Custom Button Issue JS

cur_frm.cscript['Get Alternative Items']= function(doc){
      var dialog = new frappe.ui.Dialog({
        title:__('Alternative Items'),
        fields: [
          {fieldtype:'HTML', fieldname:'alt_item_name', label:__(''), reqd:false,
            description: __("")},
            {fieldtype:'Button', fieldname:'get_item_details', label:__('Ok') }
        ]
      })
      var fd = dialog.fields_dict;
      $(fd.get_item_details.input).closest('div').css("padding-top","15px")
        frappe.call({
          method:"erpnext.selling.custom_methods.get_alternative_item_details",
          args:{"doc":cur_frm.doc},
          callback:function(r){
            var me = this;
             var result_set =r.message
             alter_dic={}
             $.each(result_set,function(i,d){
                if (d.length!=0){
                  me.table = $("<br><div><b>Alternative Items for "+i+"</b></div></br><div style='width:100%;height:200px;overflow:scroll'><form><table class='table table-bordered' id='mytable'>\
                      <thead><tr><th></th><th>Item</th><th>Stock Level</th></tr></thead>\
                       <tbody></tbody>\
                       </table></form></div>").appendTo($(fd.alt_item_name.wrapper))
                  $.each(d,function(key,val){
                      var row = $("<tr>").appendTo(me.table.find("tbody"));
                       $("<td>").html('<input type="radio" name="sp" id="'+i+'">')
                          .attr("item", val["item_code"])
                          .attr("qty", val["actual_qty"])
                        .appendTo(row)
                      $("<td>").html('<p>'+val["item_code"]+'</p>').appendTo(row);
                      $("<td>").html('<p>'+val["actual_qty"]+'</p>').appendTo(row);
                  })

                }
                else{
                  $('<div><b>Alternative Items for '+i+'</b></div></br><div><h5>There is no Stock available of any Equivalent Item</h5></div>').appendTo($(fd.alt_item_name.wrapper))
                }
            })
              dialog.show();
              $("input[name='sp']").change(function () {
                    alter_dic[$(this).attr('id')]={"item_code":$(this).closest('td').attr("item"),"qty":$(this).closest('td').attr("qty")}
              })
              $(fd.get_item_details.input).click(function(){
                frappe.call({
                  method: "erpnext.selling.custom_methods.set_alternative_item_details",
                  args: { "alter_dic":alter_dic,"doc":cur_frm.doc},
                  callback: function(r){
                     dialog.hide()
                     refresh_field('delivery_note_details')
                  }
              })

           })

          }
      })
}