Question

I’ve got a little problem using WPF Dispatcher Timer. On each timer tick my application freezes for a moment (until timer tick method finishes). This is my code:

private DispatcherTimer _Timer = new DispatcherTimer();

_Timer.Tick += new EventHandler(_DoLoop);
_Timer.Interval = TimeSpan.FromMilliseconds(1500);
_Timer.Start();

Is there any way to avoid this and have my application run smoothly?

Answer 1

This is expected. your _DoLoop is executed on the same thread as UI.

from DispatcherTimer Class MSDN

If a System.Timers.Timer is used in a
WPF application, it is worth noting
that the System.Timers.Timer runs on a
different thread then the user
interface (UI) thread. In order to
access objects on the user interface
(UI) thread, it is necessary to post
the operation onto the Dispatcher of
the user interface (UI) thread using
Invoke or BeginInvoke. Reasons for
using a DispatcherTimer opposed to a
System.Timers.Timer are that the
DispatcherTimer runs on the same
thread as the Dispatcher and a
DispatcherPriority can be set on the
DispatcherTimer.

If you need to execute time consuming computations run it on another thread to keep UI responsive.