iOS 单选按钮组--只能而且必选一个按钮

**1、定于两个属性按钮**
@property (nonatomic, strong) UIButton * sinaButton;
@property (nonatomic, strong) UIButton * bankButton;

self.sinaButton = [UIButton buttonWithType:(UIButtonTypeCustom)];
_sinaButton.frame = CGRectMake(30, 200, 15, 15);
[_sinaButton setBackgroundImage:[UIImage imageNamed:@"invest_delecte"] forState:(UIControlStateNormal)];
[_sinaButton setBackgroundImage:[UIImage imageNamed:@"invest_selecte"] forState:(UIControlStateSelected)];
[_sinaButton addTarget:self action:@selector(sinaAction:) forControlEvents:(UIControlEventTouchUpInside)];
[self.view addSubview:_sinaButton];


UIButton *sinaNme = [UIButton buttonWithType:(UIButtonTypeCustom)];
sinaNme.frame = CGRectMake(_sinaButton.right + 5, _sinaButton.top - 5, 100, 30);
[sinaNme setTitle:@"支付宝"  forState:(UIControlStateNormal)];
[sinaNme setTitleColor:[UIColor blackColor] forState:(UIControlStateNormal)];
[sinaNme addTarget:self action:@selector(sinaAction:) forControlEvents:(UIControlEventTouchUpInside)];
[self.view addSubview:sinaNme];



self.bankButton = [UIButton buttonWithType:(UIButtonTypeCustom)];
_bankButton.frame = CGRectMake(_sinaButton.left, _sinaButton.bottom + 20, _sinaButton.width, _sinaButton.height);
[_bankButton setBackgroundImage:[UIImage imageNamed:@"invest_delecte"] forState:(UIControlStateNormal)];
[_bankButton setBackgroundImage:[UIImage imageNamed:@"invest_selecte"] forState:(UIControlStateSelected)];
[_bankButton addTarget:self action:@selector(bankAction:) forControlEvents:(UIControlEventTouchUpInside)];
[self.view addSubview:_bankButton];


UIButton *banknameSelete = [UIButton buttonWithType:(UIButtonTypeCustom)];
banknameSelete.frame = CGRectMake(sinaNme.left , _bankButton.top - 5, 80, 30);
[banknameSelete setTitle:@"银行卡" forState:(UIControlStateNormal)];
[banknameSelete setTitleColor:[UIColor blackColor] forState:(UIControlStateNormal)];
[banknameSelete addTarget:self action:@selector(bankAction:) forControlEvents:(UIControlEventTouchUpInside)];
[self.view addSubview:banknameSelete];


// 先默认一个选项
 _sinaButton.selected = YES;

- (void)sinaAction:(UIButton *)button
{
      if (_sinaButton.selected) {
     
     }
   else if (!_sinaButton.selected)
   {
       _sinaButton.selected = YES;
       _bankButton.selected = NO;
   }
     NSLog(@"支付宝");
}

- (void)bankAction:(UIButton *)button
{

    if (_bankButton.selected) {
 
     }
    else if (!_bankButton.selected)
    {
     _bankButton.selected = YES;
    _sinaButton.selected = NO;
    }
     NSLog(@"银行卡");
}