Uncaught TypeError: Cannot read property 'start' of undefined

[Prad]

Hi, 

I'm using the Kendo UI Gantt Chart using the declaration from the basic usage on the demo page : http://demos.telerik.com/kendo-ui/gantt/index

 

My Declaration is pretty much a copy and paste from the site with a variation to an end-point that is serving static data, and the ID's have been changed to string to support GUID IDs:

<script src="~/Content/kendoui/js/kendo.all.min.js" type="text/javascript"></script>
    <link rel="stylesheet" href="~/Content/kendoui/styles/kendo.common.min.css"/>
    <link rel="stylesheet" href="~/Content/kendoui/styles/kendo.default.min.css" />
    <link rel="stylesheet" href="~/Content/kendoui/styles/kendo.dataviz.min.css" />
    <link rel="stylesheet" href="~/Content/kendoui/styles/kendo.dataviz.default.min.css" />

    <script>
    $(function () {

        var serviceRoot = "https://localhost:44301";
        var tasksDataSource = new kendo.data.GanttDataSource({
            batch: false,
            transport: {
                read: {
                    url: serviceRoot + "/Project/Tasks?ID=@Model.ID",
                    dataType: "jsonp"
                },
                update: {
                    url: serviceRoot + "/Project/UpdateTasks?ID=@Model.ID",
                    dataType: "jsonp"
                },
                destroy: {
                    url: serviceRoot + "/Project/DestroyTask?ID=@Model.ID",
                    dataType: "jsonp"
                },
                create: {
                    url: serviceRoot + "/Project/CreateTask?ID=@Model.ID",
                    dataType: "jsonp"
                },
                parameterMap: function (options, operation) {
                    if (operation !== "read") {
                        return { models: kendo.stringify(options.models || [options]) };
                    }
                }
            },
            schema: {
                model: {
                    id: "id",
                    fields: {
                        id: { from: "ID", type: "string" },
                        orderId: { from: "OrderID", type: "number", validation: { required: true } },
                        parentId: { from: "ParentID", type: "string", defaultValue: null, validation: { required: true } },
                        start: { from: "Start", type: "date" },
                        end: { from: "End", type: "date" },
                        title: { from: "Title", defaultValue: "", type: "string" },
                        percentComplete: { from: "PercentComplete", type: "number" },
                        summary: { from: "Summary", type: "boolean" },
                        expanded: { from: "Expanded", type: "boolean", defaultValue: true }
                    }
                }
            }
        });

        var dependenciesDataSource = new kendo.data.GanttDependencyDataSource({
            transport: {
                read: {
                    url: serviceRoot + "/Project/Dependencies?ID=@Model.ID",
                dataType: "jsonp"
            },
            update: {
                url: serviceRoot + "/Project/UpdateDependencies?ID=@Model.ID",
            dataType: "jsonp"
        },
            destroy: {
            url: serviceRoot + "/Project/DestroyDependencies?ID=@Model.ID",
                    dataType: "jsonp"
                },
                create: {
                    url: serviceRoot + "/Project/CreateDependency?ID=@Model.ID",
                    dataType: "jsonp"
                },
                parameterMap: function (options, operation) {
                    if (operation !== "read" && options.models) {
                        return { models: kendo.stringify(options.models) };
                    }
                }
            },
            schema: {
                model: {
                    id: "id",
                    fields: {
                        id: { from: "ID", type: "string" },
                        predecessorId: { from: "PredecessorID", type: "string" },
                        successorId: { from: "SuccessorID", type: "string" },
                        type: { from: "Type", type: "number" }
                    }
                }
            }
        });

        var gantt = $("#gantt").kendoGantt({
            dataSource: tasksDataSource,
            dependencies: dependenciesDataSource,
            views: [
                "day",
                { type: "week", selected: true },
                "month"
            ],
            columns: [
                { field: "id", title: "ID", width: 60 },
                { field: "title", title: "Title", editable: true, sortable: true },
                { field: "start", title: "Start Time", format: "{0:dd/MM/yyyy}", width: 100, editable: true, sortable: true },
                { field: "end", title: "End Time", format: "{0:dd/MM/yyyy}", width: 100, editable: true, sortable: true }
            ],
            height: 700,

            showWorkHours: false,
            showWorkDays: false,

            snap: false
        }).data("kendoGantt");

        $(document).bind("kendo:skinChange", function () {
            gantt.refresh();
        });
    });
    </script>

 

 

 

My end point is returning :

Tasks:

{"Data":[],"Total":0,"AggregateResults":null,"Errors":null}

 

Dependency:

{"Data":[],"Total":0,"AggregateResults":null,"Errors":null}

 

Its currently not returning anything since it is empty. 

However, I'm receiving "Uncaught TypeError: Cannot read property 'start' of undefined" on line 52 on kendo.all.min.js:52. I'm not sure what the error is, would you be able to please able to assist ? 

[Bozhidar]

Hello,

I tested the gantt widget with empty results being returned from the service, but I wasn't able to reproduce the error on my end. Could you confirm that you are using the latest version of the scripts? Perhaps it's an old bug that we've already fixed.

Regards,
Bozhidar
Telerik

 

 

[Prad]

Hi, thanks for your reply. Its the latest version I believe, it was downloaded 2 days prior to posting this.

I'm receiving this as well when I press Add Task. Is this the same for you?

[Prad]

Thanks for your assistance, but I've managed to sort it out. 

 

The reason for the error was that I was returning back a JSON and in intialisation I've indicated that it should be JSONP. I changed it to JSON and everything is now working.