選擇器，我想大家都不陌生，當需要用戶去選擇某些范圍值內的一個固定值時，我們會采用選擇器的方式。選擇器可以直觀的提示用戶選擇的值范圍、統一信息的填寫格式，同時也方便用戶快速的進行選擇，比如對於性別，正常情況下就只有男女兩種情況，那這時候用一個選擇器給用戶進行選擇的話，可以避免錯誤數據的輸入，也更方便用戶去填寫。再比如需要獲取用戶的生日信息時，采用選擇器的方式可以統一生日的格式，如果讓用戶自行輸入的話，可能會出現各種各樣的生日信息格式，不利於數據的存儲，但是采用選擇器的方式的話，用戶可找到對應的日期進行選擇即可。

在iOS有專門的一個選擇器類UIPickerView，進入UIPickerView的頭文件，我們可以發現 UIPickerView直接繼承了UIView，其事件處理通過代理方法完成，所以創建UIPickerView的時候記得簽它的代理UIPickerViewDataSource和UIPickerViewDelegate。其實它和UITbleView有點像，不過UIPickerView還多了個列屬性，UITbleView我們都很熟了，所以可以對比UITbleView的相關屬性和代理方法來學習記憶UIPickerView。

一． UIPickerView的代理方法

（1）UIPickerViewDataSource對應的代理方法有（其代理方法必須要實現）：

返回顯示的列數

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView;

返回每一列中需要顯示的行數

復制代碼 代碼如下:
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component;

（2）UIPickerViewDelegate對應的代理方法（其代理方法根據需求進行選擇性實現）：

返回每一列的寬度

復制代碼 代碼如下:
- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component;

返回每一列的高度

復制代碼 代碼如下:
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component ;

返回UIPickerView控件中指定列的列表項的要顯示的內容

復制代碼 代碼如下:
- (nullable NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component ;

返回UIView，作為該UIPickerView控件中指定列的指定行的顯示視圖

復制代碼 代碼如下:
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(nullable UIView *)view ;

選擇指定列中的指定行

復制代碼 代碼如下:
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component ;

二、UIPickerView和UIDatePicker。

UIDatePicker是系統幫我們封裝好的一個時間日期選擇器，繼承於UIControl，UIDatePicker有一定的局限性，因為它只有四種顯示樣式：

UIDatePickerModeTime,     
UIDatePickerModeDate,     
UIDatePickerModeDateAndTime, 
UIDatePickerModeCountDownTimer,

如果需求和這四種樣式都不符合的話，那麼就沒辦法使用UIDatePicker，比如當只需要顯示年、月信息的時候，顯然UIDatePicker沒辦法滿足我們的需求，那這時我們只能通過UIPickerView來自定義自己想要的選擇器。

三、UIPickerView的自定義使用

（1）創建基類繼承於UIView的WXZBasePickView。

我們常見的選擇器的樣式是一個帶透明背景色的view，底部是內容的選擇器，有確定和取消按鈕，大致如圖：

所以我們創建一個基類view，這個view的樣式如圖所示樣式，之後根據內容的差別創建基於該view的選擇器。

在.h中聲明各個屬性及方法

#import <UIKit/UIKit.h>

@interface WXZBasePickView : UIView

@property (nonatomic, strong) UIView *contentView;

//選擇器
@property (nonatomic, strong)UIPickerView *pickerView;
//取消按鈕
@property (nonatomic, strong)UIButton *cancelButton;
 //確定按鈕
@property (nonatomic, strong)UIButton *confirmButton;

//選擇器每一列的高度
@property (nonatomic, assign)CGFloat pickerViewHeight;

/**
 * 創建視圖,初始化視圖時初始數據
 */
- (void)initPickView;

/**
 * 確認按鈕的點擊事件
 */
- (void)clickConfirmButton;

/**
 * pickerView的顯示
 */
- (void)show;

/**
 * 移除pickerView
 */
- (void)disMiss;


@end

在.m中實現相關方法

#import "WXZBasePickView.h"
#define ScreenWidth [UIScreen mainScreen].bounds.size.width
#define ScreenHeight [UIScreen mainScreen].bounds.size.height
@implementation WXZBasePickView

- (instancetype)init
{
  self = [super init];
  if (self) {

    _pickerViewHeight   = 250;
    self.bounds = [UIScreen mainScreen].bounds;
    self.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.64];
    self.layer.opacity = 0.0;

    UITapGestureRecognizer *tap=[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(disMiss)];
    self.userInteractionEnabled = YES;
    [self addGestureRecognizer:tap];

