code: function(rec){
          var me          = this,
              node        = me.getNode(rec, true),
              el          = me.el,
              adjustmentY = 0,
              adjustmentX = 0,
              elRegion    = el.getRegion(),
              nodeRegion;
  
          // Viewable region must not include scrollbars, so use
          // DOM client dimensions
          elRegion.bottom = elRegion.top + el.dom.clientHeight;
          elRegion.right = elRegion.left + el.dom.clientWidth;
          if (node) {
              nodeRegion = Ext.fly(node).getRegion();
              // node is above
              if (nodeRegion.top < elRegion.top) {
                  adjustmentY = nodeRegion.top - elRegion.top;
              // node is below
              } else if (nodeRegion.bottom > elRegion.bottom) {
                  adjustmentY = nodeRegion.bottom - elRegion.bottom;
              }
  
              // node is left
              if (nodeRegion.left < elRegion.left) {
                  adjustmentX = nodeRegion.left - elRegion.left;
              // node is right
              } else if (nodeRegion.right > elRegion.right) {
                  adjustmentX = nodeRegion.right - elRegion.right;
              }
  
              if (adjustmentX || adjustmentY) {
                  me.scrollBy(adjustmentX, adjustmentY, false);
              }
              el.focus();
          }
      }
docs: Focuses a node in the view.
  @param {Ext.data.Model} rec The record associated to the node that is to be focused.