Why is my chart extension not responding to Selected Row Changed trigger in thingworx mashup

Hi 

I have created a chart extension configuring the line chart from the custom chart widget extension package v 3.0.3 downloaded from the p t c marketplace. While using the extension the values are being displayed properly but in my chart extension the Selected Row Changed trigger function is not working ie. when I select a point from the chart I need to invoke a service. I had achieved this while using any inbuilt chart like for example a label chart. When I used a label chart I used the selected row changed to invoke a service which I had written.(This was working perfectly as required, I needed some additional features than the inbuilt chart I had to make the extension). But this same functionality(i e. Selected Row Changed) is not working using a extension chart widget.

I would like to know if there is any way I can configure my extension to get triggered by the Selected Row Changed or is it that the Selected Row Changed works only with inbuilt charts like the label chart or time series chart , etc. I am using an info table made using a service to bind the Chart and so it gets triggered using the Selected Row Changed function. But in my extension the point is not being selected in order to make the trigger function unlike the inbuilt charts. Can You Please help to find a solution for this.