    [self addSubview:self.contentView];
    [self.contentView addSubview:self.pickerView];
    [self.contentView addSubview:self.cancelButton];
    [self.contentView addSubview:self.confirmButton];

    [self initPickView];
   }
  return self;
}
//初始化選擇器內容，創建子類時需實現該父類方法
-(void)initPickView{

}
//點擊確定按鈕
- (void)clickConfirmButton
{
  [self disMiss];
}

//點擊取消按鈕
- (void) clickCancelButton
{
  [self disMiss];
}

//顯示選擇器
 - (void)show
{
  [[UIApplication sharedApplication].keyWindow addSubview:self];
  [self setCenter:[UIApplication sharedApplication].keyWindow.center];
  [[UIApplication sharedApplication].keyWindow bringSubviewToFront:self];


    CGRect frame = self.contentView.frame;
    frame.origin.y -= self.contentView.frame.size.height;
    [UIView animateWithDuration:0.4 delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
      [self.layer setOpacity:1.0];
      self.contentView.frame = frame;

    } completion:^(BOOL finished) {
    }];

  }

//移除選擇器
- (void)disMiss
{

    CGRect frame = self.contentView.frame;
    frame.origin.y += self.contentView.frame.size.height;
    [UIView animateWithDuration:0.4 delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
      [self.layer setOpacity:0.0];
      self.contentView.frame = frame;
    } completion:^(BOOL finished) {
      [self removeFromSuperview];
    }];

}
//設置選擇器的高度
- (void)setPickerViewHeight:(CGFloat)pickerViewHeight
{
  _pickerViewHeight = pickerViewHeight;
  self.contentView.frame = CGRectMake(self.contentView.frame.origin.x, self.contentView.frame.origin.y, self.contentView.frame.size.width, pickerViewHeight);
}

- (UIView *)contentView
{
  if (!_contentView) {

    _contentView = [[UIView alloc]initWithFrame:CGRectMake(0, ScreenHeight, ScreenWidth, self.pickerViewHeight)];
    [_contentView setBackgroundColor:[UIColor whiteColor]];
  }
  return _contentView;
}


- (UIPickerView *)pickerView
{
  if (!_pickerView) {

    _pickerView = [[UIPickerView alloc]initWithFrame:CGRectMake(0, 0, self.contentView.frame.size.width, self.contentView.frame.size.height)];
    [_pickerView setBackgroundColor:[UIColor whiteColor]];

  }
  return _pickerView;
}

- (UIButton *)cancelButton
{
  if (!_cancelButton) {

    _cancelButton = [[UIButton alloc]initWithFrame:CGRectMake(16, 0, 44, 44)];
    [_cancelButton setTitle:@"取消" forState:UIControlStateNormal];
    [_cancelButton setTitleColor:[UIColor grayColor] forState:UIControlStateNormal];

    [_cancelButton.titleLabel setFont:[UIFont systemFontOfSize:16]];
    [_cancelButton addTarget:self action:@selector(clickCancelButton) forControlEvents:UIControlEventTouchUpInside];
  }
  return _cancelButton;
}

- (UIButton *)confirmButton
{
  if (!_confirmButton) {

    _confirmButton = [[UIButton alloc]initWithFrame:CGRectMake(self.contentView.frame.size.width - self.cancelButton.frame.size.width - self.cancelButton.frame.origin.x, self.cancelButton.frame.origin.y, self.cancelButton.frame.size.width, self.cancelButton.frame.size.height)];
    [_confirmButton setTitle:@"確定" forState:UIControlStateNormal];
    [_confirmButton setTitleColor:[UIColor blueColor] forState:UIControlStateNormal];

    [_confirmButton.titleLabel setFont:[UIFont systemFontOfSize:16]];
    [_confirmButton addTarget:self action:@selector(clickConfirmButton) forControlEvents:UIControlEventTouchUpInside];
  }
  return _confirmButton;
}


@end

(2)、自定義一個日期選擇器，可選擇顯示年、月或者年、月、日以及是否顯示“至今”選項。

創建繼承於我們自定義好的WXZBasePickView的日期選擇器WXZPickDateView

.h聲明相關屬性和方法

#import "WXZBasePickView.h"
@class WXZBasePickView;
//選擇器的選擇代理方法
@protocol PickerDateViewDelegate<NSObject>
- (void)pickerDateView:(WXZBasePickView *)pickerDateView selectYear:(NSInteger)year selectMonth:(NSInteger)month selectDay:(NSInteger)day;
@end

