I am creating a little quiz and need to test how fast someone will do it. I would like the timer to start at 0 and then to count up from there so that the user can see how fast they are completing this said quiz.
I have the following code:
using System.Windows.Threading;
DispatcherTimer QuizTimer;
QuizTimer = new DispatcherTimer();
QuizTimer.Interval = new TimeSpan(0, 0, 1);
QuizTimer.Tick += new EventHandler(QuizTimer_Tick);
private void QuizTimer_Tick(object sender, EventArgs e)
{
lblQuizTimer.Content = DateTime.Now.ToString("mm:ss");
}
After searching the internet I haven't found any examples of where the dispatch timer is set to 0 and counts up. I understand that DateTime.Now means it's using the time that it is on computer right now and counting from there, but there are no other options that I have been able to see.
Just store the DateTime when the timer is started:
private DateTime startTime;
...
startTime = DateTime.Now;
QuizTimer.Start();
and subtract it from the current time to get a TimeSpan:
private void QuizTimer_Tick(object sender, EventArgs e)
{
lblQuizTimer.Content = (DateTime.Now - startTime).ToString(#"mm\:ss");
}
As a note, in WPF you would usually use a TextBlock instead of a Label to display some text:
tbQuizTimer.Text = (DateTime.Now - startTime).ToString(#"mm\:ss");
private readonly Stopwatch stopwatch = new Stopwatch();
...
stopwatch.Start();
private void QuizTimer_Tick(object sender, EventArgs e)
{
lblQuizTimer.Content = stopwatch.Elapsed.ToString(#"mm\:ss");
}
The Stopwatch class allows you to Stop and Start and that would make this scenario a bit easier.
Related
I am new to C# and also to WPF, I am trying to understand how DispatcherTimer works with GUI (WPF). I want to make my application run a function every 2 seconds but still using the app itself, when I try the following code, the timer starts but I can't use the following Buttons (logout and exit), it's like the app freezes.
public MainLoggedWindow()
{
Globals.mainLoggedWindow = this;
InitializeComponent();
DispatcherTimer dt = new DispatcherTimer();
dt.Tick += new EventHandler(dtTiker);
dt.Interval = new TimeSpan(0, 0, 1);
dt.Start();
}
private void exit_button_Click(object sender, RoutedEventArgs e)
{
logout_button_Click(sender, e);
Environment.Exit(-1);
}
private void logout_button_Click(object sender, RoutedEventArgs e)
{
Globals.LOGGED_IN_USER.logout();
this.Hide();
Globals.mainWindow.Show();
}
private int increment = 0;
private void dtTiker(object sender,EventArgs e)
{
increment++;
Time.Content = increment.ToString();
}
DispatcherTimer runs on the UI thread. It means that when the DispatcherTimer invokes its Tick method the UI thread becomes busy handling that, and it doesn't have time to handle other UI input like button clicks, so the window freezes.
What you could do is increase the interval time for your DispatcherTimer - your question desription says that it's once every two seconds, but your initialisation logic has it every one second: dt.Interval = new TimeSpan(0, 0, 1);
I have a windows form application with time input(in minutes) which fires a GUI application after the timer elapses. Initially I take the input from the user and set the time. Say, the user enters 45 mins. After 45 mins, my other GUI application is launched. Currently I'm using this:
Timer MyTimer = new Timer();
private void Form1_Load(object sender, EventArgs e)
{
MyTimer.Interval = 45mins // Input from user
MyTimer.Tick += new EventHandler(MyTimer_Tick);
MyTimer.Start();
}
private void MyTimer_Tick(object sender, EventArgs e)
{
//pop my GUI application
}
so now, my question is, how can i extended the timer? Suppose while counting down in the 20th Minute, the user wishes to extend 15mins of the timer, i take the input as 15 from the user and after that, the timer should add this 15 mins to the existing time and fire the GUI app after 35mins. i.e, it should count from 35mins.In total after the time elapses, it would have been 50mins. How can I achieve this?
Actually setting the timer to 1 second is just fine. there will be no performance hit. just keep track of the DateTime when it started, then you can use the tick event to display the elapsed time and check if that duration is greater than what the user wants
private DateTime timerStart;
private TimeSpan duration;
private void Form1_Load(object sender, EventArgs e)
{
Timer MyTimer = new Timer();
MyTimer.Interval = 1000; // tick at one second to update the UI
MyTimer.Tick += new EventHandler(MyTimer_Tick);
duration = whatever...// Input from user
timerStart = DateTime.Now;
MyTimer.Start();
}
private void changeTimer(TimeSpan newValue) {
duration = newValue;
}
private void MyTimer_Tick(object sender, EventArgs e)
{
TimeSpan alreadyElapsed = DateTime.Now.Subtract(timerStart);
// update the UI here using the alreadyElapsed TimeSpan
if(alreadyElapsed > duration)
{
//pop my GUI application
}
}
That's easy to implement if you set your timer to a one second/minute interval and another variable to the number of seconds/minutes.
Decrease the variable value on each timer tick. Add to that variable if you need to expand the interval. If the variable value is 0,launch the other application.
Currently developing a simple windows phone 8.1 silverlight app with an implemented countdown time. I have it working where I can input a set amount of minutes and it countdowns fine but what I am wanting to happen is for a user to input an amount of minutes and to countdown in seconds from there, for example it is currently 10, 9, 8, 7, 6, 5 when 10 seconds is input.
