自定义tabBar

UIBarButtonItem *reFresh = [[UIBarButtonItem alloc]initWithImage:[[UIImage imageNamed:@"iconfont-shuaxin"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] style:UIBarButtonItemStyleDone target:self action:@selector(reFreshAction)];

self.navigationItem.rightBarButtonItem = reFresh;