@interface WXZPickDateView : WXZBasePickView

@property(nonatomic, weak)id <PickerDateViewDelegate>delegate ;
@property(nonatomic, assign)BOOL isAddYetSelect;//是否增加至今的選項
@property(nonatomic, assign)BOOL isShowDay;//是否顯示日
//設置默認顯示的值
-(void)setDefaultTSelectYear:(NSInteger)defaultSelectYear defaultSelectMonth:(NSInteger)defaultSelectMonth defaultSelectDay:(NSInteger)defaultSelectDay;

@end

.m實現相關方法

#import "WXZPickDateView.h"
@interface WXZPickDateView()<UIPickerViewDataSource, UIPickerViewDelegate>
/** 選擇的年 */
@property (nonatomic, assign)NSInteger selectYear;
/** 選擇的月 */
@property (nonatomic, assign)NSInteger selectMonth;
/** 選擇的日 */
@property (nonatomic, assign)NSInteger selectDay;
@property (nonatomic, assign)NSInteger currentYear;
@property (nonatomic, assign)NSInteger currentMonth;
@property (nonatomic, assign)NSInteger currentDay;
@property (nonatomic, assign)NSInteger defaultYear;
@property (nonatomic, assign)NSInteger defaultMonth;
@property (nonatomic, assign)NSInteger defaultDay;

@property (nonatomic, assign)NSInteger minShowYear;
@property (nonatomic, assign)NSInteger yearSum;
@end
@implementation WXZPickDateView

- (void)initPickView
{
  [super initPickView];
  _minShowYear = 1940;//最小年份
  NSCalendar *gregorian = [[NSCalendar alloc]initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
  // 獲取當前日期
  NSDate* dt = [NSDate date];
  // 指定獲取指定年、月、日、時、分、秒的信息
  unsigned unitFlags = NSCalendarUnitYear |
  NSCalendarUnitMonth | NSCalendarUnitDay |
  NSCalendarUnitHour | NSCalendarUnitMinute |
  NSCalendarUnitSecond | NSCalendarUnitWeekday;
  // 獲取不同時間字段的信息
  NSDateComponents* comp = [gregorian components: unitFlags fromDate:dt];

  _yearSum = comp.year-_minShowYear+1;
  _currentYear=comp.year;
  _currentMonth=comp.month;
  _currentDay=comp.day;


  _selectYear = comp.year;
  _selectMonth = comp.month;
  _selectDay  = comp.day;

  _defaultYear = comp.year;
  _defaultMonth = comp.month;
  _defaultDay=comp.day;
  [self.pickerView setDelegate:self];
  [self.pickerView setDataSource:self];

}
-(void)setDefaultTSelectYear:(NSInteger)defaultSelectYear defaultSelectMonth:(NSInteger)defaultSelectMonth defaultSelectDay:(NSInteger)defaultSelectDay{

  if (defaultSelectYear!=0) {
   _defaultYear=defaultSelectYear;
  }

  if (defaultSelectMonth!=0) {
    _defaultMonth = defaultSelectMonth;
  }

  if (defaultSelectDay!=0) {
     _defaultDay=defaultSelectDay;
  }


  if (defaultSelectYear==-1) {
    _defaultYear=_currentYear+1;
    _defaultMonth=1;
    _defaultDay=1;
  }


  [self.pickerView selectRow:(_defaultYear - _minShowYear) inComponent:0 animated:NO];
  [self.pickerView reloadComponent:1];
  [self.pickerView selectRow:(_defaultMonth - 1) inComponent:1 animated:NO];
  if (_isShowDay==YES) {
    [self.pickerView reloadComponent:2];
    [self.pickerView selectRow:_defaultDay inComponent:1 animated:NO];
  }

  [self refreshPickViewData];

}
-(void)setIsAddYetSelect:(BOOL)isAddYetSelect{
  _isAddYetSelect = isAddYetSelect;
}


- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
//判斷是否要顯示日，如果顯示則返回3列，反之返回2列
  if (_isShowDay==YES) {
    return 3;
  }else{
    return 2;
  }
}

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
  if (component == 0) {
    if (_isAddYetSelect==YES) {
      //顯示至今選項的話，需要比總共要顯示的年份多返回一行
      return self.yearSum+1;

    }else{

      return self.yearSum;
    }
  }else if(component == 1) {
    NSInteger yearSelected = [pickerView selectedRowInComponent:0] + self.minShowYear;
    if (yearSelected==_currentYear+1) {
      //至今選項的時候月份信息不返回
      return 0;
    }else{

      return 12;
    }
  }else {
    NSInteger yearSelected = [pickerView selectedRowInComponent:0] + self.minShowYear;
    if (yearSelected==_currentYear+1) {
       //至今選項的時候日信息不返回
      return 0;
    }else{
    NSInteger yearSelected = [pickerView selectedRowInComponent:0] + self.minShowYear;
    NSInteger monthSelected = [pickerView selectedRowInComponent:1] + 1;
    return [self getDaysWithYear:yearSelected month:monthSelected];
    }
  }


