code: function(value) {
          var me = this,
              record;
  
          me.value = value;
  
          if (me.store.loading) {
              // Called while the Store is loading. Ensure it is processed by the onLoad method.
              return me;
          }
              
          // try to find a record in the store that matches the value
          record = value ? me.store.getNodeById(value) : me.store.getRootNode();
          if (value === undefined) {
              record = me.store.getRootNode();
              me.value = record.getId();
          } else {
              record = me.store.getNodeById(value);
          }
  
          // set the raw value to the record's display field if a record was found
          me.setRawValue(record ? record.get(me.displayField) : '');
  
          return me;
      }
docs: Sets the specified value into the field
  @param {Mixed} value
  @return {Ext.ux.TreePicker} this