选择日期和时间的空间 也可作为倒计时空间 继承了UIControl 可做为活动空间使用
1.Mode
Date 仅显示日期，不显示时间
Time:仅显示时间，不显示日期
DateandTime:同时显示日期和时间
CountDownTimer:仅显示为倒计时器
2.Locale
的国家化Locale 通常无需手动设置 默认使用iOS系统的国际化Locale
3.Interval
仅当该UIDatePicker控件采用Time,DateandTime 和CountDownTimer三种模式时邮箱，设置空间上两个时间之间的间隔
4.Constraints
最小时间和最大时间
5.Timer
采用CountDownTimer模式时有效，作为倒计时控件时剩下的秒数
日期选择器：
self.dp=[[UIDatePicker alloc]initWithFrame:CGRectMake(0, 20, 400, 500)];
self.dp.datePickerMode=UIDatePickerModeDateAndTime;
[self.view addSubview:self.dp];
UIButton* btn=[UIButton buttonWithType:UIButtonTypeRoundedRect];
btn.frame=CGRectMake(200, 660, 40, 40);
[btn setTitle:@"确定" forState:UIControlStateNormal];
[btn addTarget:self action:@selector(clicked:) forControlEvents:
UIControlEventTouchUpInside];
[self.view addSubview:btn];
// Do any additional setup after loading the view, typically from a nib.
}
-(void)clicked:(id)sender{
NSLog(@"123");
NSDate* selected=[self.dp date];
NSDateFormatter* dateFormatter=[[NSDateFormatter alloc]init];
[dateFormatter setDateFormat:@"yyyy年MM月dd日 HH:mm+0800"];
NSString* destDateString=[dateFormatter stringFromDate:selected];
NSString* message=[NSString stringWithFormat:@"您选择的日期和时间是：%@",destDateString];
UIAlertView* alert=[[UIAlertView alloc]initWithTitle:@"日期和时间" message:message delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
[alert show];
}
倒计时器
需要一个NSTimer定时器定期更新控件的剩余时间
最重要的属性为:countDownDuration 该属性代表该倒计时器剩余时间 可修改剩余时间和获取
self.dp=[[UIDatePicker alloc]initWithFrame:CGRectMake(0, 20, 400, 500)];
self.dp.datePickerMode=UIDatePickerModeCountDownTimer;
[self.view addSubview:self.dp];
self.btn=[UIButton buttonWithType:UIButtonTypeRoundedRect];
self.btn.frame=CGRectMake(200, 660, 40, 40);
[self.btn setTitle:@"确定" forState:UIControlStateNormal];
[self.btn addTarget:self action:@selector(clicked:) forControlEvents:
UIControlEventTouchUpInside];
[self.view addSubview:self.btn];
// Do any additional setup after loading the view, typically from a nib.
}
-(void)clicked:(id)sender{
self.leftSeconds=self.dp.countDownDuration;
[self.dp setEnabled:NO];
[sender setEnabled:NO];
NSString* message=[NSString stringWithFormat:@"开始倒计时？您还成【%ldd】秒",(long)self.leftSeconds];
UIAlertView* alert=[[UIAlertView alloc]
initWithTitle:@"开始倒计时？" message:message delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
[alert show];
self.timer=[NSTimer scheduledTimerWithTimeInterval:60 target:self selector:@selector(tickDown) userInfo:nil repeats:YES];
}
-(void)tickDown{
self.leftSeconds-=60;
self.dp.countDownDuration=self.leftSeconds;
if (self.leftSeconds<=0) {
[self.timer invalidate];
self.dp.enabled=YES;
self.btn.enabled=YES;
}
}