What I want to happen is that the user inputs 5 and it counts down like so:
4:59
4:58
4:57
This is my current code:
timer = new DispatcherTimer();
timer.Interval = new TimeSpan(0, 0, 1);
timer.Tick += timer_Tick;
basetime = Convert.ToInt32(tbxTime.Text);;
tbxTime.Text = basetime.ToString();
timer.Start();
}
void timer_Tick(object sender, object e)
{
basetime = basetime - 1;
tbxTime.Text = basetime.ToString();
if (basetime == 0)
{
timer.Stop();
}
You can keep most of your existing code if you just make basetime a TimeSpan instead of an int. It's easy to set its value from Minutes or Seconds via the appropriate static method.
var basetime = TimeSpan.FromMinutes(5);
Then you can subtract one second from it like this:
basetime -= TimeSpan.FromSeconds(1);
And display it like this:
tbxTime.Text = basetime.ToString(#"m\:ss");
Finally, comparing it to zero is also trivial:
if (basetime <= TimeSpan.Zero)
See Custom TimeSpan Format Strings for more display options.
I think you can just make use of suitable formatting of TimeSpan class (you will surely find many examples on SO). The easy example can look like this (I assume that you have a TextBox where you enter time and TextBlock which shows counter);
DispatcherTimer timer = new DispatcherTimer() { Interval = TimeSpan.FromSeconds(1) };
TimeSpan time;
public MainPage()
{
this.InitializeComponent();
timer.Tick += (sender, e) =>
{
time -= TimeSpan.FromSeconds(1);
if (time <= TimeSpan.Zero) timer.Stop();
myTextBlock.Text = time.ToString(#"mm\:ss");
};
}
private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
{ time = TimeSpan.FromMinutes(int.Parse((sender as TextBox).Text)); }
private void startBtn_Click(object sender, RoutedEventArgs e)
{ timer.Start(); }
Note that this is a very simple example. You should also think if DispatcherTimer is a good idea - it works on dispatcher, so in case you have some big job running on main UI thread it may not count the time properly. In this case you may think of using different timer, for example System.Threading.Timer, this runs on separate thread, so you will have to update your UI through Dispatcher.
I am writing a program to send SMS every 5 minutes. I want to stop this when the system time is 6 PM. How can I do that? This is my current code.
I want to modify this according to my above requirement.
while (true)
{
sms.SendSMS();
Thread.Sleep(30000);
}}).Start();
}
Generally never use Sleep is bad idea , use timer instead:
System.Timers.Timer SendSMS = new System.Timers.Timer();
SendSMS.Interval = 300000; ///300000ms=5min
SendSMS.Elapsed += new System.Timers.ElapsedEventHandler(SendSMS_Elapsed);
SendSMS.Enabled=true;
void SendSMS_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
sms.SendSMS();
}
Add a second timer to check the time and stop when is 6pm:
System.Timers.Timer StopSendSMS = new System.Timers.Timer();
StopSendSMS.Interval = 100;
StopSendSMS.Elapsed += new System.Timers.ElapsedEventHandler( StopSendSMS_Elapsed);
StopSendSMS.Enabled=true;
void StopSendSMS_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
if (int(DateTime.Now.Hour)==18))
{
SendSMS.Enabled=false;
StopSendSMS.Enabled=false; ///no need to check anymore
}
}
You can use the below condition to check system TIME.
`if(DateTime.Now.Hour.ToString("HH") == "18") //Hour is in 24hour format`
When the user does something (touch on a StackPanel, in this case), I need to begin a timer of some sort (probably DispatcherTimer as I'm working in WPF) and if another touch happens again within a certain amount of time then I'll call a method. As you can probably guess - this is to implement a double-tap functionality.
I'm assuming the best way to achieve this is through using threads (i.e. a child thread to increment a timespan which can be checked by the Main thread any time the StackPanel is touched again?)
Thanks,
Dan
You do not need to start another thread to do this.
Just take a timestamp of when the first tap happened and use this. You can then calculate the timespan by subtracting this time from the current time:
private DateTime _lastTap;
public void TapHandler()
{
DateTime now = DateTime.UtcNow;
TimeSpan span = now - lastTap;
_lastTap = now;
if (span < TimeSpan.FromSeconds(1)) {...}
}
Alternatively, as suggested by #DannyVarod, you can use a Stopwatch to achieve the same result (but with more accurate timing):
private Stopwatch _stopwatch = new Stopwatch();
public void TapHandler()
{
TimeSpan elapsed = _stopwatch.Elapsed;
_stopwatch.Restart();
if (elapsed < TimeSpan.FromSeconds(1)) {...}
}
The best way is to stick with DispatcherTimer as you first pointed out, as this will ensure you don't need to do any thread marshalling on tick. If you explictly need accuracy and/or background threads, please see the System.Timers.Timer class and System.Threading.Timer class.
A code example which allows differentiation between Single and Double clicks can be found on MSDN (Windows Forms specific, however the principle is the same). Alternatively, please see this example using DispatcherTimer taken from this previous question
private static DispatcherTimer clickTimer =
new DispatcherTimer(
TimeSpan.FromMilliseconds(SystemInformation.DoubleClickTime),
DispatcherPriority.Background,
mouseWaitTimer_Tick,
Dispatcher.CurrentDispatcher);
private void Button_MouseDoubleClick(object sender, MouseButtonEventArgs e)
{
// Stop the timer from ticking.
myClickWaitTimer.Stop();
Trace.WriteLine("Double Click");
e.Handled = true;
}
private void Button_Click(object sender, RoutedEventArgs e)
{
myClickWaitTimer.Start();
}
private static void mouseWaitTimer_Tick(object sender, EventArgs e)
{
myClickWaitTimer.Stop();
// Handle Single Click Actions
Trace.WriteLine("Single Click");
}