[gnome-session] [capplet] Make the treeview a drag source

[Vincent Untz <vuntz src gnome org>]

commit 29205aec38469c54a099552f82b3932a15b3d039
Author: Vincent Untz <vuntz gnome org>
Date:   Wed Jun 24 00:48:23 2009 +0200

    [capplet] Make the treeview a drag source
    
    Note that we explicitly forbid dropping drags from the treeview itself
    since it doesn't make sense.
    
    This required a new GspApp API (gsp_app_get_path()).
    Also on_drag_data() was renamed to on_drag_data_received().

 capplet/gsm-properties-dialog.c |  101 ++++++++++++++++++++++++++++++++++-----
 capplet/gsp-app.c               |    8 +++
 capplet/gsp-app.h               |    1 +
 3 files changed, 98 insertions(+), 12 deletions(-)
---
diff --git a/capplet/gsm-properties-dialog.c b/capplet/gsm-properties-dialog.c
index 2ef1314..b0526b2 100644
--- a/capplet/gsm-properties-dialog.c
+++ b/capplet/gsm-properties-dialog.c
@@ -271,14 +271,14 @@ on_startup_enabled_toggled (GtkCellRendererToggle *cell_renderer,
 }
 
 static void
-on_drag_data (GtkWidget           *widget,
-              GdkDragContext      *drag_context,
-              gint                 x,
-              gint                 y,
-              GtkSelectionData    *data,
-              guint                info,
-              guint                time,
-              GsmPropertiesDialog *dialog)
+on_drag_data_received (GtkWidget           *widget,
+                       GdkDragContext      *drag_context,
+                       gint                 x,
+                       gint                 y,
+                       GtkSelectionData    *data,
+                       guint                info,
+                       guint                time,
+                       GsmPropertiesDialog *dialog)
 {
         gboolean dnd_success;
 
@@ -301,7 +301,59 @@ on_drag_data (GtkWidget           *widget,
         }
 
         gtk_drag_finish (drag_context, dnd_success, FALSE, time);
-        g_signal_stop_emission_by_name (widget, "drag-data-received");
+        g_signal_stop_emission_by_name (widget, "drag_data_received");
+}
+
+static void
+on_drag_begin (GtkWidget           *widget,
+               GdkDragContext      *context,
+               GsmPropertiesDialog *dialog)
+{
+        GtkTreePath *path;
+        GtkTreeIter  iter;
+        GspApp      *app;
+
+        gtk_tree_view_get_cursor (GTK_TREE_VIEW (widget), &path, NULL);
+        gtk_tree_model_get_iter (GTK_TREE_MODEL (dialog->priv->tree_filter),
+                                 &iter, path);
+        gtk_tree_path_free (path);
+
+        gtk_tree_model_get (GTK_TREE_MODEL (dialog->priv->tree_filter),
+                            &iter,
+                            STORE_COL_APP, &app,
+                            -1);
+
+        if (app) {
+                g_object_set_data_full (G_OBJECT (context), "gsp-app",
+                                        g_object_ref (app), g_object_unref);
+                g_object_unref (app);
+        }
+
+}
+
+static void
+on_drag_data_get (GtkWidget           *widget,
+                  GdkDragContext      *context,
+                  GtkSelectionData    *selection_data,
+                  guint                info,
+                  guint                time,
+                  GsmPropertiesDialog *dialog)
+{
+        GspApp *app;
+
+        app = g_object_get_data (G_OBJECT (context), "gsp-app");
+        if (app) {
+                const char *uris[2];
+                char       *uri;
+
+                uri = g_filename_to_uri (gsp_app_get_path (app), NULL, NULL);
+
+                uris[0] = uri;
+                uris[1] = NULL;
+                gtk_selection_data_set_uris (selection_data, (char **) uris);
+
+                g_free (uri);
+        }
 }
 
 static void
@@ -457,6 +509,7 @@ setup_dialog (GsmPropertiesDialog *dialog)
         GtkCellRenderer   *renderer;
         GtkTreeSelection  *selection;
         GConfClient       *client;
+        GtkTargetList     *targetlist;
 
         gtk_dialog_add_buttons (GTK_DIALOG (dialog),
                                 GTK_STOCK_HELP, GTK_RESPONSE_HELP,
@@ -536,15 +589,39 @@ setup_dialog (GsmPropertiesDialog *dialog)
         gtk_tree_view_set_search_column (treeview, STORE_COL_DESCRIPTION);
         gtk_tree_view_set_rules_hint (treeview, TRUE);
 
+        gtk_tree_view_enable_model_drag_source (treeview,
+                                                GDK_BUTTON1_MASK|GDK_BUTTON2_MASK,
+                                                NULL, 0,
+                                                GDK_ACTION_COPY);
+        gtk_drag_source_add_uri_targets (GTK_WIDGET (treeview));
+
         gtk_drag_dest_set (GTK_WIDGET (treeview),
                            GTK_DEST_DEFAULT_ALL,
                            NULL, 0,
                            GDK_ACTION_COPY);
         gtk_drag_dest_add_uri_targets (GTK_WIDGET (treeview));
 
-        g_signal_connect (treeview,
-                          "drag-data-received",
-                          G_CALLBACK (on_drag_data),
+        /* we don't want to accept drags coming from this widget */
+        targetlist = gtk_drag_dest_get_target_list (GTK_WIDGET (treeview));
+        if (targetlist != NULL) {
+                GList *list;
+                list = targetlist->list;
+                while (list != NULL) {
+                        GtkTargetPair *targetpair;
+                        targetpair = list->data;
+                        targetpair->flags = GTK_TARGET_OTHER_WIDGET;
+                        list = list->next;
+                }
+        }
+
+        g_signal_connect (treeview, "drag_begin",
+                          G_CALLBACK (on_drag_begin),
+                          dialog);
+        g_signal_connect (treeview, "drag_data_get",
+                          G_CALLBACK (on_drag_data_get),
+                          dialog);
+        g_signal_connect (treeview, "drag_data_received",
+                          G_CALLBACK (on_drag_data_received),
                           dialog);
 
         gtk_tree_sortable_set_sort_column_id (GTK_TREE_SORTABLE (dialog->priv->list_store),
diff --git a/capplet/gsp-app.c b/capplet/gsp-app.c
index 759430a..77483e0 100644
--- a/capplet/gsp-app.c
+++ b/capplet/gsp-app.c
@@ -511,6 +511,14 @@ gsp_app_get_basename (GspApp *app)
         return app->priv->basename;
 }
 
+const char *
+gsp_app_get_path (GspApp *app)
+{
+        g_return_val_if_fail (GSP_IS_APP (app), NULL);
+
+        return app->priv->path;
+}
+
 gboolean
 gsp_app_get_hidden (GspApp *app)
 {
diff --git a/capplet/gsp-app.h b/capplet/gsp-app.h
index 1a29058..7dce444 100644
--- a/capplet/gsp-app.h
+++ b/capplet/gsp-app.h
@@ -71,6 +71,7 @@ gboolean         gsp_app_copy_desktop_file (const char   *uri);
 void             gsp_app_delete            (GspApp       *app);
 
 const char      *gsp_app_get_basename      (GspApp       *app);
+const char      *gsp_app_get_path          (GspApp       *app);
 
 gboolean         gsp_app_get_hidden        (GspApp       *app);