event-controler: Add UI feedback for long-press

style and colors of the progress feedback are subject to change

Signed-off-by: Carlos Garnacho <carlos@lanedo.com>
Acked-by: Simon Schampijer <simon@laptop.org>

src/sugar3/event-controller/sugar-long-press-controller.c

@@ -23,6 +23,8 @@
 
 #define DEFAULT_THRESHOLD 32
 #define DEFAULT_TIMEOUT   800
+#define ANIM_WINDOW_WIDTH 100
+#define ARC_LINE_WIDTH    10
 
 typedef struct _SugarLongPressControllerPriv SugarLongPressControllerPriv;
 
@@ -36,8 +38,13 @@ struct _SugarLongPressControllerPriv
 {
   GdkDevice *device;
   GdkEventSequence *sequence;
+  GtkWidget *anim_window;
+  gint64 start_time;
   gint x;
   gint y;
+  gint root_x;
+  gint root_y;
+  guint anim_id;
   guint timeout_id;
   guint threshold;
   guint timeout;
@@ -60,6 +67,7 @@ sugar_long_press_controller_init (SugarLongPressController *controller)
   priv->threshold = DEFAULT_THRESHOLD;
   priv->timeout = DEFAULT_TIMEOUT;
   priv->x = priv->y = -1;
+  priv->root_x = priv->root_y = -1;
 }
 
 static void
@@ -75,6 +83,7 @@ _sugar_long_press_controller_unset_device (SugarLongPressController *controller)
 
   priv->sequence = NULL;
   priv->x = priv->y = -1;
+  priv->root_x = priv->root_y = -1;
   priv->cancelled = priv->triggered = FALSE;
 }
 
@@ -83,6 +92,16 @@ _sugar_long_press_controller_cancel (SugarLongPressController *controller)
 {
   SugarLongPressControllerPriv *priv = controller->_priv;
 
+  if (priv->anim_id)
+    {
+      g_source_remove (priv->anim_id);
+      priv->anim_id = 0;
+    }
+
+  if (priv->anim_window &&
+      gtk_widget_get_visible (priv->anim_window))
+    gtk_widget_hide (priv->anim_window);
+
   if (priv->timeout_id)
     {
       g_source_remove (priv->timeout_id);
@@ -151,6 +170,139 @@ sugar_long_press_controller_finalize (GObject *object)
   G_OBJECT_CLASS (sugar_long_press_controller_parent_class)->finalize (object);
 }
 
