Ios 单选按钮问题

我正在我的一个项目中使用onegray的单选按钮类。这里提到的是：

我在测验中用这些单选按钮选择答案。当用户单击“下一步”按钮时，标签将填充新选项。唯一的问题是旧的不会消失。因此，当我单击“下一步”时，新的按钮集被放置在旧按钮的顶部

首先检查它们是否已经存在的最简单方法是什么。。如果是的话。。删除它们。。在展示新产品之前

这是我的密码

@interface LABViewControllerQuiz ()

@end

@implementation LABViewControllerQuiz
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}
int  counter =0;
- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    _fileContents = [NSString stringWithContentsOfFile:[[NSBundle mainBundle]pathForResource:@"quizQuestions" ofType:@"txt"] encoding:NSUTF8StringEncoding error: nil];
    _theScanner = [NSScanner scannerWithString:_fileContents];
    _separator = [NSCharacterSet characterSetWithCharactersInString:@"~"];
    _lineBreak =[NSCharacterSet characterSetWithCharactersInString:@"@"];
    _alreadyGeneratedNumbers =[[NSMutableArray alloc]init];
    _numQuestions =0;
    _userAnswers = [[NSMutableArray alloc]init];
    _answerKey = [[NSMutableArray alloc]init];

    [self nextQuestion:nil];

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
 #pragma mark - Navigation

 // In a storyboard-based application, you will often want to do a little preparation before navigation
 - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
 {
 // Get the new view controller using [segue destinationViewController].
 // Pass the selected object to the new view controller.
 }
 */


- (IBAction)nextQuestion:(UIButton *)sender
{
    _NextQuestionButton.enabled = YES;
    _submitButton.enabled = NO;
    NSLog(@"NumQuestion = %d", _numQuestions);
    if (_numQuestions >9)
    {
        _NextQuestionButton.enabled = NO;
        _submitButton.enabled = YES;
    }else
    {
        int r = arc4random() %20;
        while ([_alreadyGeneratedNumbers containsObject:[NSNumber numberWithInt:r]])
        {
            r = arc4random() %20;
        }
        [_alreadyGeneratedNumbers addObject:[NSNumber numberWithInt:r]];


        while(![_theScanner isAtEnd])
        {
            NSLog(@"Location= %d", [_theScanner scanLocation]);
            NSLog(@"Already Generated numbers:");
            int i =0;
            while (i < [_alreadyGeneratedNumbers count])
            {
                NSLog(@"%@", [_alreadyGeneratedNumbers objectAtIndex:i]);
                i++;
            }

            NSString *line;
            _lineArray = [[NSMutableArray alloc] init];
            [_theScanner scanUpToCharactersFromSet:_lineBreak intoString:&line];
            [_theScanner setCharactersToBeSkipped:_lineBreak];
            NSScanner *inner = [NSScanner scannerWithString:line];
            NSString *word;
            int wordCount = 0;
            NSLog(@"r = %d counter = %d", r, counter);
            if (counter ==r)
            {
                while(![inner isAtEnd])
                {
                    [inner scanUpToCharactersFromSet:_separator intoString:&word];
                    [inner setCharactersToBeSkipped:_separator];
                    [_lineArray insertObject:word atIndex:wordCount];
                    _questionText.text = [NSString stringWithFormat:@"Question %d \n %@", _numQuestions +1,[_lineArray objectAtIndex:0]];
                    wordCount++;
                    [_theScanner setScanLocation:0];
                    counter = 0;

                }

                [sender setHidden:YES];
                NSMutableArray* buttons = [NSMutableArray arrayWithCapacity:4];
                CGRect btnRect = CGRectMake(25, 420, 300, 30);
                for (NSString* optionTitle in @[[_lineArray objectAtIndex:1], [_lineArray objectAtIndex:2], [_lineArray objectAtIndex:3], [_lineArray objectAtIndex:4]])
                {
                    RadioButton* btn = [[RadioButton alloc] initWithFrame:btnRect];
                    [btn addTarget:self action:@selector(onRadioButtonValueChanged:) forControlEvents:UIControlEventValueChanged];
                    btnRect.origin.y += 40;
                    [btn setTitle:optionTitle forState:UIControlStateNormal];
                    [btn setTitleColor:[UIColor darkGrayColor] forState:UIControlStateNormal];
                    btn.titleLabel.font = [UIFont boldSystemFontOfSize:17];
                    [btn setImage:[UIImage imageNamed:@"unchecked.png"] forState:UIControlStateNormal];
                    [btn setImage:[UIImage imageNamed:@"checked.png"] forState:UIControlStateSelected];
                    btn.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;
                    btn.titleEdgeInsets = UIEdgeInsetsMake(0, 6, 0, 0);
                    [self.view addSubview:btn];
                    [buttons addObject:btn];
                }


                [buttons[0] setGroupButtons:buttons]; // Setting buttons into the group

                [buttons[0] setSelected:NO]; // Making the first button initially selected

                NSLog(@"the question is = %@", [_lineArray objectAtIndex:0]);
                //NSLog(@"Line arrayINDEX %d = %@", wordCount,[_lineArray objectAtIndex:wordCount]);                _numQuestions ++;
                break;
            }else
            {
                counter ++;
            }

        }
    }
    [_answerKey addObject:[_lineArray objectAtIndex:5]];

}

-(void) onRadioButtonValueChanged:(RadioButton*)sender
{
    // Lets handle ValueChanged event only for selected button, and ignore for deselected
    if(sender.selected)
    {
        NSLog(@"Selected: %@", sender.titleLabel.text);

