Chart databinding make things slow...

Hi there,

In a chart, I have AreaSeries which binding to DataPoints which is the ObservableCollection of the Point(it is a property in my view model):

<AreaSeries ItemsSource = {Binding DataPoints} .../>

But this DataPoints is changing over some condition, for exapmle, a button click to generate the new DataPoints. The function for doing this is:

void button_click()
{
    DataPoints.Clear();
    for( int i=0;i<500; i++)
    {
        DataPoints.Add(new Point(i, random.NextDouble() *100));
    }
}

This is simple enough, right. But it takes a long time to accomplish. But if we don't bind this DataPoints to the AreaSeries. then the speed is back to normal.

Can you tell me what is wrong here?

Thanks

Gordon

Hello Gordon

I currently have plans for optimizations that will greatly speed up this sort of dynamic data changes in the very near future.

While you're waiting for these optimizations, there is one thing that you could do to work around the bad performance. Rather than clearing the collection, create a new ObservableCollection, add the data points to this collection, and then set your DataPoints property to be this new collection. Something like this:

void button_click()
{
    ObservableCollection<Point> points = new ObservableCollection<Point>();
    for(int i = 0; i < 500; i++)
    {
        points.Add(new Point(i, random.NextDouble() * 100));
    }
    DataPoints = points;
}

Sorry for the inconvenience.

-Jason