Sets the function used for filtering items.
If match_func is null, the filter matches all items.
If the filter func changes its filtering behavior, gtk.filter.Filter.changed needs to be called.
If a previous function was set, its user_destroy will be called now.
function to filter items
Sets the function used for filtering items.
If match_func is null, the filter matches all items.
If the filter func changes its filtering behavior, gtk.filter.Filter.changed needs to be called.
If a previous function was set, its user_destroy will be called now.