How to set fixed window size for Universal Windows Application

Question

I just started to develop an Universal Windows Application in VS2015 Community Edition. I have used the sample called PieCharts for Windows UWP.

My problem is that

Answer 1

I found a solution. I think its not the best, but it works.
XAML:

c#

    private void FormName_SizeChanged(object sender, SizeChangedEventArgs e)
    {

        ApplicationView.GetForCurrentView().TryResizeView(new Size(900, 600));
    }

Hope it helps