[gtk+] gtk3-demo: Add another overlay demo

[Matthias Clasen <matthiasc src gnome org>]

commit 763bf27d9c5867328ab40872b3aaff77bc874769
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Jul 28 22:47:07 2015 -0400

    gtk3-demo: Add another overlay demo

 demos/gtk-demo/Makefile.am        |    1 +
 demos/gtk-demo/decor1.png         |  Bin 0 -> 17170 bytes
 demos/gtk-demo/decor2.png         |  Bin 0 -> 17248 bytes
 demos/gtk-demo/demo.gresource.xml |    5 ++
 demos/gtk-demo/overlay.c          |    4 +-
 demos/gtk-demo/overlay2.c         |  105 +++++++++++++++++++++++++++++++++++++
 6 files changed, 113 insertions(+), 2 deletions(-)
---
diff --git a/demos/gtk-demo/Makefile.am b/demos/gtk-demo/Makefile.am
index f03f1c6..2067229 100644
--- a/demos/gtk-demo/Makefile.am
+++ b/demos/gtk-demo/Makefile.am
@@ -43,6 +43,7 @@ demos_base =                                  \
        offscreen_window.c                      \
        offscreen_window2.c                     \
        overlay.c                               \
+       overlay2.c                              \
        panes.c                                 \
        pickers.c                               \
        pixbufs.c                               \
diff --git a/demos/gtk-demo/decor1.png b/demos/gtk-demo/decor1.png
new file mode 100644
index 0000000..61d2edc
Binary files /dev/null and b/demos/gtk-demo/decor1.png differ
diff --git a/demos/gtk-demo/decor2.png b/demos/gtk-demo/decor2.png
new file mode 100644
index 0000000..6d5a6bf
Binary files /dev/null and b/demos/gtk-demo/decor2.png differ
diff --git a/demos/gtk-demo/demo.gresource.xml b/demos/gtk-demo/demo.gresource.xml
index 2ac7dd5..ed879cc 100644
--- a/demos/gtk-demo/demo.gresource.xml
+++ b/demos/gtk-demo/demo.gresource.xml
@@ -149,6 +149,7 @@
     <file>offscreen_window.c</file>
     <file>offscreen_window2.c</file>
     <file>overlay.c</file>
+    <file>overlay2.c</file>
     <file>pagesetup.c</file>
     <file>panes.c</file>
     <file>pickers.c</file>
@@ -196,4 +197,8 @@
   <gresource prefix="/filtermodel">
     <file>filtermodel.ui</file>
   </gresource>
+  <gresource prefix="/overlay2">
+    <file>decor1.png</file>
+    <file>decor2.png</file>
+  </gresource>
 </gresources>
diff --git a/demos/gtk-demo/overlay.c b/demos/gtk-demo/overlay.c
index f6d67ed..5861e11 100644
--- a/demos/gtk-demo/overlay.c
+++ b/demos/gtk-demo/overlay.c
@@ -1,4 +1,4 @@
-/* Overlay
+/* Overlay/Interactive Overlay
  *
  * Shows widgets in static positions over a main widget.
  *
@@ -33,7 +33,7 @@ do_overlay (GtkWidget *do_widget)
 
       window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
       gtk_window_set_default_size (GTK_WINDOW (window), 500, 510);
-      gtk_window_set_title (GTK_WINDOW (window), "Overlay");
+      gtk_window_set_title (GTK_WINDOW (window), "Interactive Overlay");
 
