自定义导航栏返回按钮

UIButton *_isussebtn;

    

    

    _isussebtn = [UIButton buttonWithType:UIButtonTypeRoundedRect];

    _isussebtn.frame = CGRectMake(0, 0, 20, 20);

    [_isussebtn setImage:[UIImage imageNamed:@"zuo"] forState:UIControlStateNormal];

    _isussebtn.titleLabel.font = [UIFont systemFontOfSize:18];

    [_isussebtn addTarget:self action:@selector(backbtn) forControlEvents:UIControlEventTouchUpInside];

    //添加到导航条

    UIBarButtonItem *rightitem = [[UIBarButtonItem alloc]initWithCustomView:_isussebtn];

    self.navigationItem.leftBarButtonItem = rightitem;

-(void)backbtn{

    [self.navigationController dismissViewControllerAnimated:YES completion:nil];

}