Setting custom template on column chart results in NullReferenceException on template fields

[Dennis]

Hi!

KendoUI is fantastic, however one problem. I am trying to set a custom template on a column chart for its tooltip, however it seems to be unable to find the fields specified.

Datasource:

var usageData = @Html.Raw(@ServiceStack.Text.JsonSerializer.SerializeToString(Model.ParkingStats));

Code:

$('#chart-utilization').kendoChart({ 

    title: {

        text: "Parking utilization for week"

    },

    dataSource:{

        data: usageData[0].Usage

    },

    series:[{

        type: "column",

        field: "Max",

        name: "Max utilization"

    }],

    categoryAxis:{

        field: "Week"

    },

    tooltip: {

        visible: true,

        template: "${ Max } of ${ Capacity }"

    },

    legend: {

        visible: false

    }

});

The 'Max' and when changed 'Capacity' renders correct columns. But the template can't find either fields and throws a NullReferenceException.


Thanks in advance for your pro-tips ;-) !

Finest regards.

[Dennis]

The JSFiddle: http://jsfiddle.net/3fW95/2/ 

[Alexander Valchev]

Hello Dennis,

Tooltip templates work with predefined variables. More information and example can be found in corresponding documentation.
In your case, try to change the template property to:

template: "#= value # of #= category #"

I hope this will solve your problem.


Regards,
Alexander Valchev
the Telerik team

[Dennis]

Thanks again!
     template: "${value} of ${dataItem.Capacity}"

Works, is there a reason for using #= value # ?
Just for reference and other people, the working JSFiddle: http://jsfiddle.net/3fW95/6/ 

ps. After all your help today, I am confident about the support you guys deliver and will buy a license directly after finishing this post!

[Alexander Valchev]

Hi Dennis,

Thank you for the nice words.

You could use whichever syntax you prefer. In the newest version of the framework we introduced #: # for conformance with #= #. ${} was kept for compatibility, but both of them do the same job.

Kind regards,
Alexander Valchev
the Telerik team

[Dennis]

Hi!

Any rational behind the newly introduced way? I'd like to use the best practise, but not sure if there is one.

[Alexander Valchev]

Hi Dennis,

You should use the one that best fits to your requirements.
${} can be also used for HTML encoding in templates as shown in this examples.

Kind regards,
Alexander Valchev
the Telerik team