Question

我使用UISlider在几分钟内（范围1 - 120）获取倒数计时器的输入，并将其显示在类似“01:30:00”的标签上。 i）我希望当用户设置计时器（使用滑块）来调整小时和分钟而不是秒。在用户开始倒计时后，秒数应开始计时。我怎样才能做到这一点？ ii）我无法更新倒计时标签。有人可以建议正确的代码吗？

-(IBAction)setTime:(id)sender {
totaltime=timeSlider.value;
hours = totaltime / 60;
minutes = (totaltime % 3600) % 60;
seconds = (totaltime % 3600) * 60;
[countDownLabel setFont:[UIFont fontWithName:@"DBLCDTempBlack" size:45]];
countDownLabel.text = [NSString stringWithFormat:@"%.2i:%.2i:%.2i", hours, minutes, seconds]; }

 -(void)countdown {
 totaltime -=1; 


if(minutes == 0) { [timer invalidate]; }    
 [countDownLabel setFont:[UIFont fontWithName:@"DBLCDTempBlack" size:45]];
 countDownLabel.text = [NSString stringWithFormat:@"%.2i:%.2i:%.2i", hours, minutes, seconds]; }
-(IBAction)fade {
timer = [NSTimer scheduledTimerWithTimeInterval:1.0
                                        target:self selector:@selector (countdown)  userInfo:nil repeats:YES]; }

Answer 1

-(IBAction)setTime:(id)sender {
totaltime=timeSlider.value;
hours = totaltime / 60;
minutes = (totaltime % 3600) % 60;
seconds = (totaltime % 3600) * 60;
[countDownLabel setFont:[UIFont fontWithName:@"DBLCDTempBlack" size:45]];
countDownLabel.text = [NSString stringWithFormat:@"%.2i:%.2i:%.2i", hours, minutes, seconds]; }

 -(void)countdown {
 totaltime -=1; 
totaltime=timeSlider.value;
hours = totaltime / 60;
minutes = (totaltime % 3600) % 60;
seconds = (totaltime % 3600) * 60;
countDownLabel.text = [NSString stringWithFormat:@"%.2i:%.2i:%.2i", hours, minutes, seconds];


if(minutes == 0) { [timer invalidate]; }    
 [countDownLabel setFont:[UIFont fontWithName:@"DBLCDTempBlack" size:45]];
 countDownLabel.text = [NSString stringWithFormat:@"%.2i:%.2i:%.2i", hours, minutes, seconds]; }
-(IBAction)fade {
timer = [NSTimer scheduledTimerWithTimeInterval:1.0
                                        target:self selector:@selector (countdown)  userInfo:nil repeats:YES]; }

Answer 2

您正在减少totalTime，但不会重新计算您的小时，分钟和秒。所以我想当你开始倒计时时，什么都没有改变？您需要在countdown方法中重新计算小时，分钟和秒。

iPhone：倒计时问题（00:00:00格式）

2 个答案: