I need to stop the event connected to the Dispatcher after the event first time tick.
Any idea how to do it.
int closeSeconds = Convert.ToInt32(utility.GetConfiguration("device", "closePopupPrinterAfterSeconds"));
var dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
dispatcherTimer.Tick += new EventHandler(dispatcherTimerCheckPopupPrinter_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, closeSeconds);
dispatcherTimer.Start();
private void dispatcherTimerCheckPopupPrinter_Tick(object sender, EventArgs e)
{
// stop the dispatcherTimer here, so this method will not fire every x seconds
System.Windows.Threading.Dispatcher displatcher = (System.Windows.Threading.Dispatcher)sender;
}
Cast the sender argument to DispatcherTimer, not Dispatcher, and call its Stop method, or set its IsEnabled property to false.
private void dispatcherTimerCheckPopupPrinter_Tick(object sender, EventArgs e)
{
var timer = (DispatcherTimer)sender; // not Dispatcher!
timer.Stop(); // or timer.IsEnabled = false;
}
Related
I'm trying to hold down mouse event using PreviewMouseDown and DispatcherTimer as following:
private void button_PreviewMouseDown(object sender, MouseButtonEventArgs e)
{
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 1);
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
_sec = _sec + 1;
if (_sec == 3)
{
dispatcherTimer.Stop();
MessageBox.Show(_sec.ToString());
_sec = 0;
return;
}
}
This code works, BUT the first mouse down takes 3 seconds to display the message, after that the time to show the message is decreased (less that 3 seconds)
You don't need a DispatcherTimer to do this. You could handle the PreviewMouseDown and the PreviewMouseUp events.
Please refer to the following sample code.
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
PreviewMouseDown += Window3_PreviewMouseDown;
PreviewMouseUp += Window3_PreviewMouseUp;
}
DateTime mouseDown;
private void Window3_PreviewMouseDown(object sender, MouseButtonEventArgs e)
{
mouseDown = DateTime.Now;
}
readonly TimeSpan interval = TimeSpan.FromSeconds(3);
private void Window3_PreviewMouseUp(object sender, MouseButtonEventArgs e)
{
if (DateTime.Now.Subtract(mouseDown) > interval)
MessageBox.Show("Mouse was held down for > 3 seconds!");
mouseDown = DateTime.Now;
}
}
The second time this gets called
dispatcherTimer.Tick += dispatcherTimer_Tick; // try without that new EventHandler(...)
a second handled will be attached. So, after the first second, sec will be 2, since the event is called twice.
You can try to dispose and set to null the dispatcherTimer variable on the PreviewMouseUp & create a new instance on the PreviewMouseDown.
Or another option would be, on the PreviewMouseUp, you can
dispatcherTimer.Tick -= dispatcherTimer_Tick;
sec = 0;
-= will detach the event handler.
I need to create a application which must have a timer control;
the timer must automatically initialize when each form is called, when the time reach 3 seconds means it must load the another form.
I have tried this:
private void Form1_Load(object sender, EventArgs e)
{
timer1.Start();
if (timer1.Interval = 3000)
{
MessageBox.Show("Times up");
form2 i=new form2();
form2.show();
}
}
but I cant get the correct result....
Timers in C# work by firing events periodically. You need to attach an event handler which responds to the timer event. The MSDN documentation has a straightforward example (code snippet reproduced below).
public Timer aTimer;
public static void Main()
{
// Create a timer with a ten second interval.
aTimer = new System.Timers.Timer(10000);
// Hook up the Elapsed event for the timer.
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
// Set the Interval to 2 seconds (2000 milliseconds).
aTimer.Interval = 2000;
aTimer.Enabled = true;
Console.WriteLine("Press the Enter key to exit the program.");
Console.ReadLine();
}
// Specify what you want to happen when the Elapsed event is
// raised.
private static void OnTimedEvent(object source, ElapsedEventArgs e)
{
Console.WriteLine("The Elapsed event was raised at {0}", e.SignalTime);
}
initialize and enable your timer and attach an event handler to Tick event.
