objective-c - 如何更改标签上的日期选择器选定值

Question

我想在标签上显示从日期选择器中选择的日期，但标签只显示当前日期它不显示我从日期选择器中选择的日期这是代码请告诉我如何随机更改文本标签从日期选择器中选择的日期

#import "ViewController.h"

@implementation ViewController
@synthesize datepicker,mylabel;


- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Release any cached data, images, etc that aren't in use.
}

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];
    NSDate *chosen = datepicker.date;
    NSDateFormatter *formatter = [[NSDateFormatter alloc]init];
    formatter.dateStyle = NSDateFormatterMediumStyle;
    mylabel.text = [formatter stringFromDate:chosen];
     [formatter release];    

    // Do any additional setup after loading the view, typically from a nib.

}

- (void)viewDidUnload
{

    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
}

- (void)viewDidDisappear:(BOOL)animated
{
    [super viewDidDisappear:animated];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}

@end

Answer 1

    // code for Date picker for current date

     datepicker=[[UIDatePicker alloc]initWithFrame:CGRectMake(0, 200, 320, 150)];
        //[self.view addSubview:datepicker];
        datepicker.date = [NSDate date];
        datepicker.datePickerMode=UIDatePickerModeDate;
        NSDateFormatter *df = [[NSDateFormatter alloc] init];
        df.timeStyle = NSDateFormatterNoStyle;

        label.text=[NSString stringWithFormat:@"%@",
                   [df stringFromDate:[NSDate date]]];
        df.dateFormat = @"yyyy-MM-dd";

    // set action for date picker

       [datepicker addTarget:self  action:@selector(DateChange:)
            forControlEvents:UIControlEventValueChanged];

    //method for change date

    - (void)DateChange:(id)sender
{
        NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
        [dateFormatter setDateFormat:@"dd-MM-yyyy"];
        label.text = [dateFormatter stringFromDate:datepicker.date];
        date.text=strDate;
}