}
//根據年、月判斷日期天數
- (NSInteger)getDaysWithYear:(NSInteger)year
            month:(NSInteger)month
{
  switch (month) {
    case 1:
      return 31;
      break;
    case 2:
      if (year%400==0 || (year%100!=0 && year%4 == 0)) {
        return 29;
      }else{
        return 28;
      }
      break;
    case 3:
      return 31;
      break;
    case 4:
      return 30;
      break;
    case 5:
      return 31;
      break;
    case 6:
      return 30;
      break;
    case 7:
      return 31;
      break;
    case 8:
      return 31;
      break;
    case 9:
      return 30;
      break;
    case 10:
      return 31;
      break;
    case 11:
      return 30;
      break;
    case 12:
      return 31;
      break;
    default:
      return 0;
      break;
  }
}
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component
{
  //每一行的高度
  return 36;
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{

  NSInteger selectYear;
  NSInteger selectMonth;

  switch (component) {
    case 0:

      [pickerView reloadComponent:1];
      if (_isAddYetSelect==YES) {
        selectYear = row+_minShowYear+1;
      }else{
        selectYear = row+_minShowYear;
      }
      if (_isShowDay==YES) {
        [pickerView reloadComponent:2];
      }
      break;
    case 1:
      selectMonth = row+1;
      if (_isShowDay==YES) {
        [pickerView reloadComponent:2];
      }
    default:
      break;
  }

  [self refreshPickViewData];

}


- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(nullable UIView *)view
{

  NSString *text;
  if (component == 0) {

    if (_isAddYetSelect==YES) {

      if (row+_minShowYear==_currentYear+1) {
        text=@"至今";

      }else{


        text = [NSString stringWithFormat:@"%zd年", row + _minShowYear];

      }

    }else{

      text = [NSString stringWithFormat:@"%zd年", row + _minShowYear];
    }

  }else if (component == 1){
    if (_isAddYetSelect==YES) {
      NSInteger yearSelected = [pickerView selectedRowInComponent:0] + self.minShowYear;
      if (yearSelected==_currentYear+1) {
        text = [NSString stringWithFormat:@""];
      }else{
        text = [NSString stringWithFormat:@"%zd月", row + 1];
      }
    }else{
      text = [NSString stringWithFormat:@"%zd月", row + 1];
    }


  }else{
    text = [NSString stringWithFormat:@"%zd日", row + 1];
  }

  UILabel *label = [[UILabel alloc]init];
  label.textAlignment = 1;
  label.font = [UIFont systemFontOfSize:16];
  label.text = text;

  return label;
}


- (void)clickConfirmButton
{


  if ([self.delegate respondsToSelector:@selector(pickerDateView:selectYear:selectMonth:selectDay:)]) {

    [self.delegate pickerDateView:self selectYear:self.selectYear selectMonth:self.selectMonth selectDay:self.selectDay];

  }

  [super clickConfirmButton];

}



- (void)refreshPickViewData
{

  self.selectYear = [self.pickerView selectedRowInComponent:0] + self.minShowYear;

  self.selectMonth = [self.pickerView selectedRowInComponent:1] + 1;
  if (_isShowDay==YES) {
     self.selectDay  = [self.pickerView selectedRowInComponent:2] + 1;
  }

}


- (void)setYearLeast:(NSInteger)yearLeast
{
  _minShowYear = yearLeast;
}

- (void)setYearSum:(NSInteger)yearSum
{
  _yearSum = yearSum;
}

-(void)setIsShowDay:(BOOL)isShowDay{
  _isShowDay=isShowDay;
}

@end

（3） 創建繼承於WXZBasePickView的時間選擇器WXZPickTimeView。

.h聲明屬性及相關方法

#import "WXZBasePickView.h"
@class WXZPickTimeView;

@protocol PickTimeViewDelegate<NSObject>
- (void)pickerTimeView:(WXZPickTimeView *)pickerTimeView selectHour:(NSInteger)hour selectMinute:(NSInteger)minute ;

@end
@interface WXZPickTimeView : WXZBasePickView
@property(nonatomic, weak)id <PickTimeViewDelegate>delegate ;

-(void)setDefaultHour:(NSInteger)hour defaultMinute:(NSInteger)minute ;
@end

.m實現相關方法

#import "WXZPickTimeView.h"
@interface WXZPickTimeView () <UIPickerViewDataSource, UIPickerViewDelegate>{
  UIDatePicker  *_datePicker;
}

