[gnome-shell] Import ShellButtonBox as StClickable

[Colin Walters <walters src gnome org>]

commit 93f3412f70fb3cd00c7df04975d5b3ae875a8bb3
Author: Colin Walters <walters verbum org>
Date:   Mon Nov 16 13:28:51 2009 -0500

    Import ShellButtonBox as StClickable
    
    Now a StBin, and add hover/active style properties.  Also, add the
    event to the CLICKED signal.  Otherwise a straightforward namespace
    transformation.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=602131

 src/Makefile-st.am    |    2 +
 src/st/st-clickable.c |  330 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/st/st-clickable.h |   35 +++++
 3 files changed, 367 insertions(+), 0 deletions(-)
---
diff --git a/src/Makefile-st.am b/src/Makefile-st.am
index 618e334..a6a85f1 100644
--- a/src/Makefile-st.am
+++ b/src/Makefile-st.am
@@ -72,6 +72,7 @@ st_source_h =					\
     st/st-box-layout.h				\
     st/st-box-layout-child.h			\
     st/st-button.h				\
+    st/st-clickable.h           \
     st/st-clipboard.h				\
     st/st-drawing-area.h        \
     st/st-entry.h				\
@@ -109,6 +110,7 @@ st_source_c =					\
     st/st-box-layout.c				\
     st/st-box-layout-child.c			\
     st/st-button.c				\
+    st/st-clickable.c           \
     st/st-clipboard.c				\
     st/st-drawing-area.c        \
     st/st-entry.c				\
diff --git a/src/st/st-clickable.c b/src/st/st-clickable.c
new file mode 100644
index 0000000..bc5ad49
--- /dev/null
+++ b/src/st/st-clickable.c
@@ -0,0 +1,330 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+
+/**
+ * SECTION:st-clickable
+ * @short_description: A bin with methods and properties useful for implementing buttons
+ *
+ * A #StBin subclass which translates lower-level Clutter button events
+ * into higher level properties which are useful for implementing "button-like"
+ * actors.
+ */
+
+#include "st-clickable.h"
+
+G_DEFINE_TYPE (StClickable, st_clickable, ST_TYPE_BIN);
+
+struct _StClickablePrivate {
+  gboolean active;
+  gboolean held;
+  gboolean hover;
+  gboolean pressed;
+
+  guint initiating_button;
+};
+
+/* Signals */
+enum
+{
+  CLICKED,
+  LAST_SIGNAL
+};
+
+enum {
+  PROP_0,
+
+  PROP_ACTIVE,
+  PROP_HOVER,
+  PROP_PRESSED,
+};
+
+static guint st_clickable_signals [LAST_SIGNAL] = { 0 };
+
+static void
+sync_pseudo_class (StClickable *self)
+{
+  st_widget_set_style_pseudo_class (ST_WIDGET (self),
+                                    (self->priv->pressed || self->priv->active) ? "pressed" :
+                                      (self->priv->hover ? "hover" : NULL));
+}
+
+static void
+set_active (StClickable  *self,
+            gboolean      active)
+{
+  if (self->priv->active == active)
+    return;
+  self->priv->active = active;
+  sync_pseudo_class (self);
+  g_object_notify (G_OBJECT (self), "active");
+}
+
+static void
+set_hover (StClickable  *self,
+           gboolean      hover)
+{
+  if (self->priv->hover == hover)
+    return;
+  self->priv->hover = hover;
+  sync_pseudo_class (self);
+  g_object_notify (G_OBJECT (self), "hover");
+}
+
+static void
+set_pressed (StClickable  *self,
+             gboolean      pressed)
+{
+  if (self->priv->pressed == pressed)
+    return;
+  self->priv->pressed = pressed;
+  sync_pseudo_class (self);
+  g_object_notify (G_OBJECT (self), "pressed");
+}
+
+static gboolean
+st_clickable_contains (StClickable     *self,
+                       ClutterActor    *actor)
+{
+  while (actor != NULL && actor != (ClutterActor*)self)
+    {
+      actor = clutter_actor_get_parent (actor);
+    }
+  return actor != NULL;
+}
+
+static gboolean
+st_clickable_enter_event (ClutterActor         *actor,
+                          ClutterCrossingEvent *event)
+{
+  StClickable *self = ST_CLICKABLE (actor);
+
+  if (st_clickable_contains (self, event->related))
+    return TRUE;
+  if (!st_clickable_contains (self, event->source))
+    return TRUE;
+
+  g_object_freeze_notify (G_OBJECT (actor));
+
+  if (self->priv->held)
+    set_pressed (self, TRUE);
