UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(returnTop)];
self.navigationItem.titleView.userInteractionEnabled = YES;
self.navigationItem.titleView.userInteractionEnabled = YES;
[self.navigationController.navigationBar addGestureRecognizer:tap];
#pragma mark - 回到顶部
- (void)returnTop {
[self.tableView setContentOffset:CGPointMake(0, - 44) animated:YES];
}
- (void)returnTop {
[self.tableView setContentOffset:CGPointMake(0, - 44) animated:YES];
}