How to get Index of selected option from drop-down option list dynamically?

I have a richSelect dorp down view. On selction of any option, I need the index of that selected option from OptionList array.

You need to reach the list object withgetList() method and then get the index via ID:

  view:"richselect",
  on:{
    onChange:function(newV){
      var id = this.getList().getIndexById(newV)
    }
  }

Thanks. It really helps.