[gnome-builder] egg: add EggElasticBin

[Christian Hergert <chergert src gnome org>]

commit 4929739fd170ed87fcbdcb94f33288ab59cb4677
Author: Christian Hergert <chergert redhat com>
Date:   Fri Apr 7 14:28:35 2017 -0700

    egg: add EggElasticBin
    
    This is a simple bin that animates between vertical sizes.

 contrib/egg/Makefile.am       |    2 +
 contrib/egg/egg-elastic-bin.c |  278 +++++++++++++++++++++++++++++++++++++++++
 contrib/egg/egg-elastic-bin.h |   44 +++++++
 3 files changed, 324 insertions(+), 0 deletions(-)
---
diff --git a/contrib/egg/Makefile.am b/contrib/egg/Makefile.am
index 7772555..6a97101 100644
--- a/contrib/egg/Makefile.am
+++ b/contrib/egg/Makefile.am
@@ -15,6 +15,7 @@ headers_DATA =                        \
        egg-column-layout.h           \
        egg-counter.h                 \
        egg-date-time.h               \
+       egg-elastic-bin.h             \
        egg-empty-state.h             \
        egg-entry-box.h               \
        egg-file-chooser-entry.h      \
@@ -51,6 +52,7 @@ libegg_private_la_SOURCES =           \
        egg-column-layout.c           \
        egg-counter.c                 \
        egg-date-time.c               \
+       egg-elastic-bin.c             \
        egg-empty-state.c             \
        egg-entry-box.c               \
        egg-file-chooser-entry.c      \
diff --git a/contrib/egg/egg-elastic-bin.c b/contrib/egg/egg-elastic-bin.c
new file mode 100644
index 0000000..3e90c36
--- /dev/null
+++ b/contrib/egg/egg-elastic-bin.c
@@ -0,0 +1,278 @@
+/* egg-elastic-bin.c
+ *
+ * Copyright (C) 2017 Christian Hergert <chergert redhat com>
+ *
+ * This file is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 2.1 of the License, or (at your option)
+ * any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define G_LOG_DOMAIN "egg-elastic-bin"
+
+#include "egg-animation.h"
+#include "egg-elastic-bin.h"
+
+#define MM_PER_SECOND       (100.0)
+#define MIN_FRAMES_PER_ANIM (5)
+#define MAX_FRAMES_PER_ANIM (500)
+
+#if 0
+# define _TRACE_LEVEL (1<<G_LOG_LEVEL_USER_SHIFT)
+# define _TRACE(...) do { g_log(G_LOG_DOMAIN, _TRACE_LEVEL, __VA_ARGS__); } while (0)
+# define TRACE_MSG(m,...) _TRACE("   MSG: %s():%u: "m, G_STRFUNC, __LINE__, __VA_ARGS__)
+# define ENTRY _TRACE(" ENTRY: %s(): %u", G_STRFUNC, __LINE__)
+# define EXIT do { _TRACE("  EXIT: %s(): %u", G_STRFUNC, __LINE__); return; } while (0)
+# define RETURN(r) do { _TRACE("  EXIT: %s(): %u", G_STRFUNC, __LINE__); return (r); } while (0)
+#else
+# define TRACE_MSG(m,...) do { } while (0)
+# define ENTRY            do { } while (0)
+# define EXIT             return
+# define RETURN(r)        return (r)
+#endif
+
+typedef struct
+{
+  GtkAdjustment *hadj;
+  EggAnimation  *hanim;
+  gint           cached_min_height;
+  gint           cached_nat_height;
+} EggElasticBinPrivate;
+
+G_DEFINE_TYPE_WITH_PRIVATE (EggElasticBin, egg_elastic_bin, GTK_TYPE_BIN)
+
+static void
+egg_elastic_bin_cancel_animation (EggElasticBin *self)
+{
+  EggElasticBinPrivate *priv = egg_elastic_bin_get_instance_private (self);
+
+  ENTRY;
+
+  g_assert (EGG_IS_ELASTIC_BIN (self));
+
+  if (priv->hanim != NULL)
+    {
+      EggAnimation *anim = priv->hanim;
+
+      g_object_remove_weak_pointer (G_OBJECT (priv->hanim), (gpointer *)&priv->hanim);
+      priv->hanim = NULL;
+
+      egg_animation_stop (anim);
+    }
+
+  EXIT;
+}
+
+static guint
+egg_elastic_bin_calculate_duration (EggElasticBin *self,
+                                    gdouble        from_value,
