Gtk.TreeModelFilter.prototype.set_modify_func

function set_modify_func(types:[GType], func:Gtk.TreeModelFilterModifyFunc):void {
    // Gjs wrapper for gtk_tree_model_filter_set_modify_func()
}

With the n_columns and types parameters, you give an array of column types for this model (which will be exposed to the parent model/view). The func, data and destroy parameters are for specifying the modify function. The modify function will get called for <emphasis>each</emphasis> data access, the goal of the modify function is to return the data which should be displayed at the location specified using the parameters of the modify function.

Since 2.4