1 #pragma mark -- 里程数按钮的点击事件
 2
 3 - (void)mileageBtnClicked:(UIButton *)sender {
 4
 5     UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"里程数/km\n\n\n\n\n\n\n\n" message:nil preferredStyle:UIAlertControllerStyleAlert];
 6
 7     UIPickerView *mileage = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 40, 270, 150)];
 8
 9     //指定Delegate
10
11     mileage.delegate = self;
12
13     //显示选中框
14
15     mileage.showsSelectionIndicator = YES;
16
17     [alert.view addSubview:mileage];
18
19
20
21     UIAlertAction *ok = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
22
23         NSInteger row = [mileage selectedRowInComponent:0];
24
25         NSString *mileageNum = [pickerData objectAtIndex:row];
26
27         mileageLabel.text = [NSString stringWithFormat:@"%@km", mileageNum];
28
29     }];
30
31
32
33     UIAlertAction *cancel = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
34
35     }];
36
37
38
39     [alert addAction:ok];
40
41     [alert addAction:cancel];
42
43     [self presentViewController:alert animated:YES completion:^{ }];
44
45
46
47     pickerData = [[NSArray alloc] initWithObjects:@"3000",@"3500",@"8000",@"8500",@"13000",@"13500",@"18000",@"18500",@"23000",@"23500",@"28500",@"33000",@"33500",@"38000",@"38500",@"43000",@"43500",@"48000",@"48500",@"53000",@"53500",@"58000",@"58500", nil];
48
49 }
50
51  #pragma mark -- UIPickerViewDataSource
52
53 //返回显示的列数
54
55 - (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
56
57     return 1;
58
59 }
60
61 //返回显示的行数
62
63 - (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
64
65     return pickerData.count;
66
67 }
68
69 #pragma mark -- UIPickerViewDelegate
70
71 //返回当前行的内容
72
73 - (nullable NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component __TVOS_PROHIBITED {
74
75     return [pickerData objectAtIndex:row];
76
77 }
78
79