general: Make property extensions gtk version independentnew-properties-extension

Nautilus property extensions to add property pages to the property
dialog was providing a GtkWidget to be modified by extensions.

This makes the extension need to target a specific gtk version, which
with the new gtk versioning might be hard to provide, and it's quite a
bad practice since it requires everyone to be on top of any gtk update.
This is currently holding the work for porting Nautilus to gtk4, since
the Totem extension depends on us having the same gtk+ version, which is
unlikely.

This work makes the extension for providing property extensions not
depend on gtk by providing a plain struct to be filled with data that
later on Nautilus will layout on the UI.

See https://gitlab.gnome.org/GNOME/nautilus/issues/276

1 files changed, 118 insertions, 0 deletions

diff --git a/libnautilus-extension/nautilus-property-page-model-provider.c b/libnautilus-extension/nautilus-property-page-model-provider.c
new file mode 100644
index 000000000..12b0fe711
--- /dev/null
+++ b/libnautilus-extension/nautilus-property-page-model-provider.c
@@ -0,0 +1,118 @@
+/*
+ *  nautilus-property-page-model-provider.c - Interface for Nautilus extensions
+ * *                                      that provide property pages for
+ * *                                      files.
+ *
+ *  Copyright (C) 2003 Novell, Inc.
+ *  Copyright (C) 2018 Red Hat, Inc.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public
+ *  License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ *  Author:  Dave Camp <dave@ximian.com>
+ *           Carlos Soriano <csoriano@redhat.com>
+ *
+ */
+#include "config.h"
+
+#include "nautilus-property-page-model-provider.h"
+#include "nautilus-property-page-model.h"
+
+G_DEFINE_INTERFACE (NautilusPropertyPageModelProvider, nautilus_property_page_model_provider,
+                    G_TYPE_OBJECT)
+
+/**
+ * SECTION:nautilus-property-page-model-provider-interface
+ * @title: NautilusPropertyPageModelProvider
+ * @short_description: Interface to provide a property page
+ *
+ * #NautilusPropertyPageModelProvider allows extension to provide an additional
+ * page for the file properties dialog.
+ */
+
+static void
+nautilus_property_page_model_provider_default_init (NautilusPropertyPageModelProviderInterface *klass)
+{
+    /**
+     * NautilusView::page-model:
+     *
+     * The page model associated with the provider.
+     */
+    g_object_interface_install_property (klass,
+                                         g_param_spec_object ("page-model",
+                                                              "Page model",
+                                                              "The page model associated with the provider",
+                                                              NAUTILUS_TYPE_PROPERTY_PAGE_MODEL,
+                                                              G_PARAM_READWRITE));
+    g_object_interface_install_property (klass,
+                                         g_param_spec_pointer ("files",
+                                                               "Files",
+                                                               "Files to get info from",
+                                                              G_PARAM_READWRITE));
+}
+
+/**
+ * nautilus_property_page_model_provider_get_model:
+ * @provider: a #NautilusPropertyPageModelProvider
+ * @files: (element-type NautilusFileInfo): a #GList of #NautilusFileInfo
+ *
+ * This function is called by Nautilus when it wants property page
+ * items from the extension.
+ *
+ * This function is called in the main thread before a property page
+ * is shown, so it should return quickly.
+ *
+ * Returns: (element-type NautilusPropertyItem) (transfer full): A #GList of allocated #NautilusPropertyItem.
+ */
+NautilusPropertyPageModel *
+nautilus_property_page_model_provider_get_model (NautilusPropertyPageModelProvider *self)
+{
+    NautilusPropertyPageModelProviderInterface *iface;
+
+    g_return_val_if_fail (NAUTILUS_IS_PROPERTY_PAGE_MODEL_PROVIDER (self), NULL);
+
+    iface = NAUTILUS_PROPERTY_PAGE_MODEL_PROVIDER_GET_IFACE (self);
+
+    g_return_val_if_fail (iface->get_model != NULL, NULL);
+
+    return iface->get_model (self);
+}
+
+void
+nautilus_property_page_model_provider_set_files (NautilusPropertyPageModelProvider *self,
+                                                 GList                             *files)
+{
+    NautilusPropertyPageModelProviderInterface *iface;
+
+    g_return_if_fail (NAUTILUS_IS_PROPERTY_PAGE_MODEL_PROVIDER (self));
+
+    iface = NAUTILUS_PROPERTY_PAGE_MODEL_PROVIDER_GET_IFACE (self);
+
+    g_return_if_fail (iface->set_files != NULL);
+
+    iface->set_files (self, files);
+}
+
+gboolean
+nautilus_property_page_model_provider_supports_files (NautilusPropertyPageModelProvider *self)
+{
+    NautilusPropertyPageModelProviderInterface *iface;
+
+    g_return_val_if_fail (NAUTILUS_IS_PROPERTY_PAGE_MODEL_PROVIDER (self), FALSE);
+
+    iface = NAUTILUS_PROPERTY_PAGE_MODEL_PROVIDER_GET_IFACE (self);
+
+    g_return_val_if_fail (iface->supports_files != NULL, FALSE);
+
+    return iface->supports_files (self);
+}