[file-roller] Add Files: disable the Add action if no file is selected

[Paolo Bacchilega <paobac src gnome org>]

commit 8bb906223ec9498642b96187f24fc7ec6e613cef
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Wed Jul 3 09:02:46 2013 +0200

    Add Files: disable the Add action if no file is selected
    
    Based on a patch written by Srinivasa Ragavan
    
    [bug #703187]

 src/fr-file-selector-dialog.c |   37 +++++++++++++++++++++++++++++++++++++
 1 files changed, 37 insertions(+), 0 deletions(-)
---
diff --git a/src/fr-file-selector-dialog.c b/src/fr-file-selector-dialog.c
index 8b3fcfc..0e91842 100644
--- a/src/fr-file-selector-dialog.c
+++ b/src/fr-file-selector-dialog.c
@@ -442,6 +442,40 @@ files_modified_column_sort_func (GtkTreeModel *model,
 }
 
 
+static gboolean
+_fr_file_selector_dialog_is_file_selected (FrFileSelectorDialog *self)
+{
+       GtkListStore *list_store;
+       GtkTreeIter   iter;
+
+       list_store = GTK_LIST_STORE (GET_WIDGET ("files_liststore"));
+       if (! gtk_tree_model_get_iter_first (GTK_TREE_MODEL (list_store), &iter))
+               return FALSE;
+
+       do {
+               gboolean is_selected;
+
+               gtk_tree_model_get (GTK_TREE_MODEL (list_store), &iter,
+                                   FILE_LIST_COLUMN_IS_SELECTED, &is_selected,
+                                   -1);
+               if (is_selected)
+                       return TRUE;
+       }
+       while (gtk_tree_model_iter_next (GTK_TREE_MODEL (list_store), &iter));
+
+       return FALSE;
+}
+
+
+static void
+_update_sensitivity (FrFileSelectorDialog *self)
+{
+       gtk_dialog_set_response_sensitive (GTK_DIALOG (self),
+                                          GTK_RESPONSE_OK,
+                                          _fr_file_selector_dialog_is_file_selected (self));
+}
+
+
 static void
 is_selected_cellrenderertoggle_toggled_cb (GtkCellRendererToggle *cell_renderer,
                                           gchar                 *path,
@@ -468,6 +502,8 @@ is_selected_cellrenderertoggle_toggled_cb (GtkCellRendererToggle *cell_renderer,
                            FILE_LIST_COLUMN_IS_SELECTED, ! is_selected,
                            -1);
 
+       _update_sensitivity (self);
+
        gtk_tree_path_free (tree_path);
 }
 
@@ -899,6 +935,7 @@ _set_current_folder (FrFileSelectorDialog *self,
                g_cancellable_cancel (self->priv->current_operation->cancellable);
 
        gtk_list_store_clear (GTK_LIST_STORE (GET_WIDGET ("files_liststore")));
+       _update_sensitivity (self);
 
        self->priv->current_operation = load_data_new (self, folder);
        self->priv->current_operation->files_to_select = _g_object_list_ref (files);