iphone - 在日期选择器中选择日期后如何返回

Question

我在日期选择器中遇到问题。我什么时候点击日期选择器完成按钮。然后我的代码崩溃了。

-(IBAction)btn:(id)sender
{

    NSDateFormatter *df = [[NSDateFormatter alloc] init];
    df.dateStyle = NSDateFormatterMediumStyle;
    datelabel.text = [NSString stringWithFormat:@"%@",
                  [df stringFromDate:[NSDate date]]];
    [df release];
    [self.view addSubview:datelabel]; 
    [datelabel release];
        datePicker = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, 250, 325, 300)];
    datePicker.datePickerMode = UIDatePickerModeDate;
    datePicker.hidden = NO;
    datePicker.date = [NSDate date];   
    [datePicker addTarget:self
                   action:@selector(LabelChange:)
         forControlEvents:UIControlEventValueChanged];
    [self.view addSubview:datePicker];    
    [datePicker release];
          }
    - (void)LabelChange:(id)sender{
    NSDateFormatter *df = [[NSDateFormatter alloc] init];
    df.dateStyle = NSDateFormatterMediumStyle;
    datelabel.text = [NSString stringWithFormat:@"%@",
                  [df stringFromDate:datePicker.date]];  
                }
    UIToolbar *toolbar = [[UIToolbar alloc] init];
    toolbar.barStyle = UIBarStyleBlackOpaque;
    toolbar.frame=CGRectMake(0,4,datePicker.frame.size.width,40);
    [datePicker addSubview:toolbar];    
    UIBarButtonItem *flexibleSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
    UIBarButtonItem *doneBtn=[[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStyleBordered target:self action:@selector(DoneSelected)];
    [toolbar setItems:[NSArray arrayWithObjects:flexibleSpace,doneBtn,nil]];
    [flexibleSpace release];
}

Answer 1

-(void)DoneSelected
{
   your implementation code
}