How can i make a control sticky?

How can i make a control to be sticky? I have a scrollviewer and inside that a grid. Inside grid i have a button. The button is set to horizontal alignment - center and vertical alignment - bottom. Now, 开发者_如何转开发when the size of the grid increases the button is no more visible on the screen. I have to scroll to really see the button. Can i make the button to be sticky so that it is always there at the bottom of the screen?

Thanks in advance :)

Anything you put inside the scollviewer will be part of the scrollable content. You can either remove that control and put it outside the scrollviewer, or put inside a floating popup control.

Remove the button from inside the ScrollViewer:

<Grid>
   <ScrollViewer>
      //Content
   </ScrollViewer>
   <Button HorizontalAlignment="Center" VerticalAlignment="Bottom" />
</Grid>