@property (nonatomic, assign)NSInteger selectHour;
@property (nonatomic, assign)NSInteger selectMinute;
@property (nonatomic, assign)NSInteger day;
@property (nonatomic, assign)NSInteger defaultHour;
@property (nonatomic, assign)NSInteger defaultMinute;

@end

@implementation WXZPickTimeView

 - (void)initPickView
{
  [super initPickView];


  NSCalendar *gregorian = [[NSCalendar alloc]
               initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
  // 獲取當前日期
  NSDate* dt = [NSDate date];
  // 定義一個時間字段的旗標，指定將會獲取指定年、月、日、時、分、秒的信息
  unsigned unitFlags = NSCalendarUnitYear |
  NSCalendarUnitMonth | NSCalendarUnitDay |
  NSCalendarUnitHour | NSCalendarUnitMinute |
  NSCalendarUnitSecond | NSCalendarUnitWeekday;
  // 獲取不同時間字段的信息
  NSDateComponents* comp = [gregorian components: unitFlags
                     fromDate:dt];

  _selectHour=comp.hour;
  _selectMinute=comp.minute;

  [self.pickerView setDelegate:self];
  [self.pickerView setDataSource:self];

  [self.pickerView selectRow:_selectHour inComponent:0 animated:NO];
  [self.pickerView selectRow:_selectMinute inComponent:1 animated:NO];


}
-(void)setDefaultHour:(NSInteger)hour defaultMinute:(NSInteger)minute{

  if (hour!=0) {

   _defaultHour=hour;


  }else{
    _defaultHour=_selectHour;

  }
  if (minute!=0) {


    _defaultMinute = minute;

  }else{

    _defaultMinute=_selectMinute;
  }
  [self.pickerView selectRow:_defaultHour inComponent:0 animated:NO];
  [self.pickerView reloadComponent:1];
  [self.pickerView selectRow:_defaultMinute inComponent:1 animated:NO];
  [self refreshPickTimeViewData];

}

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
  return 2;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
  if (component == 0) {
    return 24;
  }else {
    return 60;
  }
}

- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component
{
  return 36;
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
  switch (component) {
    case 0:
      [pickerView reloadComponent:1];

      break;
    case 1:

    default:
      break;
  }

  [self refreshPickTimeViewData];
}

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(nullable UIView *)view
{

  NSString *text;
  if (component == 0) {
    if (row<10) {
      text = [NSString stringWithFormat:@"0%zd時", row];
    }else{
      text = [NSString stringWithFormat:@"%zd時", row];
    }
  }else if (component == 1){
    if (row<10) {
      text = [NSString stringWithFormat:@"0%zd分", row ];
    }else{
      text = [NSString stringWithFormat:@"%zd分", row ];
    }
  }else{

  }

  UILabel *label = [[UILabel alloc]init];
  label.textAlignment = 1;
  label.font = [UIFont systemFontOfSize:16];
  label.text = text;
  return label;
}

- (void)clickConfirmButton
{
  if ([self.delegate respondsToSelector:@selector(pickerTimeView:selectHour:selectMinute:)]) {

    [self.delegate pickerTimeView:self selectHour:self.selectHour selectMinute:self.selectMinute];

  }

  [super clickConfirmButton];
}

- (void)refreshPickTimeViewData
{
  self.selectHour = [self.pickerView selectedRowInComponent:0];
  self.selectMinute = [self.pickerView selectedRowInComponent:1];

}
@end

（4）創建繼承於WXZBasePickView的城市選擇器WXZPickCityView。

.h聲明相關屬性和方法

#import "WXZBasePickView.h"
@class WXZPickCityView;

@protocol PickerCityViewDelegate<NSObject>

- (void)pickerArea:(WXZPickCityView *)pickerArea selectProvince:(NSString *)province selectCity:(NSString *)city;

@end
@interface WXZPickCityView : WXZBasePickView
@property(nonatomic, weak)id <PickerCityViewDelegate>delegate ;

/**設置默認的省市*/

-(void)setDefaultCity:(NSString *)defaultCity DefaultProvience:(NSString *)defaultProvience;
@end

.m實現相關方法

#import "WXZPickCityView.h"
@interface WXZPickCityView()<UIPickerViewDataSource, UIPickerViewDelegate>


@property (nonatomic, strong, nullable)NSArray *areaDataSource;

@property (nonatomic, strong, nullable)NSMutableArray *provinceArray;

@property (nonatomic, strong, nullable)NSMutableArray *cityArray;

