-(NSArray *)roles{    if (_roles == nil) {
　　　　　//获取数据文件        NSString       *path         = [[NSBundle mainBundle]pathForResource:@"heros.plist" ofType:nil];        NSArray        *array        = [NSArray arrayWithContentsOfFile:path];        NSMutableArray *mutableArray = [NSMutableArray array];        //取数据        for (NSDictionary *dic in array) {            RoleEntity * role = [RoleEntity roleWithDictionary:dic];            [mutableArray addObject:role];        }        _roles = mutableArray;    }    return  _roles;}