    }
}

@interface labviewcontrollerquick（）
@结束
@LabVIEWControllerQuike的实现
-（id）initWithNibName:（NSString*）nibNameOrNil bundle:（NSBundle*）nibBundleOrNil
{
self=[super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]；
如果（自我）{
//自定义初始化
}
回归自我；
}
int计数器=0；
-（无效）viewDidLoad
{
[超级视图下载]；
//加载视图后执行任何其他设置。
_fileContents=[NSString stringWithContentsOfFile:[NSBundle mainBundle]pathForResource:@“txt”类型的“quizQuestions”编码：NSUTF8StringEncoding错误：nil]；
_扫描仪=[NSScanner SCANNER WITHSTRING:_fileContents]；
_分隔符=[NSCharacterSet characterSetWithCharactersInString:@“~”]；
_lineBreak=[NSCharacterSet characterSetWithCharactersInString:@“@”]；
_alreadyGeneratedNumbers=[[NSMutableArray alloc]init]；
_numQuestions=0；
_userAnswers=[[NSMutableArray alloc]init]；
_answerKey=[[NSMutableArray alloc]init]；
[自我下一个问题：无]；
}
-（无效）未收到记忆警告
{
[超级记忆警告]；
//处置所有可以重新创建的资源。
}
/*
#pragma标记-导航
//在基于故事板的应用程序中，您通常需要在导航之前做一些准备
-（void）prepareForSegue:（UIStoryboardSegue*）segue发送方：（id）发送方
{
//使用[segue destinationViewController]获取新的视图控制器。
//将选定对象传递给新的视图控制器。
}
*/
-（iAction）下一个问题：（UIButton*）发送者
{
_NextQuestionButton.enabled=是；
_submitButton.enabled=否；
NSLog（@“NumQuestion=%d”，numQuestions）；
如果（_numQuestions>9）
{
_NextQuestionButton.enabled=否；
_submitButton.enabled=是；
}否则
{
int r=arc4random（）%20；
而（[\u alreadyGeneratedNumbers containsObject:[NSNumber numberWithInt:r]]）
{
r=arc4random（）%20；
}
[\u alreadyGeneratedNumbers添加对象：[NSNumber numberWithInt:r]]；
而（！[[扫描者正在扫描]）
{
NSLog（@“位置=%d”，[\u扫描仪位置]；
NSLog（@“已生成编号：”）；
int i=0；
而（i<[[u已生成的数字计数]）
{
NSLog（@“%@，[\u alreadyGeneratedNumbers对象索引：i]）；
i++；
}
NSString*行；
_lineArray=[[NSMutableArray alloc]init]；
[\u扫描仪扫描字符从集合：\u换行到字符串：&line]；
[\u扫描仪设置字符已禁用：\u lineBreak]；
NSScanner*内部=[NSScanner scannerWithString:line]；
NSString*字；
int字数=0；
NSLog（@“r=%d计数器=%d”，r，计数器）；
如果（计数器==r）
{
而（！[inner Isattend]）
{
[内部扫描字符从集合：_分隔符到字符串：&word]；
[内部设置字符stobeskiped:_分隔符]；
[_linearrayinsertobject:word-atIndex:wordCount]；
_questionText.text=[NSString stringWithFormat:@“问题%d\n%@”，\u numQuestions+1，[\u lineArray objectAtIndex:0]]；
字数++；
[_扫描仪设置扫描位置：0]；
计数器=0；
}
[发件人设置隐藏：是]；
NSMutableArray*按钮=[NSMutableArray阵列容量：4]；
CGRect btnRect=CGRectMake（25420300,30）；
对于（NSString*OPTIONTILE在@[[U lineArray objectAtIndex:1]、[U lineArray objectAtIndex:2]、[U lineArray objectAtIndex:3]、[U lineArray objectAtIndex:4]]
{
RadioButton*btn=[[RadioButton alloc]initWithFrame:btnRect]；
[btn addTarget:self action:@selector（onRadioButtonValueChanged:）for ControlEvents:UIControlEventValueChanged]；
b精确原点y+=40；
[btn setTitle:optionTitle for状态：UIControlStateNormal]；
[btn setTitleColor:[UIColor darkGrayColor]用于状态：UIControlStateNormal]；
btn.titleLabel.font=[UIFont boldSystemFontOfSize:17]；
[btn setImage:[UIImage ImageName:@“unchecked.png”]用于状态：UIControlStateNormal]；
[btn setImage:[UIImage ImageName:@“checked.png”]用于状态：UIControlStateSelected]；
btn.contentHorizontalAlignment=uicontrol内容HorizontalAlignment左侧；
btn.titleEdgeInsets=UIEdgeInsetsMake（0,6,0,0）；
[self.view addSubview:btn]；
[按钮添加对象：btn]；
}
[按钮[0]设置组按钮：按钮]；//将按钮设置到组中
[按钮[0]setSelected:否]；//使第一个按钮最初处于选中状态
NSLog（@“问题是=%@，[\u lineArray objectAtIndex:0]）；
//NSLog（@“Line arrayINDEX%d=%@”，字数，[[u lineArray objectAtIndex:wordCount]）；\u numQuestions++；
打破
}否则
{
计数器++；
}
}
}
[\u answerKey addObject:[\u lineArray objectAtIndex:5]]；
}
-（无效）onRadioButtonValueChanged:（RadioButton*）发送方
{
//仅允许为sele处理ValueChanged事件
@interface LABViewControllerQuiz ()
@property (strong) NSMutableArray *buttons;
@end

NSMutableArray* buttons = [NSMutableArray arrayWithCapacity:4];

if (self.buttons) {
  [self.buttons makeObjectsPerformSelector:@selector(removeFromSuperview)];
  [self.buttons removeAllObjects];
} else {
  self.buttons = [NSMutableArray arrayWithCapacity:4];
}