+  set_hover (self, TRUE);
+
+  g_object_thaw_notify (G_OBJECT (actor));
+
+  return TRUE;
+}
+
+static gboolean
+st_clickable_leave_event (ClutterActor         *actor,
+                              ClutterCrossingEvent *event)
+{
+  StClickable *self = ST_CLICKABLE (actor);
+
+  if (st_clickable_contains (self, event->related))
+    return TRUE;
+
+  set_hover (self, FALSE);
+  set_pressed (self, FALSE);
+
+  return TRUE;
+}
+
+static gboolean
+st_clickable_button_press_event (ClutterActor       *actor,
+                                 ClutterButtonEvent *event)
+{
+  StClickable *self = ST_CLICKABLE (actor);
+
+  if (event->click_count != 1)
+    return FALSE;
+
+  if (self->priv->held)
+    return TRUE;
+
+  if (!st_clickable_contains (self, event->source))
+    return FALSE;
+
+  self->priv->held = TRUE;
+  self->priv->initiating_button = event->button;
+  clutter_grab_pointer (CLUTTER_ACTOR (self));
+
+  set_pressed (self, TRUE);
+
+  return TRUE;
+}
+
+static gboolean
+st_clickable_button_release_event (ClutterActor       *actor,
+                                   ClutterButtonEvent *event)
+{
+  StClickable *self = ST_CLICKABLE (actor);
+
+  if (event->button != self->priv->initiating_button || event->click_count != 1)
+    return FALSE;
+
+  if (!self->priv->held)
+    return TRUE;
+
+  self->priv->held = FALSE;
+  clutter_ungrab_pointer ();
+
+  if (!st_clickable_contains (self, event->source))
+    return FALSE;
+
+  set_pressed (self, FALSE);
+
+  g_signal_emit (G_OBJECT (self), st_clickable_signals[CLICKED], 0, event);
+
+  return TRUE;
+}
+
+/**
+ * st_clickable_fake_release:
+ * @box:
+ *
+ * If this widget is holding a pointer grab, this function will
+ * will ungrab it, and reset the pressed state.  The effect is
+ * similar to if the user had released the mouse button, but without
+ * emitting the clicked signal.
+ *
+ * This function is useful if for example you want to do something after the user
+ * is holding the mouse button for a given period of time, breaking the
+ * grab.
+ */
+void
+st_clickable_fake_release (StClickable *self)
+{
+  if (!self->priv->held)
+    return;
+
+  self->priv->held = FALSE;
+  clutter_ungrab_pointer ();
+
+  set_pressed (self, FALSE);
+}
+
+static void
+st_clickable_set_property (GObject         *object,
+                           guint            prop_id,
+                           const GValue    *value,
+                           GParamSpec      *pspec)
+{
+  StClickable *self = ST_CLICKABLE (object);
+
+  switch (prop_id)
+    {
+    case PROP_ACTIVE:
+      set_active (self, g_value_get_boolean (value));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+st_clickable_get_property (GObject         *object,
+                           guint            prop_id,
+                           GValue          *value,
+                           GParamSpec      *pspec)
+{
+  StClickable *self = ST_CLICKABLE (object);
+
+  switch (prop_id)
+    {
+    case PROP_ACTIVE:
+      g_value_set_boolean (value, self->priv->active);
+      break;
+    case PROP_PRESSED:
+      g_value_set_boolean (value, self->priv->pressed);
+      break;
+    case PROP_HOVER:
+      g_value_set_boolean (value, self->priv->hover);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+st_clickable_class_init (StClickableClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+  ClutterActorClass *actor_class = CLUTTER_ACTOR_CLASS (klass);
+
+  gobject_class->get_property = st_clickable_get_property;
+  gobject_class->set_property = st_clickable_set_property;
+
+  actor_class->enter_event = st_clickable_enter_event;
+  actor_class->leave_event = st_clickable_leave_event;
+  actor_class->button_press_event = st_clickable_button_press_event;
+  actor_class->button_release_event = st_clickable_button_release_event;
+
+  /**
+   * StClickable::clicked
+   * @box: The #StClickable
+   *
+   * This signal is emitted when the button should take the action
+   * associated with button click+release.