@property (nonatomic, strong, nullable)NSMutableArray *selectedArray;//當前選中的數組

@property (nonatomic, strong, nullable)NSString *selectProvince;

@property (nonatomic, strong, nullable)NSString *selectCity;

@end

@implementation WXZPickCityView


- (void)initPickView
{
  [super initPickView];
  for (NSDictionary *dic in self.areaDataSource) {
    [self.provinceArray addObject:dic[@"state"]];
  }

  NSMutableArray *citysArr = [NSMutableArray arrayWithArray:[self.areaDataSource firstObject][@"cities"]];


  for (NSDictionary *dic in citysArr) {
    [self.cityArray addObject:dic[@"city"]];
  }

  self.selectProvince = self.provinceArray[0];
  self.selectCity = self.cityArray[0];


  [self.pickerView setDelegate:self];
  [self.pickerView setDataSource:self];

}

//設置默認顯示的省市
-(void)setDefaultCity:(NSString *)defaultCity DefaultProvience:(NSString *)defaultProvience{

  for (NSInteger i = 0; i<_provinceArray.count; i++) {

    if ([_provinceArray[i] isEqualToString:defaultProvience]) {

      [self.pickerView selectRow:i inComponent:0 animated:NO];
      self.selectedArray = self.areaDataSource[i][@"cities"];

      [self.cityArray removeAllObjects];
      [self.selectedArray enumerateObjectsUsingBlock:^(NSDictionary *obj, NSUInteger idx, BOOL * _Nonnull stop) {
        [self.cityArray addObject:obj[@"city"]];
      }];
      for (NSInteger j= 0; j<_cityArray.count; j++) {

        if ([defaultCity isEqualToString:_cityArray[j]]) {

          [self.pickerView selectRow:i inComponent:0 animated:NO];
          [self.pickerView reloadComponent:1];
          [self.pickerView selectRow:j inComponent:1 animated:NO];
          [self refreshSelectAreaData];
        }
      }
    }


  }

}


- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
  return 2;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
  if (component == 0) {
    return self.provinceArray.count;
  }else {
    return self.cityArray.count;
  }
}

- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component
{
  return 36;
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
  if (component == 0) {
    self.selectedArray = self.areaDataSource[row][@"cities"];

    [self.cityArray removeAllObjects];
    [self.selectedArray enumerateObjectsUsingBlock:^(NSDictionary *obj, NSUInteger idx, BOOL * _Nonnull stop) {
      [self.cityArray addObject:obj[@"city"]];
    }];


    [pickerView reloadComponent:1];
    [pickerView selectRow:0 inComponent:1 animated:YES];


  }else if (component == 1) {
    if (self.selectedArray.count == 0) {
      self.selectedArray = [self.areaDataSource firstObject][@"cities"];
    }

  }else{
  }

  [self refreshSelectAreaData];
}

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(nullable UIView *)view
{

  for(UIView *singleLine in pickerView.subviews)
  {
    if (singleLine.frame.size.height < 1)
    {
      singleLine.backgroundColor =[UIColor grayColor];
    }
  }
  NSString *text;
  if (component == 0) {
    text = self.provinceArray[row];
  }else if (component == 1){
    text = self.cityArray[row];
  }else{

  }

  UILabel *label = [[UILabel alloc]init];
  label.textAlignment = 1;
  label.font = [UIFont systemFontOfSize:16];
  label.text = text;

  return label;
}


- (void)clickConfirmButton
{

  [self.delegate pickerArea:self selectProvince:self.selectProvince selectCity:self.selectCity];

  [super clickConfirmButton];
}


- (void)refreshSelectAreaData
{
  NSInteger provienceIndex = [self.pickerView selectedRowInComponent:0];
  NSInteger cityIndex = [self.pickerView selectedRowInComponent:1];

  self.selectProvince = self.provinceArray[provienceIndex];
  self.selectCity = self.cityArray[cityIndex];


}



- (NSArray *)areaDataSource
{
  if (!_areaDataSource) {
    NSString *path = [[NSBundle bundleForClass:[WXZPickCityView class]] pathForResource:@"area" ofType:@"plist"];
    _areaDataSource = [[NSArray alloc]initWithContentsOfFile:path];
  }
  return _areaDataSource;
}

- (NSMutableArray *)provinceArray
{
  if (!_provinceArray) {
    _provinceArray = [NSMutableArray array];
  }
  return _provinceArray;
}

- (NSMutableArray *)cityArray
{
  if (!_cityArray) {
    _cityArray = [NSMutableArray array];
  }
  return _cityArray;
}



- (NSMutableArray *)selectedArray
{
  if (!_selectedArray) {
    _selectedArray = [NSMutableArray array];
  }
  return _selectedArray;
}



