[gtk/popup-shadow-width] Add a test for popover shadows

[Matthias Clasen <matthiasc src gnome org>]

commit ee4879eb991523e2208ec06a41025470f8b01d03
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Feb 13 15:46:00 2021 -0500

    Add a test for popover shadows

 tests/testpopup.c | 113 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 113 insertions(+)
---
diff --git a/tests/testpopup.c b/tests/testpopup.c
new file mode 100644
index 0000000000..ca6fbcb99e
--- /dev/null
+++ b/tests/testpopup.c
@@ -0,0 +1,113 @@
+#include <gtk/gtk.h>
+
+static void
+update_shadow (GObject    *object,
+               GParamSpec *pspec,
+               GtkWidget  *widget)
+{
+  const char *classes[] = {
+    "no-shadow",
+    "shadow1",
+    "shadow2",
+    "shadow3",
+    "shadow4",
+  };
+  guint selected;
+
+  selected = gtk_drop_down_get_selected (GTK_DROP_DOWN (object));
+  g_assert (selected < G_N_ELEMENTS (classes));
+
+  for (int i = 0; i < G_N_ELEMENTS (classes); i++)
+    gtk_widget_remove_css_class (widget, classes[i]);
+
+  gtk_widget_add_css_class (widget, classes[selected]);
+}
+
+static const char css[] =
+ "popover.no-shadow > contents { box-shadow: none; }\n"
+ "popover.shadow1 > contents { box-shadow: 6px 6px rgba(255,0,0,0.5); }\n"
+ "popover.shadow2 > contents { box-shadow: -6px -6px rgba(255,0,0,0.5), 6px 6px rgba(255,0,255,0.5); }\n"
+ "popover.shadow3 > contents { box-shadow: -6px -6px rgba(255,0,0,0.5), 18px 18px rgba(255,0,255,0.5); }\n"
+ "popover.shadow4 > contents { box-shadow: -18px -18px rgba(255,0,0,0.5), 18px 18px rgba(255,0,255,0.5); 
}\n";
+
+int
+main (int argc, char *argv[])
+{
+  GtkWidget *window;
+  GtkWidget *box;
+  GtkWidget *button;
+  GtkWidget *popover;
+  GtkWidget *box2;
+  GtkWidget *box3;
+  GtkWidget *checkbox;
+  GtkWidget *dropdown;
+  GtkWidget *dropdown2;
+  GtkCssProvider *provider;
+
+  gtk_init ();
+
+  provider = gtk_css_provider_new ();
+  gtk_css_provider_load_from_data (provider, css, -1);
+
+  gtk_style_context_add_provider_for_display (gdk_display_get_default (),
+                                              GTK_STYLE_PROVIDER (provider),
+                                              800);
+
+  window = gtk_window_new ();
+  box = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 10);
+  g_object_set (box,
+                "margin-top", 20,
+                "margin-bottom", 20,
+                "margin-start", 20,
+                "margin-end", 20,
+                NULL);
+
+  button = gtk_menu_button_new ();
+
+  gtk_widget_set_halign (button, GTK_ALIGN_CENTER);
+  gtk_widget_set_valign (button, GTK_ALIGN_CENTER);
+
+  gtk_box_append (GTK_BOX (box), button);
+
+  popover = gtk_popover_new ();
+  box2 = gtk_box_new (GTK_ORIENTATION_VERTICAL, 10);
+  gtk_popover_set_child (GTK_POPOVER (popover), box2);
+
+  gtk_box_append (GTK_BOX (box2), gtk_label_new ("First item"));
+  gtk_box_append (GTK_BOX (box2), gtk_label_new ("Second item"));
+  gtk_box_append (GTK_BOX (box2), gtk_label_new ("Third item"));
+
+  gtk_menu_button_set_popover (GTK_MENU_BUTTON (button), popover);
+
+  box3 = gtk_box_new (GTK_ORIENTATION_VERTICAL, 10);
+  dropdown = gtk_drop_down_new_from_strings ((const char*[]){ "Left", "Right", "Top", "Bottom", NULL });
+  gtk_drop_down_set_selected (GTK_DROP_DOWN (dropdown), 3);
+
+  checkbox = gtk_check_button_new_with_label ("Arrow");
+
+  dropdown2 = gtk_drop_down_new_from_strings ((const char*[]){ "No Shadow", "Shadow 1", "Shadow 2", "Shadow 
3", "Shadow 4", NULL });
+
+  gtk_box_append (GTK_BOX (box3), checkbox);
+  gtk_box_append (GTK_BOX (box3), dropdown);
+  gtk_box_append (GTK_BOX (box3), dropdown2);
+
+  gtk_box_append (GTK_BOX (box), box3);
+
+  g_object_bind_property (checkbox, "active",
+                          popover, "has-arrow",
+                          G_BINDING_SYNC_CREATE);
+  g_object_bind_property (dropdown, "selected",
+                          popover, "position",
+                          G_BINDING_SYNC_CREATE);
+  g_signal_connect (dropdown2, "notify::selected",
+                    G_CALLBACK (update_shadow), popover);
+
+  gtk_window_set_child (GTK_WINDOW (window), box);
+
+  gtk_window_present (GTK_WINDOW (window));
+
+  while (g_list_model_get_n_items (gtk_window_get_toplevels ()) > 0)
+    g_main_context_iteration (NULL, TRUE);
+
+  return 0;
+}