+   */
+  st_clickable_signals[CLICKED] =
+    g_signal_new ("clicked",
+                  G_TYPE_FROM_CLASS (klass),
+                  G_SIGNAL_RUN_LAST,
+                  0,
+                  NULL, NULL,
+                  g_cclosure_marshal_VOID__BOXED,
+                  G_TYPE_NONE, 1, CLUTTER_TYPE_EVENT);
+
+  /**
+   * StClickable:active
+   *
+   * The property allows the button to be used as a "toggle button"; it's up to the
+   * application to update the active property in response to the activate signal;
+   * it doesn't happen automatically.
+   */
+  g_object_class_install_property (gobject_class,
+                                   PROP_ACTIVE,
+                                   g_param_spec_boolean ("active",
+                                                         "Active",
+                                                         "Whether the button persistently active",
+                                                         FALSE,
+                                                         G_PARAM_READWRITE));
+
+  /**
+   * StClickable:hover
+   *
+   * This property tracks whether the mouse is over the button; note this
+   * state is independent of whether the button is pressed.
+   */
+  g_object_class_install_property (gobject_class,
+                                   PROP_HOVER,
+                                   g_param_spec_boolean ("hover",
+                                                         "Hovering state",
+                                                         "Whether the mouse is over the button",
+                                                         FALSE,
+                                                         G_PARAM_READABLE));
+
+  /**
+   * StClickable:pressed
+   *
+   * This property tracks whether the button should have a "pressed in"
+   * effect.
+   */
+  g_object_class_install_property (gobject_class,
+                                   PROP_PRESSED,
+                                   g_param_spec_boolean ("pressed",
+                                                         "Pressed state",
+                                                         "Whether the button is currently pressed",
+                                                         FALSE,
+                                                         G_PARAM_READABLE));
+
+  g_type_class_add_private (gobject_class, sizeof (StClickablePrivate));
+}
+
+static void
+st_clickable_init (StClickable *self)
+{
+  self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, ST_TYPE_CLICKABLE,
+                                            StClickablePrivate);
+}
diff --git a/src/st/st-clickable.h b/src/st/st-clickable.h
new file mode 100644
index 0000000..1c59447
--- /dev/null
+++ b/src/st/st-clickable.h
@@ -0,0 +1,35 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+#ifndef __ST_CLICKABLE_H__
+#define __ST_CLICKABLE_H__
+
+#include "st-bin.h"
+
+#define ST_TYPE_CLICKABLE                 (st_clickable_get_type ())
+#define ST_CLICKABLE(obj)                 (G_TYPE_CHECK_INSTANCE_CAST ((obj), ST_TYPE_CLICKABLE, StClickable))
+#define ST_CLICKABLE_CLASS(klass)         (G_TYPE_CHECK_CLASS_CAST ((klass), ST_TYPE_CLICKABLE, StClickableClass))
+#define ST_IS_CLICKABLE(obj)              (G_TYPE_CHECK_INSTANCE_TYPE ((obj), ST_TYPE_CLICKABLE))
+#define ST_IS_CLICKABLE_CLASS(klass)      (G_TYPE_CHECK_CLASS_TYPE ((klass), ST_TYPE_CLICKABLE))
+#define ST_CLICKABLE_GET_CLASS(obj)       (G_TYPE_INSTANCE_GET_CLASS ((obj), ST_TYPE_CLICKABLE, StClickableClass))
+
+typedef struct _StClickable        StClickable;
+typedef struct _StClickableClass   StClickableClass;
+
+typedef struct _StClickablePrivate StClickablePrivate;
+
+struct _StClickable
+{
+    StBin parent;
+
+    StClickablePrivate *priv;
+};
+
+struct _StClickableClass
+{
+    StBinClass parent_class;
+};
+
+GType st_clickable_get_type (void) G_GNUC_CONST;
+
+void st_clickable_fake_release (StClickable *box);
+
+#endif /* __ST_CLICKABLE_H__ */