Question

Why does this work so well in wpf

<ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto">
<Canvas x:Name="MyDesigner">
</Canvas>
</ScrollViewer>

Now when I do the same thing in silverlight and load an control “that can be dragged” the scrollbars are not triggered, when I drag out of view, nothing happens… but in wpf it automatically shows them…

Answer 1

Here is the solution I found.
The canvas can grow dynamically, but you will need to explicitly set the height to a new value.
So, if you have 20 textblocks with a height of 21, you need to set the canvas height as:
Canvas.Height = 22.0 * 100;
for the scrollviewer to pick up the new height.

MainPage.xaml

<Canvas Canvas.Left="5" Canvas.Top="25"  >
    <ScrollViewer Width="300" Height="700"  x:Name="CanSummaryScroller">
        <Canvas x:Name="canSummaryCells"  >
        </Canvas>
    </ScrollViewer>  
</Canvas>

MainPage.xaml.cs

boxDevSumList is a List of TextBoxes

for (int i = 0; i < 100; i++)
{
    boxDevSumList.Add(new Cell());
    (boxDevSumList.ElementAt(i)).Width = 271;
    (boxDevSumList.ElementAt(i)).Height = 21;
    (boxDevSumList.ElementAt(i)).SetValue(FontFamilyProperty, new FontFamily("Calibri"));
    (boxDevSumList.ElementAt(i)).FontSize = 12;
    (boxDevSumList.ElementAt(i)).Text = "this is a test";
    if (i.Equals(1) || i.Equals(3) || i.Equals(5) || i.Equals(7) || i.Equals(9))
        (boxDevSumList.ElementAt(i)).Background = lgBrush;
    (boxDevSumList.ElementAt(i)).Opacity = .9;
    canSummaryCells.Children.Add(boxDevSumList.ElementAt(i));
    boxDevSumList.ElementAt(i).SetValue(Canvas.TopProperty, (double)(i * 21) + 45);
    boxDevSumList.ElementAt(i).SetValue(Canvas.LeftProperty, 4.0);
    canSummaryCells.Height = 22.0 * 100;
}