sapui5 List SearchField not working

Hi All,

I have a splitApp control in my sapui5 application. I am trying to search the list in master page.

Inside Controller

------------------------

PR_Search: function(oEvent)

{

      var tpmla = oEvent.getParameter("newValue");    

     var filters = new Array();

     var oFilter = new sap.ui.model.Filter("PoNumber",sap.ui.model.FilterOperator.Contains, tpmla);

      filters.push(oFilter);

     //get list created in view

     this.oList =sap.ui.getCore().byId("polist");

     this.oList.getBinding("items").filter(filters);

    },

Inside  view

------------------

new sap.m.SearchField(

{

placeholder: "Search",

showRefreshButton: true,

liveChange : oController.PR_Search,

search: oController.PR_Search,

tooltip: "Search for objects..",

    })

var po_list  = new sap.m.List("polist",{

inset : false,

});

po_list.bindItems({

path : "/HeaderSet",

template : V_List_itemtemplate,

});

I have implemented the code. But the search is not working. Please help in resolving this issue.

Thanks,

Divya