iOS中UIPickerView实现省/市连动

 1 #import <UIKit/UIKit.h>
 2 
 3 @interface ViewController : UIViewController<UIPickerViewDelegate,UIPickerViewDataSource>
 4 @property(strong,nonatomic) UIPickerView *myPickView;
 5 @property(strong,nonatomic) NSArray *array;//用于存储数据
 6 @property(strong,nonatomic) NSMutableArray *provinceArray;//省份数组
 7 @property(strong,nonatomic) NSMutableArray *cityArray;//城市数组
 8 @property(strong,nonatomic) UIAlertController *alterController;
 9 @property(strong,nonatomic) UIAlertAction *actionA;
10 @property(strong,nonatomic) UIAlertAction *actionB;
11 
12 @end

 1 #import "ViewController.h"
 2 
 3 @interface ViewController ()
 4 
 5 
 6 @end
 7 
 8 @implementation ViewController
 9 
10 - (void)viewDidLoad {
11     [super viewDidLoad];
12     //初始化
13     self.provinceArray=[NSMutableArray array];
14     self.cityArray=[NSMutableArray array];
15     
16     self.myPickView=[[UIPickerView alloc] initWithFrame:CGRectMake(30, 100, 350, 200)];
17     self.myPickView.backgroundColor=[UIColor greenColor];
18     //指定代理
19     self.myPickView.delegate=self;
20     self.myPickView.dataSource=self;
21     
22     [self.view addSubview:self.myPickView];
23     
24     //提取文件
25     NSString *path=[[NSBundle mainBundle] pathForResource:@"city" ofType:@"plist"];
26     self.array=[NSArray arrayWithContentsOfFile:path];
27     
28     //把地区数据提取出来存储到 dic 字典中
29     for (NSDictionary *dic in self.array) {
30         //把字典 dic 中的省提取出来放到集合 provinceArray 中
31         [self.provinceArray addObject:dic[@"State"]];
32     }
33     //NSLog(@"%@",self.provinceArray);
34     
35     
36     
37     
38 }

 1 -(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
 2 {
 3     return 2; //输出的是两列
 4 }
 5 
 6 -(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
 7 {
 8     if (component==0) {
 9         return self.provinceArray.count;
10     }else
11     {
12         return self.cityArray.count;
13     }
14 }
15 
16 -(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
17 {
18     if (component==0) {
19         return [self.provinceArray objectAtIndex:row];
20     }
21     return [self.cityArray objectAtIndex:row];
22 }
23 
24 -(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
25 {
26     if (component==0)
27     {
28         //清除上次选择的城市
29         [self.cityArray removeAllObjects];
30         NSDictionary *dic=[self.array objectAtIndex:row];
31         NSArray *array1=dic[@"Cities"];
32         NSMutableArray *cityA=[NSMutableArray array];
33         for (NSDictionary *tempdic in array1) {
34             [cityA addObject:tempdic[@"city"]];
35         }
36         self.cityArray=cityA;
37         [self.myPickView selectRow:row inComponent:0 animated:YES];
38         //刷新组件
39         [self.myPickView reloadComponent:1];
40     }
41     if(component==1){
42         
43         NSInteger integerFirst=[self.myPickView selectedRowInComponent:0];
44         NSInteger integerTow=[self.myPickView selectedRowInComponent:1];
45         NSString *firstStr=[self.provinceArray objectAtIndex:integerFirst];
46         NSString *towStr=[self.cityArray objectAtIndex:integerTow];
47         NSString *str=[NSString stringWithFormat:@"您要选择的是:%@, %@吗？",firstStr,towStr];
48         self.alterController=[UIAlertController alertControllerWithTitle:@"系统提示" message:str preferredStyle:UIAlertControllerStyleAlert];
49         self.actionA=[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil];
50         self.actionB=[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:nil];
51         [self.alterController addAction:self.actionA];
52         [self.alterController addAction:self.actionB];
53         [self presentViewController:self.alterController animated:YES completion:nil];
54     }
55 
56 }
57 
58 -(CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component
59 {
60     return 40;
61 }
62 - (void)didReceiveMemoryWarning {
63     [super didReceiveMemoryWarning];
64     // Dispose of any resources that can be recreated.
65 }