       overlay = gtk_overlay_new ();
       grid = gtk_grid_new ();
diff --git a/demos/gtk-demo/overlay2.c b/demos/gtk-demo/overlay2.c
new file mode 100644
index 0000000..a119c92
--- /dev/null
+++ b/demos/gtk-demo/overlay2.c
@@ -0,0 +1,105 @@
+/* Overlay/Decorative Overlay
+ *
+ * Another example of an overlay with some decorative
+ * and some interactive controls.
+ */
+
+#include <gtk/gtk.h>
+
+static GtkTextTag *tag;
+
+static void
+margin_changed (GtkAdjustment *adjustment,
+                GtkTextView   *text)
+{
+  gint value;
+
+  value = (gint)gtk_adjustment_get_value (adjustment);
+  gtk_text_view_set_left_margin (GTK_TEXT_VIEW (text), value);
+  g_object_set (tag, "pixels-above-lines", value, NULL);
+}
+
+GtkWidget *
+do_overlay2 (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
+    {
+      GtkWidget *overlay;
+      GtkWidget *sw;
+      GtkWidget *text;
+      GtkWidget *image;
+      GtkWidget *scale;
+      GtkTextBuffer *buffer;
+      GtkTextIter start, end;
+      GtkAdjustment *adjustment;
+
+      window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+      gtk_window_set_default_size (GTK_WINDOW (window), 500, 510);
+      gtk_window_set_title (GTK_WINDOW (window), "Decorative Overlay");
+
+      overlay = gtk_overlay_new ();
+      sw = gtk_scrolled_window_new (NULL, NULL);
+      gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
+                                      GTK_POLICY_AUTOMATIC,
+                                      GTK_POLICY_AUTOMATIC);
+      text = gtk_text_view_new ();
+      buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (text));
+
+      gtk_text_buffer_set_text (buffer, "Dear diary...", -1);
+
+      tag = gtk_text_buffer_create_tag (buffer, "top-margin",
+                                        "pixels-above-lines", 0,
+                                        NULL);
+      gtk_text_buffer_get_start_iter (buffer, &start);
+      end = start;
+      gtk_text_iter_forward_word_end (&end);
+      gtk_text_buffer_apply_tag (buffer, tag, &start, &end);
+
+      gtk_container_add (GTK_CONTAINER (window), overlay);
+      gtk_container_add (GTK_CONTAINER (overlay), sw);
+      gtk_container_add (GTK_CONTAINER (sw), text);
+
+      g_signal_connect (window, "destroy",
+                        G_CALLBACK (gtk_widget_destroyed), &window);
+
+      image = gtk_image_new_from_resource ("/overlay2/decor1.png");
+      gtk_overlay_add_overlay (GTK_OVERLAY (overlay), image);
+      gtk_overlay_set_overlay_pass_through (GTK_OVERLAY (overlay), image, TRUE);
+      gtk_widget_set_halign (image, GTK_ALIGN_START);
+      gtk_widget_set_valign (image, GTK_ALIGN_START);
+
+      image = gtk_image_new_from_resource ("/overlay2/decor2.png");
+      gtk_overlay_add_overlay (GTK_OVERLAY (overlay), image);
+      gtk_overlay_set_overlay_pass_through (GTK_OVERLAY (overlay), image, TRUE);
+      gtk_widget_set_halign (image, GTK_ALIGN_END);
+      gtk_widget_set_valign (image, GTK_ALIGN_END);
+
+      adjustment = gtk_adjustment_new (0, 0, 100, 1, 1, 0);
+      g_signal_connect (adjustment, "value-changed",
+                        G_CALLBACK (margin_changed), text);
+
+      scale = gtk_scale_new (GTK_ORIENTATION_HORIZONTAL, adjustment);
+      gtk_scale_set_draw_value (GTK_SCALE (scale), FALSE);
+      gtk_widget_set_size_request (scale, 120, -1);
+      gtk_widget_set_margin_start (scale, 20);
+      gtk_widget_set_margin_end (scale, 20);
+      gtk_widget_set_margin_bottom (scale, 20);
+      gtk_overlay_add_overlay (GTK_OVERLAY (overlay), scale);
+      gtk_widget_set_halign (scale, GTK_ALIGN_START);
+      gtk_widget_set_valign (scale, GTK_ALIGN_END);
+      gtk_widget_set_tooltip_text (scale, "Margin");
+
+      gtk_adjustment_set_value (adjustment, 100);
+
+      gtk_widget_show_all (overlay);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_widget_destroy (window);
+
+  return window;
+}