@end

（5）創建繼承於WXZBasePickView的單列選擇器WXZCustomPickView，可根據傳進來的數組顯示相關的選擇內容

.h聲明相關屬性和方法

#import "WXZBasePickView.h"

@class WXZCustomPickView;

@protocol CustomPickViewDelegate<NSObject>
- (void)customPickView:(WXZCustomPickView *)customPickView selectedTitle:(NSString *)selectedTitle;
@end

@interface WXZCustomPickView :WXZBasePickView

@property (nonatomic, strong)NSMutableArray *dataArray;
@property(nonatomic, copy)NSString *defalutSelectRowStr;
@property(nonatomic, weak)id <CustomPickViewDelegate>delegate;
@end

.m實現相關方法

#import "WXZCustomPickView.h"
@interface WXZCustomPickView()<UIPickerViewDataSource, UIPickerViewDelegate>
/** 1.選中的字符串 */
@property (nonatomic, strong, nullable)NSString *selectedTitle;

@end

@implementation WXZCustomPickView


- (void)initPickView
{
  [super initPickView];

  _dataArray=[NSMutableArray mutableCopy];



  [self.pickerView setDelegate:self];
  [self.pickerView setDataSource:self];




}

-(void)setDefalutSelectRowStr:(NSString *)defalutSelectRowStr{
  _defalutSelectRowStr=defalutSelectRowStr;

  for (NSInteger i = 0; i<_dataArray.count; i++) {


    if ([_dataArray[i] isEqualToString:_defalutSelectRowStr]) {
      [self.pickerView reloadAllComponents];
      [self.pickerView selectRow:i inComponent:0 animated:NO];

    }
  }
}


- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
  return 1;
}

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

- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component
{
  return 36;
}

- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component
{

  return self.frame.size.width;

}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
  self.selectedTitle = self.dataArray[row];
}

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(nullable UIView *)view
{

  for(UIView *singleLine in pickerView.subviews)
  {
    if (singleLine.frame.size.height < 1)
    {
      singleLine.backgroundColor =[UIColor grayColor];
    }
  }

  UILabel *label = [[UILabel alloc]init];
  label.font=[UIFont systemFontOfSize:16];
  label.textAlignment = 1;

  label.text=self.dataArray[row];

    return label;



}
#pragma mark -點擊確定按鈕
- (void)clickConfirmButton
{
  [self.delegate customPickView:self selectedTitle:self.selectedTitle];

  [super clickConfirmButton];
}


- (void)setDataArray:(NSMutableArray *)dataArray
{
  _dataArray = dataArray;
  _selectedTitle = dataArray.firstObject;
  [self.pickerView reloadAllComponents];

}



@end

這樣，幾種類型的選擇器我們都定義好了，在需要選擇器的地方，根據需求創建相應的選擇器即可。

四、如何使用已創建好的自定義選擇器

引入自定義好的選擇器，聲明相關屬性，簽相關協議

#import "ViewController.h"
#import "WXZPickDateView.h"
#import "WXZPickAreaView.h"
#import "WXZPickTimeView.h"
#import "WXZCustomPickView.h"
@interface ViewController ()<PickerDateViewDelegate,PickerAreaViewDelegate,PickTimeViewDelegate,CustomPickViewDelegate>{
  UIButton *dateButton;
  UIButton *selectAreabutton;
  UIButton *selectTimeButton;
  UIButton *singlePickViewSelectButton;
  BOOL isShowDay;//是否顯示日信息
}

@end

創建相應的按鈕，觸發相應的選擇器

- (void)viewDidLoad {
  [super viewDidLoad];

  dateButton=[UIButton buttonWithType:UIButtonTypeCustom];
  dateButton.frame=CGRectMake(100, 100, 100, 50);
  [dateButton setTitle:@"選擇日期" forState:UIControlStateNormal];
  [self.view addSubview:dateButton];
  [dateButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
  [dateButton addTarget:self action:@selector(pickViewSelect:) forControlEvents:UIControlEventTouchUpInside];
  dateButton.tag = 1000;

   selectAreabutton=[UIButton buttonWithType:UIButtonTypeCustom];
  selectAreabutton.frame=CGRectMake(100, 200, 100, 50);
  [selectAreabutton setTitle:@"選擇地區" forState:UIControlStateNormal];
  [self.view addSubview:selectAreabutton];
  [selectAreabutton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
  [selectAreabutton addTarget:self action:@selector(pickViewSelect:) forControlEvents:UIControlEventTouchUpInside];
  selectAreabutton.tag = 1001;
  selectTimeButton=[UIButton buttonWithType:UIButtonTypeCustom];
  selectTimeButton.frame=CGRectMake(100, 300, 100, 50);
  [selectTimeButton setTitle:@"選擇時間" forState:UIControlStateNormal];
  [self.view addSubview:selectTimeButton];
  [selectTimeButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
  [selectTimeButton addTarget:self action:@selector(pickViewSelect:) forControlEvents:UIControlEventTouchUpInside];
  selectTimeButton.tag = 1002;

