It looks like the param spec for interpolate-size was
copied from the line above it, which is a read only property.
There is a setter for interpolate-size, and it is implemented in
set_property().
stack_props[PROP_INTERPOLATE_SIZE] =
g_param_spec_boolean ("interpolate-size", P_("Interpolate size"), P_("Whether or not the size should smoothly change when changing between differently sized children"),
FALSE,
- GTK_PARAM_READABLE);
+ GTK_PARAM_READWRITE);
g_object_class_install_properties (object_class, LAST_PROP, stack_props);