Pickers应用程序

一、效果

1. 程序启动进入日期选取器界面，点击按钮显示所选的日期

2. 点击底下工具栏Single,进入单滚轮选取器，点击按钮提示所选信息

3. 点击底下工具栏Double，进入双滚轮选取器，两滚轮各自独立互不影响。点击按钮，提示所选信息

4. 点击底下工具栏Dependent,进入双滚轮选取器，其中第个滚轮随第一个滚轮的变化而变化。点击按钮提示所选信息

5. 点击底下工具栏Custom,进入自定义选取器。点击按钮，随机产生5张图片，只要有相连的3张图片，就胜利

二、分析

1. 根控制器是一个UITabBarController，控制5个UIViewController之间的切换

2. 在各个控制器的View上面拉选取器控件，设定数据源与委托对象

3. 在各个控制器上实现选取器内容的展现

三、 实现

1. Main.storyboard布局

2. 文件

3. 属性列表文件

4. 由于是用storyboard实现的控件布局，所以并不用在主控制器上做什么，其中布局跳转都已经在storyboard里面完成了，现在主要是配置子控制器实现文件

5. DatePickerViewController.m

//
//  DatePickerViewController.m
//  7.1-创建Pickers应用程序
//
//  Created by LinKun on 16/7/16.
//  Copyright © 2016年 Apress. All rights reserved.
//

#import "DatePickerViewController.h"

@interface DatePickerViewController ()
/** 日期选取器 */
@property (weak, nonatomic) IBOutlet UIDatePicker *datePicker;

@end

@implementation DatePickerViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
}

#pragma mark - 提示当前日期选取器所选日期
- (IBAction)buttonPressed:(UIButton *)sender {
    // 提取选取器日期
    NSDate *date = self.datePicker.date;
    
    // 警告信息
    NSString *message = [NSString stringWithFormat:@"The date and time you selected is %@", date];
    // 创建警告框
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Date and Time Selected" message:message preferredStyle:UIAlertControllerStyleAlert];
    UIAlertAction *action = [UIAlertAction actionWithTitle:@"That's true" style:UIAlertActionStyleDefault handler:nil];
    [alert addAction:action];
    [self presentViewController:alert animated:YES completion:nil];
}

@end

6. SingleComponentPickerViewController.m

//
//  SingleComponentPickerViewController.m
//  7.1-创建Pickers应用程序
//
//  Created by LinKun on 16/7/16.
//  Copyright © 2016年 Apress. All rights reserved.
//

#import "SingleComponentPickerViewController.h"

#pragma mark 遵循选取器的数据源、委托方法
@interface SingleComponentPickerViewController () <UIPickerViewDelegate, UIPickerViewDataSource>
/** 单轮选取器 */
@property (weak, nonatomic) IBOutlet UIPickerView *singlePicker;
/** 人物姓名 */
@property (strong, nonatomic) NSArray *characterNames;

@end

@implementation SingleComponentPickerViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    // 加载数据
    self.characterNames = @[@"Xiaoming", @"Maike", @"Qiongsi", @"Jieke", @"Jane", @"Aha"];
    
}

#pragma mark - 提示当前单轮选取器所选的内容
- (IBAction)SingleButton:(id)sender {
    // 所选行索引
    NSInteger row = [self.singlePicker selectedRowInComponent:0];
    // 根据行索引找到对应行数据
    NSString *selected = self.characterNames[row];
    // 警告框标题
    NSString *title = [NSString stringWithFormat:@"You sellected %@", selected];
    
    // 创建警告框
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:title message:@"Thank you for choosing." preferredStyle:UIAlertControllerStyleAlert];
    // 警告按钮
    UIAlertAction *action = [UIAlertAction actionWithTitle:@"You're welcome" style:UIAlertActionStyleDefault handler:nil];
    
    [alert addAction:action];
    [self presentViewController:alert animated:YES completion:nil];
    
}

#pragma mark - 选取器数据源
#pragma mark 多少个滚轮
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
    return 1;
}
#pragma mark 各个滚轮有多少行
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
    return [self.characterNames count];
}

#pragma mark 选取器委托
#pragma mark 选取器滚轮的行标题
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
    return self.characterNames[row];
}


@end

7. DoubleComponentPickerViewController.m

//
//  DoubleComponentPickerViewController.m
//  7.1-创建Pickers应用程序
//
//  Created by LinKun on 16/7/16.
//  Copyright © 2016年 Apress. All rights reserved.
//

#import "DoubleComponentPickerViewController.h"