+                                    gdouble        to_value)
+{
+  GdkDisplay *display;
+  GdkMonitor *monitor;
+  GdkWindow *window;
+
+  g_assert (EGG_IS_ELASTIC_BIN (self));
+  g_assert (from_value >= 0.0);
+  g_assert (to_value >= 0.0);
+
+  if (NULL != (display = gtk_widget_get_display (GTK_WIDGET (self))) &&
+      NULL != (window = gtk_widget_get_window (GTK_WIDGET (self))) &&
+      NULL != (monitor = gdk_display_get_monitor_at_window (display, window)))
+    return egg_animation_calculate_duration (monitor, from_value, to_value);
+
+  return 0;
+}
+
+static void
+egg_elastic_bin_animate_to (EggElasticBin *self,
+                            gdouble        value)
+{
+  EggElasticBinPrivate *priv = egg_elastic_bin_get_instance_private (self);
+  guint duration;
+
+  ENTRY;
+
+  g_assert (EGG_IS_ELASTIC_BIN (self));
+
+  egg_elastic_bin_cancel_animation (self);
+
+  duration = egg_elastic_bin_calculate_duration (self,
+                                                 gtk_adjustment_get_value (priv->hadj),
+                                                 value);
+
+  TRACE_MSG ("Duration is %u milliseconds", duration);
+
+  priv->hanim = egg_object_animate (priv->hadj,
+                                    EGG_ANIMATION_EASE_OUT_CUBIC,
+                                    duration,
+                                    gtk_widget_get_frame_clock (GTK_WIDGET (self)),
+                                    "value", value,
+                                    NULL);
+  g_object_add_weak_pointer (G_OBJECT (priv->hanim), (gpointer *)&priv->hanim);
+
+  EXIT;
+}
+
+static void
+egg_elastic_bin_get_preferred_height_for_width (GtkWidget *widget,
+                                                gint       width,
+                                                gint      *min_height,
+                                                gint      *nat_height)
+{
+  EggElasticBin *self = (EggElasticBin *)widget;
+  EggElasticBinPrivate *priv = egg_elastic_bin_get_instance_private (self);
+
+  ENTRY;
+
+  TRACE_MSG ("width=%d", width);
+
+  g_assert (EGG_IS_ELASTIC_BIN (self));
+
+  /*
+   * We must always chain up to the parent get_preferred_height_for_width()
+   * so that we can detect changes while we are animating.
+   */
+
+  GTK_WIDGET_CLASS (egg_elastic_bin_parent_class)->get_preferred_height_for_width (widget, width, 
min_height, nat_height);
+
+  /*
+   * If we are animating the widget, and the size request hasn't changed since
+   * our last animation frame, go ahead and process that now.
+   */
+
+  if (*min_height == priv->cached_min_height &&
+      *nat_height == priv->cached_nat_height &&
+      priv->hanim != NULL)
+    {
+      *min_height = priv->cached_min_height;
+      *nat_height = (gint)gtk_adjustment_get_value (priv->hadj);
+
+      TRACE_MSG ("Fast path min=%d nat=%d", *min_height, *nat_height);
+
+      if (*nat_height == priv->cached_nat_height)
+        egg_elastic_bin_cancel_animation (self);
+
+      EXIT;
+    }
+
+  if (*min_height != priv->cached_min_height || *nat_height != priv->cached_nat_height)
+    {
+      priv->cached_min_height = *min_height;
+      priv->cached_nat_height = *nat_height;
+
+      TRACE_MSG ("New requested height is min=%d nat=%d",
+                 *min_height, *nat_height);
+
+      if (*min_height > (gint)gtk_adjustment_get_value (priv->hadj))
+        gtk_adjustment_set_value (priv->hadj, *min_height);
+
+      *min_height = priv->cached_min_height;
+      *nat_height = (gint)gtk_adjustment_get_value (priv->hadj);
+
+      egg_elastic_bin_animate_to (self, priv->cached_nat_height);
