Trying to update a tree row with

treerow[idx] = None

fails like:

TypeError: Argument 3 does not allow None as a value

This convenience syntax maps to gtk_tree_store_set_value, so I tried the obvious:

diff --git a/gtk/gtktreestore.c b/gtk/gtktreestore.c
index 21e7a20..9830caf 100644
--- a/gtk/gtktreestore.c
+++ b/gtk/gtktreestore.c
@@ -937,7 +937,7 @@ gtk_tree_store_real_set_value (GtkTreeStore *tree_store,
  * @tree_store: a #GtkTreeStore
  * @iter: A valid #GtkTreeIter for the row being modified
  * @column: column number to modify
- * @value: new value for the cell
+ * @value: (allow-none): new value for the cell
  *
  * Sets the data in the cell specified by @iter and @column.
  * The type of @value must be convertible to the type of the


However that hits an assertion since it requires a gtk value.

All this worked with pygtk2 bindings. My usecase is a tooltip column: setting it to an empty string still shows an empty tooltip, so you want to be able to set None. Appending a row to a treestore doesn't complain about any None values.

Maybe this is entirely a gtk issue but since there seems to be some magic glue here I figured I'd try here first, please reassign if necessary.