冒泡排序

NSArray*mallArr = [mallArray sortedArrayUsingComparator:

                           ^NSComparisonResult(XPShoppingMallBO *obj1, XPShoppingMallBO *obj2){

                                NSComparisonResult result = [obj1.distense compare:obj2.distense];

                                if (result== NSOrderedSame) {

                                   result = [obj1.distensecompare:obj2.distense];

                               }

                                return result;

                           }];