+
+      TRACE_MSG ("!!! min=%d nat=%d", *min_height, *nat_height);
+
+      EXIT;
+    }
+
+  TRACE_MSG ("*** min=%d nat=%d", *min_height, *nat_height);
+
+  EXIT;
+}
+
+static void
+egg_elastic_bin_hadj_value_changed (EggElasticBin *self,
+                                    GtkAdjustment *adj)
+{
+  ENTRY;
+
+  g_assert (EGG_IS_ELASTIC_BIN (self));
+  g_assert (GTK_IS_ADJUSTMENT (adj));
+
+  gtk_widget_queue_resize (GTK_WIDGET (self));
+
+  EXIT;
+}
+
+static void
+egg_elastic_bin_size_allocate (GtkWidget     *widget,
+                               GtkAllocation *allocation)
+{
+  g_assert (GTK_IS_WIDGET (widget));
+  g_assert (allocation != NULL);
+
+  TRACE_MSG ("Allocating %d,%d %dx%d",
+             allocation->x, allocation->y,
+             allocation->width, allocation->height);
+
+  GTK_WIDGET_CLASS (egg_elastic_bin_parent_class)->size_allocate (widget, allocation);
+}
+
+static GtkSizeRequestMode
+egg_elastic_bin_get_request_mode (GtkWidget *widget)
+{
+  return GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH;
+}
+
+static void
+egg_elastic_bin_destroy (GtkWidget *widget)
+{
+  EggElasticBin *self = (EggElasticBin *)widget;
+
+  g_assert (EGG_IS_ELASTIC_BIN (self));
+
+  egg_elastic_bin_cancel_animation (self);
+
+  GTK_WIDGET_CLASS (egg_elastic_bin_parent_class)->destroy (widget);
+}
+
+static void
+egg_elastic_bin_finalize (GObject *object)
+{
+  EggElasticBin *self = (EggElasticBin *)object;
+  EggElasticBinPrivate *priv = egg_elastic_bin_get_instance_private (self);
+
+  g_clear_object (&priv->hadj);
+
+  G_OBJECT_CLASS (egg_elastic_bin_parent_class)->finalize (object);
+}
+
+static void
+egg_elastic_bin_class_init (EggElasticBinClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+
+  object_class->finalize = egg_elastic_bin_finalize;
+
+  widget_class->destroy = egg_elastic_bin_destroy;
+  widget_class->get_preferred_height_for_width = egg_elastic_bin_get_preferred_height_for_width;
+  widget_class->size_allocate = egg_elastic_bin_size_allocate;
+  widget_class->get_request_mode = egg_elastic_bin_get_request_mode;
+
+  gtk_widget_class_set_css_name (widget_class, "elastic");
+}
+
+static void
+egg_elastic_bin_init (EggElasticBin *self)
+{
+  EggElasticBinPrivate *priv = egg_elastic_bin_get_instance_private (self);
+
+  priv->hadj = gtk_adjustment_new (0, 0, G_MAXINT, 1, 1, 1);
+
+  g_signal_connect_object (priv->hadj,
+                           "value-changed",
+                           G_CALLBACK (egg_elastic_bin_hadj_value_changed),
+                           self,
+                           G_CONNECT_SWAPPED);
+}
diff --git a/contrib/egg/egg-elastic-bin.h b/contrib/egg/egg-elastic-bin.h
new file mode 100644
index 0000000..dcd0805
--- /dev/null
+++ b/contrib/egg/egg-elastic-bin.h
@@ -0,0 +1,44 @@
+/* egg-elastic-bin.h
+ *
+ * Copyright (C) 2017 Christian Hergert <chergert redhat com>
+ *
+ * This file is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 2.1 of the License, or (at your option)
+ * any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef EGG_ELASTIC_BIN_H
+#define EGG_ELASTIC_BIN_H
+
+#include <gtk/gtk.h>
+
+G_BEGIN_DECLS
+
+#define EGG_TYPE_ELASTIC_BIN (egg_elastic_bin_get_type())
+
+G_DECLARE_DERIVABLE_TYPE (EggElasticBin, egg_elastic_bin, EGG, ELASTIC_BIN, GtkBin)
+
+struct _EggElasticBinClass
+{
+  GtkBinClass parent_class;
+
+  gpointer _reserved1;
+  gpointer _reserved2;
+  gpointer _reserved3;
+  gpointer _reserved4;
+};
+
+GtkWidget *egg_elastic_bin_new (void);
+
+G_END_DECLS
+
+#endif /* EGG_ELASTIC_BIN_H */