timer

问题 I've written a code snipped that creates a timer with a 0 length time, and it does not immediately expire (which is what I expected). A very short sleep call does make it expire, but I'm confused as to why. The reason I care is that the code using this idea has a snippet that returns 0 on a low probability error, with the idea that the timer should be set to immediately expire, and retry a function. I do not believe that the nanosecond sleep needed here will affect my implementation, but it

问题 how to add a nice timer xaml : <ProgressBar x:Name="progressBar" Grid.Row="2" Grid.ColumnSpan="5" IsVisible="true" Progress="0.0" WidthRequest="300" HeightRequest="20" VerticalOptions="Center" HorizontalOptions="Center"> </ProgressBar> behind code : progressBar.Progress = 0; await progressBar.ProgressTo(1.0, 90000, Easing.Linear); 回答1: You can use a timer to increment the ProgressBar : var updateRate = 1000 / 30f; // 30Hz double step = updateRate / (2 * 30 * 1000f); Device.StartTimer(TimeSpan

问题 In the current stable version of node.js v0.10.33 there is a bug where setTimeout/setInterval does not fire anymore when setting the system time to the past. Run this code to see what I mean: var i = 0; var handle = setInterval(function() { console.log(++i); }, 1000); Then while it's running change the time of your system to the past, does not matter if on windows or linux. The interval / timeout will not fire anymore. When chaning the time to the future, node behaves perfectly fine and keeps

问题 I am trying to use android.os.CountDownTimer to literally show a countdown timer via a textview for fitness purposes. The issue I am having is the timer seems to be having trouble running on the main thread i.e. the countdown will jump 2-4 secs and is clearly being "lagged" - the timer is intended to be in an endless loop until a stop button is pressed. I am new to Java and Android and cannot figure out how to get the countdown timer running and updating the UI without any conflicts or

问题 I am trying to use android.os.CountDownTimer to literally show a countdown timer via a textview for fitness purposes. The issue I am having is the timer seems to be having trouble running on the main thread i.e. the countdown will jump 2-4 secs and is clearly being "lagged" - the timer is intended to be in an endless loop until a stop button is pressed. I am new to Java and Android and cannot figure out how to get the countdown timer running and updating the UI without any conflicts or

问题 I can't get the timer to fire once a minute on the minue, 1:00, 1:01, 1:02 etc. Instead, when the timer executes drifts by a couple of seconds each iteration internal void StartTimer() { DateTime nowEastern = CalendarEntity.Calendar.GetEasternTime(); int secondsInterval = 5; double additionalSeconds = secondsInterval - nowEastern.TimeOfDay.TotalSeconds % secondsInterval; if (additionalSeconds == 0) { additionalSeconds = 1; } var nearestOnOneMinutes = new DateTime( nowEastern.Year, nowEastern

问题 I was using the system timer (clock() function, see time.h) to time some serial and USB comms. All I needed was approx 1ms accurace. The first thing I noticed is that individual times can be out (plus or minus) 10ms. Timing a number of smaller events led to less accurate timing as events went by. Aggregate timing was slightly better. After a bit of a root on MSDN etc I stumbled across the timer in windows multi-media library (timeGetTime(), see MMSystem.h). This was much better with decent

问题 I need to create a Timer to update the UI at regular intervals. But the Swing Timer class is not available on Android. How can I work around this problem ? (I would avoid creating threads and then use the Timer class from java.util package) 回答1: You could use a Handler and the postAtTime() method or the postDelayed() method. This will allow you to schedule a Runnable to be executed at some point in the future. 回答2: Well, for your problem Handler class would suffice(+1 to Dave :)). FYI, there

问题 I'm using a pthread to schedule some tasks on my application. I copied the code from my old C version of the same application and it worked perfectly. Now I'm coding with C++ and it doesn't work anymore (basically it doesn't trigger the sigevent executing the given function). All creation and starting functions exit with rc 0, even when i use the timer_gettime. I simplified a lot the code to narrow down the issue but I could't find it yet: #include <signal.h> #include <time.h> int main (void)

问题 I'm programming in VB6 because we are using legacy code and hardware (external electronics). My programs are build around timers where I would use tasks in OS programming. The timers are running until their job is done. A flag is set and another timer is started. I want a supervisory timer that controllers the other timers When the timers produce no result or are waiting for a real world event that never comes (Do while loop) I want to kill the timer. In electronics we have a 'watch dog timer