title: ExtJS Grid JSON Store Proxy Error
body: <p>I am working on displaying a ExtJS Grid. I got everything correct except the part about proxy with in the Json store. When I try to display it throws an error:</p>
  
  <pre>
  this.proxy is undefined
  Ext.data.Store=function(A){this.data=n...ta=C;this.resumeEvents();return B}});
  </pre>
  
  <p>I figured out that i need to do something in the store but not sure what. the variable list data has the Json Array string. Please any help is really appreciated. thanks</p>
  
  <pre><code>var listData = &lt;%= aItems %&gt; ;
  var AIGrid;
  
  Ext.onReady(function () {
      var AIRecord = Ext.data.Record.create([{
          name: "ID",
          type: "int",
          mapping: "ID"
      }, {
          name: "WSTITLE",
          type: "string",
          mapping: "WSTITLE"
      }, {
          name: "REQ_ATTUID",
          type: "string",
          mapping: "REQ_ATTUID"
      }, {
          name: "DESCRIPTION",
          type: "string",
          mapping: "DESCRIPTION"
      }, {
          name: "RES_ATTUID",
          type: "string",
          mapping: "RES_ATTUID"
      }, {
          name: "RESOLUTION",
          type: "string",
          mapping: "RESOLUTION"
      }, {
          name: "START_TIME",
          type: "string",
          mapping: "START_TIME"
      }, {
          name: "END_TIME",
          type: "string",
          mapping: "END_TIME"
      }]);
  
      var AIreader = new Ext.data.JsonReader({
          root: "root",
          id: "ID"
      }, AIRecord);
  
      var AIstore = new Ext.data.Store({
          nocache: true,
          data: listData,
          reader: AIreader
      });
  
      var AIcol = new Ext.grid.ColumnModel([{
          header: 'ID',
          readOnly: true,
          dataIndex: 'ID',
          width: 30
      }, {
          header: 'Work Step',
          dataIndex: 'WSTITLE',
          width: 200,
          readOnly: true
      }, {
          header: 'Requester',
          dataIndex: 'REQ_ATTUID',
          width: 80,
          readOnly: true
      }, {
          header: 'Description',
          dataIndex: 'DESCRIPTION',
          width: 300,
          readOnly: true
      }, {
          header: 'Resolver',
          dataIndex: 'RES_ATTUID',
          width: 80,
          readOnly: true
      }, {
          header: 'Resolution',
          dataIndex: 'RESOLUTION',
          width: 300,
          readOnly: true
      }, {
          header: 'Start',
          dataIndex: 'START_TIME',
          width: 100,
          readOnly: true
      }, {
          header: 'End',
          dataIndex: 'END_TIME',
          width: 100,
          readOnly: true
      }]);
  
      AIcol.defaultSortable = true;
  
      AIGrid = new Ext.grid.GridPanel({
          store: AIstore,
          renderTo: 'listgrid',
          cm: AIcol,
          enableColLock: true,
          title: 'Open Action Items',
          width: 900,
          height: 500,
          selModel: new Ext.grid.RowSelectionModel({
              singleSelect: true
          })
      });
  
      AIGrid.store.load();
  
  });
  </code></pre>