我用UIDatePicker
實行倒計時timer.After加載視圖datePickerMode
集CountDownTimer後:如何繼續倒計時關閉的ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.countDownTimer.datePickerMode=UIDatePickerModeCountDownTimer;
}
首先,設置倒計時時間UIDatePicker
,然後按下按鈕啓動倒計時:
- (IBAction)StartCountdown:(id)sender {
[sender setTitle:@"Cancel" forState:UIControlStateNormal];
countDownInterval = (NSTimeInterval)countDownTimer.countDownDuration;
remainder = countDownInterval;
afterRemainder = countDownInterval - remainder % 60 ;
//call updateCountDown()
timer=[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(updateCountDown) userInfo:nil repeats:YES];
}
呼叫updateCountDown()
:
-(void)updateCountDown{
afterRemainder --;
int hours = (int)(afterRemainder/(60*60));
int mins = (int)(((int)afterRemainder/60)-(hours * 60));
int secs = (int)(((int)afterRemainder - (60 * mins) - (60 * hours *60)));
NSString *displayText = [[NSString alloc]initWithFormat:@"%02u : %02u : %02u",hours,mins,secs];
self.displayLabel.text = displayText;
}
動作可以正常執行,但是當我跳出這個視圖並且不會執行定時器爲零時,我該如何操作定時器可以在跳轉視圖後持續嗎?
意味着你需要運行要去另一個觀點也經過? –
我想你在應用程序委託中聲明方法,然後啓動計時器並訪問另一個視圖。 –
我有一個'viewcontroller'命名'timeViewContorller',我在視圖設置'UIDatePicker'並設置'button'來啓動並取消它。 – CHUB