Timer timer;
private void Form1_Load(object sender, EventArgs e)
{
timer = new Timer();
timer.Enabled = true;
timer.Interval = 3000;
timer.Tick += timer_Tick;
timer.Start();
}
private void timer_Tick(object sender, EventArgs e)
{
MessageBox.Show("Times up");
Form2 i = new Form2();
i.Show();
}
I wish to execute a function at an interval of 1 or so minutes. How can I achieve this in Windows Phone 8. I am not looking for background agents. The app will be running in the foreground. What are my options?
you can use the DispatcherTimer Class
private DispatcherTimer dispatcherTimer;
// Constructor
public MainPage()
{
InitializeComponent();
dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 1);
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
//do whatever you want to do here
}
Refer: (http://msdn.microsoft.com/en-us/library/system.windows.threading.dispatchertimer(v=vs.110).aspx)
Try this
public void Start_timer()
{
DispatcherTimer timer = new DispatcherTimer();
timer.Tick += timer_Tick;
timer.Interval = new TimeSpan(00, 0, 10);
bool enabled = timer.IsEnabled;
timer.Start();
}
void timer_Tick(object sender, object e)
{
//function to execute
}
You can also use ThreadPoolTimer:
TimeSpan period = TimeSpan.FromSeconds(60);
ThreadPoolTimer PeriodicTimer = ThreadPoolTimer.CreatePeriodicTimer((source) =>
{
// TODO: Work
Deployment.Current.Dispatcher.BeginInvoke(() =>
{
// UI update
});
}, period);
One option may be to use DispatcherTimer.
Simply register a callback on the Tick event.
I am a newbie in timer in wpf and I need a code that every 5mins there is a message box will pop up. .can anyone help me for the simple code of timer.
That's what I tried so far:
System.Windows.Threading.DispatcherTimer dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
private void test()
{
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 1);
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
// code goes here
}
private void button1_Click(object sender, RoutedEventArgs e)
{
test();
}
In WPF, you use a DispatcherTimer.
System.Windows.Threading.DispatcherTimer dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0,5,0);
dispatcherTimer.Start();
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
// code goes here
}
Adding to the above. You use the Dispatch timer if you want the tick events marshalled back to the UI thread. Otherwise I would use System.Timers.Timer.
Basically when we apply some interval ie 5 sec we have to wait for it.
Is it possible to apply interval and execute timer immediately and don't wait 5 sec?
(I mean the interval time).
Any clue?
Thanks!!
public partial class MainWindow : Window
{
DispatcherTimer timer = new DispatcherTimer();
public MainWindow()
{
InitializeComponent();
timer.Tick += new EventHandler(timer_Tick);
this.Loaded += new RoutedEventHandler(MainWindow_Loaded);
}
void timer_Tick(object sender, EventArgs e)
{
MessageBox.Show("!!!");
}
void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
timer.Interval = new TimeSpan(0, 0, 5);
timer.Start();
}
}
There are definitely more elegant solutions, but a hacky way is to just call the timer_Tick method after you set the interval initially. That'd be better than setting the interval on every tick.
Initially set the interval to zero and then raise it on a subsequent call.
void timer_Tick(object sender, EventArgs e)
{
((Timer)sender).Interval = new TimeSpan(0, 0, 5);
MessageBox.Show("!!!");
}
could try this:
timer.Tick += Timer_Tick;
timer.Interval = 0;
timer.Start();
//...
public void Timer_Tick(object sender, EventArgs e)
{
if (timer.Interval == 0) {
timer.Stop();
timer.Interval = SOME_INTERVAL;
timer.Start();
return;
}
//your timer action code here
}
Another way could be to use two event handlers (to avoid checking an "if" at every tick):
timer.Tick += Timer_TickInit;
timer.Interval = 0;
timer.Start();
//...
public void Timer_TickInit(object sender, EventArgs e)
{
timer.Stop();
timer.Interval = SOME_INTERVAL;
timer.Tick += Timer_Tick();
timer.Start();
}
public void Timer_Tick(object sender, EventArgs e)
{
//your timer action code here
}
However the cleaner way is what was already suggested:
timer.Tick += Timer_Tick;
timer.Interval = SOME_INTERVAL;
SomeAction();
timer.Start();
//...
public void Timer_Tick(object sender, EventArgs e)
{
SomeAction();
}
public void SomeAction(){
//...
}
That's how I solved it:
dispatcherTimer = new DispatcherTimer();
dispatcherTimer.Tick += new EventHandler(DispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 10);
dispatcherTimer.Start();
DispatcherTimer_Tick(dispatcherTimer, new EventArgs());
Works for me without any issues.
Disclaimer: This answer is not for the OP because he wants to use DispatcherTimer
But if you do not have this limitation and you can use another Timer, then there is a cleaner solution
You can use System.Threading.Timer
The most important thing is setting dueTime:0
System.Threading.Timer timer = new Timer(Callback, null, dueTime:0, period:10000);
The documentation of the dueTime is the following
The amount of time to delay before callback is invoked, in milliseconds. Specify Infinite to prevent the timer from starting. Specify zero (0) to start the timer immediately.
and your callback is like this
private void Callback(object? state) =>
{
}
Again this does not use DispatcherTimer but it could solve your problem
Related answer