+static void
+_stroke_progress_notification (cairo_t *cr,
+                               gdouble  progress)
+{
+  cairo_set_line_width (cr, ARC_LINE_WIDTH);
+  cairo_arc (cr,
+             ANIM_WINDOW_WIDTH / 2,
+             ANIM_WINDOW_WIDTH / 2,
+             ANIM_WINDOW_WIDTH / 2 - ARC_LINE_WIDTH / 2,
+             - G_PI_2, (2 * G_PI * progress) - G_PI_2);
+  cairo_stroke (cr);
+}
+
+static gboolean
+_sugar_long_press_anim_draw (GtkWidget                *widget,
+                             cairo_t                  *cr,
+                             SugarLongPressController *controller)
+{
+  SugarLongPressControllerPriv *priv = controller->_priv;
+  gdouble progress;
+  gint64 diff_msec;
+
+  diff_msec = (g_get_monotonic_time () - priv->start_time) / 1000;
+  progress = (gdouble) diff_msec / priv->timeout;
+
+  cairo_save (cr);
+  cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+  cairo_set_source_rgba (cr, 0, 0, 0, 0);
+  cairo_paint (cr);
+  cairo_restore (cr);
+
+  _stroke_progress_notification (cr, progress);
+
+  return TRUE;
+}
+
+static void
+_sugar_long_press_controller_update_shape (GtkWidget                *widget,
+                                           SugarLongPressController *controller)
+{
+  cairo_surface_t *surface;
+  cairo_region_t *region;
+  cairo_t *cr;
+
+  surface = cairo_image_surface_create (CAIRO_FORMAT_A1,
+                                        ANIM_WINDOW_WIDTH,
+                                        ANIM_WINDOW_WIDTH);
+  cr = cairo_create (surface);
+  _stroke_progress_notification (cr, 1.0);
+  cairo_destroy (cr);
+
+  region = gdk_cairo_region_create_from_surface (surface);
+  cairo_surface_destroy (surface);
+
+  gtk_widget_shape_combine_region (widget, region);
+  cairo_region_destroy (region);
+}
+
+static gboolean
+_sugar_long_press_anim_timeout (gpointer user_data)
+{
+  SugarLongPressController *controller = user_data;
+  SugarLongPressControllerPriv *priv = controller->_priv;
+  GtkWidget *widget;
+
+  g_object_get (controller, "widget", &widget, NULL);
+
+  if (!widget)
+    {
+      priv->anim_id = 0;
+      return FALSE;
+    }
+
+  if (priv->anim_window &&
+      gtk_widget_get_screen (widget) !=
+      gtk_widget_get_screen (priv->anim_window))
+    {
+      gtk_widget_destroy (priv->anim_window);
+      priv->anim_window = NULL;
+    }
+
+  if (!priv->anim_window)
+    {
+      GdkScreen *screen;
+      GdkVisual *rgba_visual;
+
+      priv->anim_window = gtk_window_new (GTK_WINDOW_POPUP);
+      gtk_widget_set_app_paintable (priv->anim_window, TRUE);
+      gtk_widget_input_shape_combine_region (priv->anim_window, NULL);
+      gtk_window_set_type_hint (GTK_WINDOW (priv->anim_window),
+                                GDK_WINDOW_TYPE_HINT_UTILITY);
+
+      screen = gtk_widget_get_screen (widget);
+      rgba_visual = gdk_screen_get_rgba_visual (screen);
+
+      gtk_window_set_screen (GTK_WINDOW (priv->anim_window), screen);
+
+      if (rgba_visual)
+        {
+          GdkRGBA bg = { 0, 0, 0, 0 };
+
+          gtk_widget_set_visual (priv->anim_window, rgba_visual);
+          gtk_widget_override_background_color (priv->anim_window, 0, &bg);
+        }
+      else
+        _sugar_long_press_controller_update_shape (priv->anim_window,
+                                                   controller);
+      g_signal_connect (priv->anim_window, "draw",
+                        G_CALLBACK (_sugar_long_press_anim_draw),
+                        controller);
+    }
+
+  if (!gtk_widget_get_visible (priv->anim_window))
+    {
+      gtk_window_move (GTK_WINDOW (priv->anim_window),
+                       priv->root_x - (ANIM_WINDOW_WIDTH / 2),
+                       priv->root_y - (ANIM_WINDOW_WIDTH / 2));
+      gtk_window_resize (GTK_WINDOW (priv->anim_window),
+                         ANIM_WINDOW_WIDTH, ANIM_WINDOW_WIDTH);
+      gtk_widget_show (priv->anim_window);
+
+      priv->anim_id =
+        gdk_threads_add_timeout (20, _sugar_long_press_anim_timeout,
+                                 controller);
+      return FALSE;
+    }
+  else
+    {
+      gtk_widget_queue_draw (priv->anim_window);
+      return TRUE;
+    }
+}
+
 static gboolean
 _sugar_long_press_controller_timeout (gpointer user_data)
 {
@@ -232,10 +384,17 @@ sugar_long_press_controller_handle_event (SugarEventController *controller,
     {
     case GDK_TOUCH_BEGIN:
       priv->device = g_object_ref (device);
+      priv->start_time = g_get_monotonic_time ();
       priv->x = event->touch.x;
       priv->y = event->touch.y;
+      priv->root_x = event->touch.x_root;
+      priv->root_y = event->touch.y_root;
       priv->sequence = sequence;
 
+      priv->anim_id =
+        gdk_threads_add_timeout (100,
+                                 _sugar_long_press_anim_timeout,
+                                 controller);
       priv->timeout_id =
         gdk_threads_add_timeout (priv->timeout,
                                  _sugar_long_press_controller_timeout,