From 6b733d294354c349b4b5ef7d689c0b2ef162f797 Mon Sep 17 00:00:00 2001
From: Benjamin Otte <otte@redhat.com>
Date: Thu, 19 Aug 2021 03:14:59 +0200
Subject: [PATCH] gtk-demo: Make clipboard demo paste from clipboard

The old code was just pasting local clipboard data that we put there
ourselves and was causing criticals on remote clipboard data. Now the
code does the proper async paste.
---
 demos/gtk-demo/demoimage.c | 44 ++++++++++++++++++++++++++++----------
 1 file changed, 33 insertions(+), 11 deletions(-)

diff --git a/demos/gtk-demo/demoimage.c b/demos/gtk-demo/demoimage.c
index 8fdc4257a5..dc5776cc5b 100644
--- a/demos/gtk-demo/demoimage.c
+++ b/demos/gtk-demo/demoimage.c
@@ -146,24 +146,46 @@ copy_image (GtkWidget *widget,
     g_object_unref (paintable);
 }
 
+static void
+paste_image_cb (GObject      *source,
+                GAsyncResult *result,
+                gpointer      data)
+{
+  GdkClipboard *clipboard = GDK_CLIPBOARD (source);
+  DemoImage *demo = DEMO_IMAGE (data);
+  const GValue *value;
+
+  value = gdk_clipboard_read_value_finish (clipboard, result, NULL);
+  if (value == NULL)
+    {
+      gtk_widget_error_bell (GTK_WIDGET (demo));
+      g_object_unref (demo);
+      return;
+    }
+
+  gtk_image_set_from_paintable (GTK_IMAGE (demo->image), g_value_get_object (value));
+  g_object_unref (demo);
+}
+
 static void
 paste_image (GtkWidget *widget,
              const char *action_name,
              GVariant *parameter)
 {
   GdkClipboard *clipboard = gtk_widget_get_clipboard (widget);
-  DemoImage *demo = DEMO_IMAGE (widget);
-  GdkContentProvider *content = gdk_clipboard_get_content (clipboard);
-  GValue value = G_VALUE_INIT;
-  GdkPaintable *paintable;
+  GType type;
 
-  g_value_init (&value, GDK_TYPE_PAINTABLE);
-  if (!gdk_content_provider_get_value (content, &value, NULL))
-    return;
-
-  paintable = GDK_PAINTABLE (g_value_get_object (&value));
-  gtk_image_set_from_paintable (GTK_IMAGE (demo->image), paintable);
-  g_value_unset (&value);
+  if (gdk_content_formats_contain_gtype (gdk_clipboard_get_formats (clipboard), GDK_TYPE_TEXTURE))
+    type = GDK_TYPE_TEXTURE;
+  else
+    type = GDK_TYPE_PAINTABLE;
+
+  gdk_clipboard_read_value_async (clipboard, 
+                                  type,
+                                  G_PRIORITY_DEFAULT,
+                                  NULL,
+                                  paste_image_cb,
+                                  g_object_ref (widget));
 }
 
 static void
-- 
2.30.2