WPF/Silverlight rendering blur effect in realtime - wpf

Question

In my WPF project I've done with clicking some UI element such stuff:
void vb1_click(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
DispatcherTimer dt = new DispatcherTimer();
dt.Interval = new TimeSpan(0, 0, 0, 0, 1000);
dt.Tick += new System.EventHandler(dt_Tick);
dt.Start();
}
void dt_Tick(object sender, System.EventArgs e)
{
for(int i = 0; i < 20; i++)
{
this.vb2_blur_eff.Radius = (double)i;
}
}
The main problem is: "I can't see the each step of blur-effect per second. The program is idling and when the process is complete it gives me the final step of bluring the UI element.
I don't want it, cause both program idling is looking ugly and I want actually see the rendered result at the each period.

Answer 1

The main problem that I see is that you are using a For loop to set your Blur Radius, so it sits there cranks it up to max then returns control to the dispatcher which then updates it. I would prefer to do it with a StoryBoard but you can do it using a Timer and have the Timer set the Radius on each tick, when it reaches maximum then stop. You can use the Timer's interval to control the speed of the diffusion. I am using a Class level variable called count.
void vb1_click(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
DispatcherTimer dt = new DispatcherTimer();
dt.Interval = new TimeSpan(0, 0, 0, 0, 20);
dt.Tick += new System.EventHandler(dt_Tick);
count = 0;
dt.Start();
}
void dt_Tick(object sender, System.EventArgs e)
{
DispatcherTimer tmr = (DispatcherTimer)sender;
this.vb2_blur_eff.Radius = (double)count;
if (count == 20)
{
tmr.Stop();
tmr.Tick -= new System.EventHandler(dt_Tick);
}
count += 1;
}