UIPickerView的使用

UIPickerView继承自UIView,它的用法类似UITableView,需要设置数据源代理UIPickerViewDataSource和交互代理UIPickerViewDelegate

基本使用

• 创建并设置代理,我是用SB创建

  self.pickView.dataSource = self;
    self.pickView.delegate = self;

• 遵循 UIPickerViewDataSource协议方法

//返回d多少列
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
   
    return 1;
}

//每一列返回多好行
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    
    return 10;
}

• 遵循 UIPickerViewDelegate协议方法

//每行显示的内容
- (nullable NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
    
    return @"100";
}
//每行可以显示UIView视图 下面的这个方法
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(nullable UIView *)view {

}

//选中那一列的哪一行
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
    
}

使用二级联动

二级联动.png

数据模型

image.png image.png image.png

初始化控件

#import "CCStateTF.h"

#import "CCStateItem.h"

@interface CCStateTF()<UIPickerViewDataSource,UIPickerViewDelegate>

@property (nonatomic, weak) UIPickerView *pickView;

@property (nonatomic, strong) NSArray *datas;

///第一列选中的row数 既是省份
@property (nonatomic, assign) NSInteger selectIndexRow;

@end

@implementation CCStateTF

- (instancetype)initWithFrame:(CGRect)frame{
    if (self = [super initWithFrame:frame]) {
        [self setupChildContent];
    }
    
    return self;
}


- (void)awakeFromNib {
    [super awakeFromNib];
    [self setupChildContent];
}


- (void)setupChildContent{
    [self pickView];
}

- (void)initText {
    [self pickerView:self.pickView didSelectRow:0 inComponent:0 ];
}

//懒加载
- (UIPickerView *)pickView {
    if (!_pickView) {
        UIPickerView *pickView = [[UIPickerView alloc] init];
        pickView.dataSource = self;
        pickView.delegate = self;
        self.inputView = pickView;
        self.pickView = pickView;
        
        
    }
    
    return _pickView;
}

//初始化数据
- (NSArray *)datas{
    if (!_datas) {
        
        NSString *filePath = [[NSBundle mainBundle] pathForResource:@"provinces.plist" ofType:nil];
        NSArray *data = [NSArray arrayWithContentsOfFile:filePath];
        NSMutableArray *tempData = [NSMutableArray array];
        
        for (NSDictionary *dic in data) {
            CCStateItem *item = [CCStateItem stateItemWithDictionary:dic];
            [tempData addObject:item];
        }
        
        _datas = tempData;
        
    }
    
    return _datas;
}

代理方法

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

//每列返回多少行
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    
    if (component == 0) {
        //第一列返回的个数
        return self.datas.count;
    }
    CCStateItem *item = self.datas[self.selectIndexRow];
    return item.cities.count;
}

//返回的内容
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{
    
    //第一列
    if (component == 0) {
        CCStateItem *item = self.datas[row];
        return item.name;
    }
    //第二列
    CCStateItem *compItem = self.datas[self.selectIndexRow];
    return compItem.cities[row];
}

//选中那l一列的那一行
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
    if (component == 0) {
        //获取第一列 选中的是哪一行
        self.selectIndexRow = row;
        //选中
        [pickerView selectRow:0 inComponent:1 animated:YES];
        //刷新数据
        [pickerView reloadAllComponents];
        
    }
    
    //获取到选中的
    CCStateItem *item =  self.datas[self.selectIndexRow];
    NSString *name = item.name;
    //获取第一列x选中的 行数
    NSInteger seletCity = [pickerView selectedRowInComponent:1];
    NSString *city = item.cities[seletCity];
    
    self.text = [NSString stringWithFormat:@"%@-%@",name,city];
    
   
    
}