  singlePickViewSelectButton=[UIButton buttonWithType:UIButtonTypeCustom];
  singlePickViewSelectButton.frame=CGRectMake(100, 400, 100, 50);
  [singlePickViewSelectButton setTitle:@"單個數據選擇器" forState:UIControlStateNormal];
  [self.view addSubview:singlePickViewSelectButton];
  [singlePickViewSelectButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
  [singlePickViewSelectButton addTarget:self action:@selector(pickViewSelect:) forControlEvents:UIControlEventTouchUpInside];
  singlePickViewSelectButton.tag = 1003;

}

按鈕的點擊事件：

-(void)pickViewSelect:(UIButton *)button{
  if (button.tag==1000) {

      WXZPickDateView *pickerDate = [[WXZPickDateView alloc]init];


      [pickerDate setIsAddYetSelect:YES];//是否顯示至今選項
      [pickerDate setIsShowDay:YES];//是否顯示日信息
      [pickerDate setDefaultTSelectYear:2007 defaultSelectMonth:4 defaultSelectDay:1];//設定默認顯示的日期
      [pickerDate setValidTime:2010];

      [pickerDate setDelegate:self];

      [pickerDate show];
  }else if (button.tag==1001){
    WXZPickAreaView *pickerArea = [[WXZPickAreaView alloc]init];

    [pickerArea setDelegate:self];

    [pickerArea setDefaultCity:@"上海" DefaultProvience:@"上海"];

    [pickerArea show];
    [self.view endEditing:YES];
  }else if (button.tag==1002){
    WXZPickTimeView *pickerArea = [[WXZPickTimeView alloc]init];

    [pickerArea setDelegate:self];

    [pickerArea setDefaultHour:14 defaultMinute:20];

    [pickerArea show];
    [self.view endEditing:YES];
  }else{
    NSMutableArray *arrayData = [NSMutableArray arrayWithObjects:@"2k以下",@"2k-5k",@"5k-10k",@"10k-15k",@"15k-25k",@"25k-50k",@"50k以上", nil];

    WXZCustomPickView *pickerSingle = [[WXZCustomPickView alloc]init];

    [pickerSingle setDataArray:arrayData];
    [pickerSingle setDefalutSelectRowStr:arrayData[0]];


    [pickerSingle setDelegate:self];

    [pickerSingle show];
    [self.view endEditing:YES];

  }
}

選擇器的代理方法

-(void)pickerDateView:(WXZBasePickView *)pickerDateView selectYear:(NSInteger)year selectMonth:(NSInteger)month selectDay:(NSInteger)day{
  NSLog(@"選擇的日期是：%ld %ld %ld",year,month,day);
  if (isShowDay==YES) {
    [dateButton setTitle:[NSString stringWithFormat:@"%ld年 %ld月 %ld日",year,month,day] forState:UIControlStateNormal];
  }else{
    [dateButton setTitle:[NSString stringWithFormat:@"%ld年 %ld月",year,month] forState:UIControlStateNormal];
  }

}

-(void)pickerArea:(WXZPickAreaView *)pickerArea selectProvince:(NSString *)province selectCity:(NSString *)city{
  NSLog(@"省市的選擇%@ %@",province,city);
  [selectAreabutton setTitle:[NSString stringWithFormat:@"%@%@",province,city] forState:UIControlStateNormal];
}

-(void)customPickView:(WXZCustomPickView *)customPickView selectedTitle:(NSString *)selectedTitle{
  NSLog(@"選擇%@",selectedTitle);
  [singlePickViewSelectButton setTitle:selectedTitle forState:UIControlStateNormal];
}
-(void)pickerTimeView:(WXZPickTimeView *)pickerTimeView selectHour:(NSInteger)hour selectMinute:(NSInteger)minute{
  NSLog(@"選擇的時間：%ld %ld",hour,minute);
  [selectTimeButton setTitle:[NSString stringWithFormat:@"%ld時 %ld分",hour,minute] forState:UIControlStateNormal];
}

最後，看看效果圖：

有需要的可以下載demo看看

github地址：https://github.com/wxzwork/CustomPickView

demo地址：CustomPickView_jb51.rar

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持本站。