Combine new filters with active filters

[Tim]

Hello,

I'm using a multiselect filter for the one of my columns. Also I want to maintain the active filters so you can further narrow down the result.
For now i'm trying to do this as below but the OldFilters variable is empty.

                    function areaOfStudyFilter(element)
        {
            //mvvm binding should be removed, other way the dataSource will try to update the UI when the dataSource filter has changed
            element.removeAttr("data-bind");
            var dataSource = $("#Grid").data("kendoGrid").dataSource
            element.kendoMultiSelect({
                optionLabel: "-Selecteer waarde-",
                dataSource:
                    {
                        transport: {
                            read: "@Url.Action("Filter_AreaOfStudyDescriptions")"
                        }
                    },
                change: function (e) {
                    var oldFilters = dataSource.filter();
                    var filter = {logic:"and", filters:[]}
                    var newFilter = { logic: "or", filters: [] };
                    var values = this.value();
                    if (values.length == 0)
                    {
                        dataSource.filter({ field: "AreaOfStudy", operator: "startswith", value: "" })
                        oldFilters = dataSource.filter();
                    }

                    $.each(values, function (i, v) {
                        newFilter.filters.push({ field: "AreaOfStudy", operator: "eq", value: v });
                        dataSource.filter({ field: "AreaOfStudy", operator: "startswith", value: "" })
                        oldFilters = dataSource.filter();
                    });
                    filter.filters.push(newFilter);
                    filter.filters.push(oldFilters);
                    dataSource.filter(filter);
                }
            });
        }

Kind Regards,

Tim

[Kiril Nikolov]

Hello Tim,

From the provided code sample I am not able to tell you exactly what is causing this behavior. Would it be possible to provide a runnable sample that we can debug and see what exactly happens? 

Thank you in advance for this.

Regards,
Kiril Nikolov
Telerik