091实现一个数字选择器

1 #import <UIKit/UIKit.h>
2 
3 @interface ViewController : UIViewController<UIPickerViewDataSource, UIPickerViewDelegate>
4 @end

 1 #import "ViewController.h"
 2 
 3 @interface ViewController ()
 4 - (void)layoutUI;
 5 @end
 6 
 7 @implementation ViewController
 8 
 9 - (void)viewDidLoad {
10     [super viewDidLoad];
11     
12     [self layoutUI];
13 }
14 
15 - (void)didReceiveMemoryWarning {
16     [super didReceiveMemoryWarning];
17     // Dispose of any resources that can be recreated.
18 }
19 
20 - (void)layoutUI {
21     UIPickerView *pikVCustom = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 0, 0, 0)];
22     pikVCustom.center = self.view.center;
23     pikVCustom.dataSource = self;
24     pikVCustom.delegate = self;
25     [pikVCustom selectRow:4 inComponent:0 animated:YES]; //设置第一个组件列选中第五行
26     [self.view addSubview:pikVCustom];
27 }
28 
29 #pragma mark - PickerView
30 - (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
31     return 3; //返回组件列数
32 }
33 
34 - (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
35     return 10; //返回组件行数
36 }
37 
38 - (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
39     return [NSString stringWithFormat:@"%ld-%ld", (long)component, (long)row];
40 }
41 
42 - (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
43     NSInteger selectedRowInFirstComponent = [pickerView selectedRowInComponent:0];
44     NSInteger selectedRowInSecondComponent = [pickerView selectedRowInComponent:1];
45     NSInteger selectedRowInThirdComponent = [pickerView selectedRowInComponent:2];
46     
47     NSString *strMessage = [NSString stringWithFormat:@"0-%ld, 1-%ld, 2-%ld",
48                             selectedRowInFirstComponent,
49                             selectedRowInSecondComponent,
50                             selectedRowInThirdComponent];
51     UIAlertView *alertV = [[UIAlertView alloc] initWithTitle:@"选择的内容"
52                                                      message:strMessage
53                                                     delegate:nil
54                                            cancelButtonTitle:nil
55                                            otherButtonTitles:@"确定", nil];
56     [alertV show];
57 }
58 
59 @end