Connecting ScatterViewItems with a line

I want to draw lines between ScatterViewItems but it doesn't work with what I already found here. There is a Line, but not connected to the center of the ellipses. Does anybody see my mistake? Here is what I have:

 <Grid>
    <s:ScatterView>
        <s:ScatterViewItem Height="250" Width="500" Background="Transparent" Orientation="0" HorizontalAlignment="Right" Margin="0,70,-764,-70" d:LayoutOverrides="HorizontalAlignment, Width">
            <s:ScatterView Height="250" Width="500" Background="BlueViolet">
                <s:ScatterViewItem Background="Transparent" Center="100,145" Orientation="0">
                    <Label Content="Knoten A" Background="WhiteSmoke" Foreground="Black"/>
                </s:ScatterViewItem>
                <s:ScatterViewItem x:Name="StartItem" CanMove="False" CanRotate="False" Margin="0" Center="10,125" Background="Transparent">
                    <Ellipse Width="10" Height="10" Fill="Transparent" Stroke="Black" Margin="0,0,0,0"/>
                </s:ScatterViewItem>
                <s:ScatterViewItem x:Name="EndItem" CanMove="False" CanRotate="False" Margin="0" Center="490,125" Background="Transparent">
                    <Ellipse Width="10" Height="10" Fill="Transparent" Stroke="Black" Margin="0,0,0,0"/>
                </s:ScatterViewItem>
                <s:ScatterViewItem Background="Transparent">
                    <Canvas Name="LineHost"/>
                </s:ScatterViewItem>
            </s:ScatterView>
        </s:ScatterViewItem>
    </s:ScatterView>
</Grid>

And the c#

 Line line = new Line { Stroke = Brushes.Black, StrokeThickness = 2.0 };
        BindLineToScatterViewItems(line, StartItem, EndItem);
        LineHost.Children.Add(line);

private void BindLineToScatterViewItems(Line line, ScatterViewItem StartItem, ScatterViewItem EndItem)
    {
        BindingOperations.SetBinding(line, Line.X1Property,
                                     new Binding {Source = StartItem, Path = new PropertyPath("ActualCenter.X")});
        BindingOperations.SetBinding(line, Line.Y1Property,
                                     new Binding { Source = StartItem, Path = new PropertyPath("ActualCenter.Y") });

        BindingOperations.SetBinding(line, Line.X2Property,
                                    new Binding { Source = EndItem, Path = new PropertyPath("ActualCenter.X") });
        BindingOperations.SetBinding(line, Line.Y2Property,
                                     new Binding { Source = EndItem, Path = new PropertyPath("ActualCenter.Y") });
    }

回答1:

The startpoint AND endpoint from your lines is ActualCenter.X/ActualCenter.Y of your Startitem. If the ActualCenter of your Startitem is 10/100, you would draw a line from 10/100 to 10/100, which is a reason why youre not seeing any line. Instead of setting Source = Startitem in the last two lines of your BindLineToScatterViewItems method, try setting Source = EndItem.

Hope this helps.

回答2:

If I use Canvas instead of ScatterView and ScatterViewItem and the order ist like this

 <s:ScatterView>
        <Canvas Name="LineCanvas2" Width="500" Height="250" Background="Aquamarine">
            <Canvas Background="Transparent" Name="LineCanvas"/>
            <s:ScatterView Width="500" Height="250" Background="Transparent">
                <s:ScatterViewItem ...

there is no problem with the positioning of the connection lines.