IOS第四天(4:下一题和选框的实现)

#import "HMViewController.h"
#import "HMQuestion.h"

#define kButtonWidth    35
#define kButtonHeight   35
#define kButtonMargin   10
#define kTotolCol       7

@interface HMViewController ()
@property (weak, nonatomic) IBOutlet UIButton *iconButton;
@property (weak, nonatomic) IBOutlet UILabel *noLabel;
@property (weak, nonatomic) IBOutlet UILabel *titleLabel;
@property (weak, nonatomic) IBOutlet UIButton *nextQuestionButton;

@property (weak, nonatomic) IBOutlet UIView *answerView;//答案框
@property (weak, nonatomic) IBOutlet UIView *optionsView;//选择框
@property (nonatomic, strong) NSArray *questions;  //数据

/** 题目索引 */
@property (nonatomic, assign) int index;
@end

@implementation HMViewController

- (NSArray *)questions
{
    if (_questions == nil) {
        _questions = [HMQuestion questions];
    }
    return _questions;
}

- (UIButton *)cover
{
    if (_cover == nil) {
        _cover = [[UIButton alloc] initWithFrame:self.view.bounds];
        _cover.backgroundColor = [UIColor colorWithWhite:0.0 alpha:0.5];
        [self.view addSubview:_cover];
        _cover.alpha = 0.0;
        
        [_cover addTarget:self action:@selector(bigImage) forControlEvents:UIControlEventTouchUpInside];
    }
    return _cover;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.index = -1;
    [self nextQuestion];
}

/** 调整状态栏颜色 */
/**
 UIStatusBarStyleDefault      黑色状态栏
 UIStatusBarStyleLightContent 亮色状态栏
 */
- (UIStatusBarStyle)preferredStatusBarStyle
{
    return UIStatusBarStyleLightContent;
}

 
#pragma mark - 下一题
- (IBAction)nextQuestion
{
    // 1. 当前答题的索引，索引递增
    self.index++;
    
    // 2. 从数组中按照索引取出题目模型数据
    HMQuestion *question = self.questions[self.index];
    
    // 3. 设置基本信息
    self.noLabel.text = [NSString stringWithFormat:@"%d/%d", self.index + 1, self.questions.count];
    self.titleLabel.text = question.title;
    [self.iconButton setImage:[UIImage imageNamed:question.icon] forState:UIControlStateNormal];
    
    // 如果到达最后一题，禁用下一题按钮
    self.nextQuestionButton.enabled = (self.index < self.questions.count - 1);
    
    // 4. 设置答案按钮
    
    // 首先清除掉答题区内的所有按钮
    // 所有的控件都继承自UIView，多态的应用
    for (UIView *btn in self.answerView.subviews) {
        [btn removeFromSuperview];
    }
    
    CGFloat answerW = self.answerView.bounds.size.width;
    int length = question.answer.length;
    CGFloat answerX = (answerW - kButtonWidth * length - kButtonMargin * (length - 1)) * 0.5;
    
    // 创建所有答案的按钮
    for (int i = 0; i < length; i++) {
        CGFloat x = answerX + i * (kButtonMargin + kButtonWidth);
        
        UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(x, 0, kButtonWidth, kButtonHeight)];
        [btn setBackgroundImage:[UIImage imageNamed:@"btn_answer"] forState:UIControlStateNormal];
        [btn setBackgroundImage:[UIImage imageNamed:@"btn_answer_highlighted"] forState:UIControlStateHighlighted];
        
        [self.answerView addSubview:btn];
    }
    
    // 5. 设置备选按钮
    for (UIView *view in self.optionsView.subviews) {
        [view removeFromSuperview];
    }
    
    CGFloat optionW = self.optionsView.bounds.size.width;
    CGFloat optionX = (optionW - kTotolCol * kButtonWidth - (kTotolCol - 1) * kButtonMargin) * 0.5;
    
    for (int i = 0; i < question.options.count; i++) {
        int row = i / kTotolCol;
        int col = i % kTotolCol;
        
        CGFloat x = optionX + col * (kButtonMargin + kButtonWidth);
        CGFloat y = row * (kButtonMargin + kButtonHeight);
        
        UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(x, y, kButtonWidth, kButtonHeight)];
        [btn setBackgroundImage:[UIImage imageNamed:@"btn_option"] forState:UIControlStateNormal];
        [btn setBackgroundImage:[UIImage imageNamed:@"btn_option_highlighted"] forState:UIControlStateHighlighted];
        
        // 设置备选答案
        [btn setTitle:question.options[i] forState:UIControlStateNormal];
        [btn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
        
        [self.optionsView addSubview:btn];
    }
    
    NSLog(@"%d", self.optionsView.subviews.count);
}

@end