#pragma mark 滚轮的索引
#define kCoolDrink 0
#define kSize 1

@interface DoubleComponentPickerViewController () <UIPickerViewDataSource, UIPickerViewDelegate>
/** 双滚轮选取器 */
@property (weak, nonatomic) IBOutlet UIPickerView *doublePicker;
// 滚轮数据
@property (strong, nonatomic) NSArray *coolDrinkTypes;
@property (strong, nonatomic) NSArray *sizeTypes;

@end

@implementation DoubleComponentPickerViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    // 加载数据
    self.coolDrinkTypes = @[@"百事", @"可乐", @"雪碧", @"牛奶", @"柠檬汁", @"西瓜汁"];
    self.sizeTypes = @[@"大杯", @"中杯", @"小杯"];
}

#pragma mark - 提示所选信息
- (IBAction)DoubleButton:(UIButton *)sender {
    // 提取各滚轮所选行索引
    NSInteger coolDrinkRow = [self.doublePicker selectedRowInComponent:kCoolDrink];
    NSInteger sizeRow = [self.doublePicker selectedRowInComponent:kSize];
    // 提取行索引对应行数据
    NSString *coolDrink = self.coolDrinkTypes[coolDrinkRow];
    NSString *size = self.sizeTypes[sizeRow];
    // 警告框提示信息
    NSString *message = [NSString stringWithFormat:@"您点的 %@ %@ 马上送到！", coolDrink, size];
    
    // 创建警告框
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Thank you for your order" message:message preferredStyle:UIAlertControllerStyleAlert];
    UIAlertAction *action = [UIAlertAction actionWithTitle:@"Thank you" style:UIAlertActionStyleDefault handler:nil];
    [alert addAction:action];
    [self presentViewController:alert animated:YES completion:nil];
    
    
}

#pragma mark - 选取器数据源
#pragma mark 滚轮数
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
    return 2;
}
#pragma mark 行数
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
    if (component == kCoolDrink) {
        return [self.coolDrinkTypes count];
    } else {
        return [self.sizeTypes count];
    }
}

#pragma mark - 选取器委托
#pragma mark 行标题
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
    if (component == kCoolDrink) {
        return self.coolDrinkTypes[row];
    } else {
        return self.sizeTypes[row];
    }
}



@end

8. DependentComponentPickerViewController.m

//
//  DependentComponentPickerViewController.m
//  7.1-创建Pickers应用程序
//
//  Created by LinKun on 16/7/16.
//  Copyright © 2016年 Apress. All rights reserved.
//

#import "DependentComponentPickerViewController.h"

#define kStateComponent 0
#define kZipComponent 1

@interface DependentComponentPickerViewController () <UIPickerViewDelegate, UIPickerViewDataSource>
/** 依赖性滚轮 */
@property (weak, nonatomic) IBOutlet UIPickerView *dependentPicker;

// 滚轮数据
@property (strong, nonatomic) NSDictionary *stateZips;
/** 州名 */
@property (strong, nonatomic) NSArray *states;
/** 邮编 */
@property (strong, nonatomic) NSArray *zips;

@end

@implementation DependentComponentPickerViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    // 获得应用资源包的引用并提取相应文件的资源路径
    NSBundle *bundle = [NSBundle mainBundle];
    NSURL *plistURL = [bundle URLForResource:@"statedictionary" withExtension:@"plist"];
    // 从资源文件导出数据
    self.stateZips = [NSDictionary dictionaryWithContentsOfURL:plistURL];
    // 字典所有键,按字母顺序排列
    NSArray *allStates = [self.stateZips allKeys];
    NSArray *sortedStates = [allStates sortedArrayUsingSelector:@selector(compare:)];
    self.states = sortedStates;
    
    NSString *selectedState = self.states[0];
    self.zips = self.stateZips[selectedState];
}

- (IBAction)selected:(UIButton *)sender {
    // 提取当前滚轮所选的数据
    NSInteger stateRow = [self.dependentPicker selectedRowInComponent:kStateComponent];
    NSInteger zipRow = [self.dependentPicker selectedRowInComponent:kZipComponent];
    NSString *state = self.states[stateRow];
    NSString *zip = self.zips[zipRow];
    // 警告框标题、警告信息
    NSString *title = [NSString stringWithFormat:@"You selected zip code %@.", zip];
    NSString *message = [NSString stringWithFormat:@"%@ is in %@", zip, state];
    
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
    
    UIAlertAction *action = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil];
    [alert addAction:action];
    [self presentViewController:alert animated:YES completion:nil];
    
}

#pragma mark -
#pragma mark 选取器数据源
#pragma mark 滚轮数
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
    return 2;
}
#pragma mark 行数
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
    if (component == kStateComponent) {
        return [self.states count];
    } else {
        return [self.zips count];
    }
}

