StButton: fix hover and grab tracking

Use StWidget:track-hover rather than doing it ourselves. Don't assume
that hover is always TRUE after an enter_event or FALSE after a
leave_event, since we have a pointer grab and will be getting other
actors' events.

Don't ungrab the pointer when it leaves the button, since that
destroys the whole point of getting a grab in the first place.

Only consider the button to have been clicked when it has both grab
(meaning the mouse was pressed over the button) and hover (meaning the
mouse was released over the button).

Also remove the virtual pressed/released methods, which weren't being
used anyway.

https://bugzilla.gnome.org/show_bug.cgi?id=633853

src/st/st-button.c

@@ -72,9 +72,9 @@ struct _StButtonPrivate
   gchar            *text;
 
   guint             is_pressed : 1;
-  guint             is_hover : 1;
   guint             is_checked : 1;
   guint             is_toggle : 1;
+  guint             has_grab : 1;
 
   gint              spacing;
 };
@@ -123,15 +123,32 @@ st_button_style_changed (StWidget *widget)
 }
 
 static void
-st_button_real_pressed (StButton *button)
+st_button_press (StButton *button)
 {
+  if (button->priv->is_pressed)
+    return;
+
+  button->priv->is_pressed = TRUE;
   st_widget_add_style_pseudo_class (ST_WIDGET (button), "active");
 }
 
 static void
-st_button_real_released (StButton *button)
+st_button_release (StButton *button,
+                   gboolean  clicked)
 {
+  if (!button->priv->is_pressed)
+    return;
+
+  button->priv->is_pressed = FALSE;
   st_widget_remove_style_pseudo_class (ST_WIDGET (button), "active");
+
+  if (clicked)
+    {
+      if (button->priv->is_toggle)
+        st_button_set_checked (button, !button->priv->is_checked);
+
+      g_signal_emit (button, button_signals[CLICKED], 0);
+    }
 }
 
 static gboolean
@@ -143,14 +160,10 @@ st_button_button_press (ClutterActor       *actor,
   if (event->button == 1)
     {
       StButton *button = ST_BUTTON (actor);
-      StButtonClass *klass = ST_BUTTON_GET_CLASS (button);
-
-      button->priv->is_pressed = TRUE;
 
       clutter_grab_pointer (actor);
-
+      button->priv->has_grab = TRUE;
-      if (klass->pressed)
+      st_button_press (button);
-        klass->pressed (button);
 
       return TRUE;
     }
@@ -165,25 +178,17 @@ st_button_button_release (ClutterActor       *actor,
   if (event->button == 1)
     {
       StButton *button = ST_BUTTON (actor);
-      StButtonClass *klass = ST_BUTTON_GET_CLASS (button);
+      gboolean is_click;
 
-      if (!button->priv->is_pressed)
+      is_click = button->priv->has_grab && st_widget_get_hover (ST_WIDGET (button));
-        return FALSE;
+      st_button_release (button, is_click);
 
-      clutter_ungrab_pointer ();
+      if (button->priv->has_grab)
-
-      if (button->priv->is_toggle)
         {
-          st_button_set_checked (button, !button->priv->is_checked);
+          button->priv->has_grab = FALSE;
+          clutter_ungrab_pointer ();
         }
 
-      button->priv->is_pressed = FALSE;
-
-      if (klass->released)
-        klass->released (button);
-
-      g_signal_emit (button, button_signals[CLICKED], 0);
-
       return TRUE;
     }
 
@@ -195,12 +200,19 @@ st_button_enter (ClutterActor         *actor,
                  ClutterCrossingEvent *event)
 {
   StButton *button = ST_BUTTON (actor);
+  gboolean ret;
 
-  st_widget_add_style_pseudo_class (ST_WIDGET (button), "hover");
+  ret = CLUTTER_ACTOR_CLASS (st_button_parent_class)->enter_event (actor, event);
 
-  button->priv->is_hover = TRUE;
+  if (button->priv->has_grab)
+    {
+      if (st_widget_get_hover (ST_WIDGET (button)))
+        st_button_press (button);
+      else
+        st_button_release (button, FALSE);
+    }
 
-  return CLUTTER_ACTOR_CLASS (st_button_parent_class)->enter_event (actor, event);
+  return ret;
 }
 
 static gboolean
@@ -208,24 +220,19 @@ st_button_leave (ClutterActor         *actor,
                  ClutterCrossingEvent *event)
 {
   StButton *button = ST_BUTTON (actor);
+  gboolean ret;
 
-  button->priv->is_hover = FALSE;
+  ret = CLUTTER_ACTOR_CLASS (st_button_parent_class)->leave_event (actor, event);
 
-  if (button->priv->is_pressed)
+  if (button->priv->has_grab)
     {
-      StButtonClass *klass = ST_BUTTON_GET_CLASS (button);
+      if (st_widget_get_hover (ST_WIDGET (button)))
-
+        st_button_press (button);
-      clutter_ungrab_pointer ();
+      else
-
+        st_button_release (button, FALSE);
-      button->priv->is_pressed = FALSE;
-
-      if (klass->released)
-        klass->released (button);
     }
 
-  st_widget_remove_style_pseudo_class (ST_WIDGET (button), "hover");
+  return ret;
-
-  return CLUTTER_ACTOR_CLASS (st_button_parent_class)->leave_event (actor, event);
 }
 
 static void
@@ -302,9 +309,6 @@ st_button_class_init (StButtonClass *klass)
 
   g_type_class_add_private (klass, sizeof (StButtonPrivate));
 
-  klass->pressed = st_button_real_pressed;
-  klass->released = st_button_real_released;
-
   gobject_class->set_property = st_button_set_property;
   gobject_class->get_property = st_button_get_property;
   gobject_class->finalize = st_button_finalize;
@@ -361,6 +365,7 @@ st_button_init (StButton *button)
   button->priv->spacing = 6;
 
   clutter_actor_set_reactive (CLUTTER_ACTOR (button), TRUE);
+  st_widget_set_track_hover (ST_WIDGET (button), TRUE);
 }
 
 /**

src/st/st-button.h

@@ -66,8 +66,6 @@ struct _StButtonClass
   StBinClass parent_class;
 
   /* vfuncs, not signals */
-  void (* pressed)    (StButton     *button);
-  void (* released)   (StButton     *button);
   void (* transition) (StButton     *button);
 
   /* signals */