Unable to get handleIndex of jQuery Slider on change

Unable to get handleIndex of jQuery Slider on change

Hi, I have slider with 2 handles. I want to get which handle was changed. I see in jQuery documentation that we can use change event and then ui object to get handleIndex. I have seen the examples. They work fine. 

But with my slider, it is not. Here is my slider: 

  1. var slider = $("#slider").slider(
        {
            id: "slider1",
     min: 0,
     max: 40000,
     step: 100,
     value: [${val1}, ${val2}]
        }
    ).on('slide', function ( event, ui ) {
        //    some work here. 
    }).on('change', function ( event, ui ) {

     // This below line does not work for me. 
        // says ui object is undefined
     var index = $(ui.handle).index();
        console.log("ind: " + index);
    })
        .    data('slider');