#pragma mark - 选取器委托
#pragma mark 行标题
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
    if (component == kStateComponent) {
        return self.states[row];
    } else {
        return self.zips[row];
    }
}
#pragma mark 滚轮数据改变
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
    if (component == kStateComponent) {
        // 州
        NSString *selectedState = self.states[row];
        // 州对应的邮编集
        self.zips = self.stateZips[selectedState];
        
        // 重新加载邮编滚轮，默认选中邮编首行
        [self.dependentPicker reloadComponent:kZipComponent];
        [self.dependentPicker selectRow:0 inComponent:kZipComponent animated:YES];
        
    }
}
#pragma mark 滚轮的宽
- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component {
    CGFloat pickerWidth = pickerView.bounds.size.width;
    // 州滚轮占1/3、邮编滚轮占2/3
    if (component == kZipComponent) {
        return pickerWidth/3;
    } else {
        return 2 * pickerWidth/3;
    }
}

@end

9. CustomPickerViewController.m

//
//  CustomPickerViewController.m
//  7.1-创建Pickers应用程序
//
//  Created by LinKun on 16/7/16.
//  Copyright © 2016年 Apress. All rights reserved.
//

#import "CustomPickerViewController.h"
#import <AudioToolbox/AudioToolbox.h>

@interface CustomPickerViewController () <UIPickerViewDelegate, UIPickerViewDataSource>
/** 自定义滚轮 */
@property (weak, nonatomic) IBOutlet UIPickerView *customPicker;
/** 显示胜利结果的标签 */
@property (weak, nonatomic) IBOutlet UILabel *winLabel;
/** 游戏开始按钮 */
@property (weak, nonatomic) IBOutlet UIButton *button;
/** 数据：图片 */
@property (strong, nonatomic) NSArray *images;
// 声音
@property (assign, nonatomic) SystemSoundID winSoundID;
@property (assign, nonatomic) SystemSoundID crushSoundID;

@end

@implementation CustomPickerViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    // 加载数据
    self.images = @[[UIImage imageNamed:@"seven"],
                    [UIImage imageNamed:@"bar"],
                    [UIImage imageNamed:@"crown"],
                    [UIImage imageNamed:@"cherry"],
                    [UIImage imageNamed:@"lemon"],
                    [UIImage imageNamed:@"apple"]];
    
    // 游戏开始初始化结果框为空
    self.winLabel.text = @" ";
}

#pragma mark - 游戏逻辑
- (IBAction)spin:(UIButton *)sender {
    BOOL win = NO;
    /** 保存连续相同的图片的个数 */
    int numInRow = 1;
    /** 前一张图片索引 */
    int lastVal = -1;
    
    for (int i = 0; i < 5; i++) {
        /** 随机选择一张图片索引作为当前图片索引 */
        int newValue = arc4random_uniform((uint)[self.images count]);
        if (newValue == lastVal) {
            numInRow++;
        } else {
            numInRow = 1;
        }
        lastVal = newValue;
        
        // 选取器滚动到新值
        [self.customPicker selectRow:newValue inComponent:i animated:YES];
        [self.customPicker reloadComponent:i];
        if (numInRow >= 3) {
            win = YES;
        }
    }
    
    if (_crushSoundID == 0) {
        NSString *path = [[NSBundle mainBundle] pathForResource:@"crunch" ofType:@"wav"];
        NSURL *soundURL = [NSURL fileURLWithPath:path];
        AudioServicesCreateSystemSoundID((__bridge CFURLRef)soundURL, &_crushSoundID);
    }
    AudioServicesPlaySystemSound(_crushSoundID);
    if (win) {
        [self performSelector:@selector(playWinSound) withObject:nil afterDelay:.5];
        
    } else {
        [self performSelector:@selector(showButton) withObject:nil afterDelay:.5];
    }
    self.button.hidden = YES;
    self.winLabel.text = @" ";
}

#pragma mark -
#pragma mark 数据源
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
    return 5;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
    return [self.images count];
}

#pragma mark - 选取器委托
#pragma mark 行视图数据
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view {
    UIImage *image = self.images[row];
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
    return imageView;
}
#pragma mark 滚轮行高
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component {
    return 100;
}
#pragma mark - 隐藏按钮
- (void)showButton {
    self.button.hidden = NO;
}
#pragma mark - 播放声音
- (void)playWinSound {
    if (_winSoundID == 0) {
        NSURL *soundURL = [[NSBundle mainBundle] URLForResource:@"win" withExtension:@"wav"];
        AudioServicesCreateSystemSoundID((__bridge CFURLRef)soundURL, &_winSoundID);
    }
    AudioServicesPlaySystemSound(_winSoundID);
    self.winLabel.text = @"WINNER!";
    [self performSelector:@selector(showButton) withObject:nil afterDelay:1.5];
}

@end