crosshair cursor has been replaced by a call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.

diff --git a/gtk/gtkcolorplane.c b/gtk/gtkcolorplane.c
index 26467e9b87f614ccd04057576e00958bbc1deb2a..0b232f72f5adde3b453a65931f68cf41c07ded5b 100644 (file)
--- 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,
@@ -403,6 +330,57 @@ plane_key_press (GtkWidget   *widget,
   return TRUE;
 }
 
+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)
 {
@@ -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,