Gewusst wie: Auslösen des ScrollChanged-Ereignisses
Beispiel
In diesem Beispiel wird dargestellt, wie das ScrollChanged-Ereignis eines ScrollViewer behandelt wird.
Ein FlowDocument-Element mit Paragraph-Teilen wird in XAML definiert. Wenn das ScrollChanged-Ereignis aufgrund der Benutzerinteraktion eintritt, wird ein Handler aufgerufen, und Text wird in einen TextBlock geschrieben, der angibt, dass das Ereignis eingetreten ist.
<ScrollViewer Name="sv1" CanContentScroll="False" ScrollChanged="sChanged">
<FlowDocument FontFamily="Arial" PageWidth="400">
<Paragraph>
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
</Paragraph>
...
<Paragraph>
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut
laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation
ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure.
</Paragraph>
</FlowDocument>
</ScrollViewer>
Private Sub sChanged(ByVal sender As Object, ByVal args As ScrollChangedEventArgs)
If (sv1.CanContentScroll = True) Then
tBlock1.Foreground = System.Windows.Media.Brushes.Red
tBlock1.Text = "ScrollChangedEvent just Occurred"
tBlock3.Text = "ExtentWidth is now " + args.ExtentWidth.ToString()
tBlock4.Text = "ExtentHeightChange was " + args.ExtentHeightChange.ToString()
tBlock5.Text = "ExtentWidthChange was " + args.ExtentWidthChange.ToString()
tBlock6.Text = "HorizontalOffset is now " + args.HorizontalOffset.ToString()
tBlock7.Text = "VerticalOffset is now " + args.VerticalOffset.ToString()
tBlock8.Text = "HorizontalChange was " + args.HorizontalChange.ToString()
tBlock9.Text = "VerticalChange was " + args.VerticalChange.ToString()
tBlock10.Text = "ViewportHeight is now " + args.ViewportHeight.ToString()
tBlock11.Text = "ViewportWidth is now " + args.ViewportWidth.ToString()
tBlock12.Text = "ViewportHeightChange was " + args.ViewportHeightChange.ToString()
tBlock13.Text = "ViewportWidthChange was " + args.ViewportWidthChange.ToString()
Else
tBlock1.Text = ""
End If
private void sChanged(object sender, ScrollChangedEventArgs e)
{
if (sv1.CanContentScroll == true)
{
tBlock1.Foreground = System.Windows.Media.Brushes.Red;
tBlock1.Text = "ScrollChangedEvent just Occurred";
tBlock2.Text = "ExtentHeight is now " + e.ExtentHeight.ToString();
tBlock3.Text = "ExtentWidth is now " + e.ExtentWidth.ToString();
tBlock4.Text = "ExtentHeightChange was " + e.ExtentHeightChange.ToString();
tBlock5.Text = "ExtentWidthChange was " + e.ExtentWidthChange.ToString();
tBlock6.Text = "HorizontalOffset is now " + e.HorizontalOffset.ToString();
tBlock7.Text = "VerticalOffset is now " + e.VerticalOffset.ToString();
tBlock8.Text = "HorizontalChange was " + e.HorizontalChange.ToString();
tBlock9.Text = "VerticalChange was " + e.VerticalChange.ToString();
tBlock10.Text = "ViewportHeight is now " + e.ViewportHeight.ToString();
tBlock11.Text = "ViewportWidth is now " + e.ViewportWidth.ToString();
tBlock12.Text = "ViewportHeightChange was " + e.ViewportHeightChange.ToString();
tBlock13.Text = "ViewportWidthChange was " + e.ViewportWidthChange.ToString();
}
else
{
tBlock1.Text = "";
}