How to extract individual x axis y axis values from a point to draw a line in WPF

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In ViewModel class, I have ObservableCollection<List<point>> MyList as property. in xaml, I need to extract x axis y axis values to draw lines from Mylist. I have already set DataContext to VM instance in xaml.

What I have tried:

<ScrollViewer Name="scrollViewer" HorizontalScrollBarVisibility="Auto"   Grid.Row="2" Grid.Column="3" 
                    Height= "600" Width="Auto">
            <ItemsControl ItemsSource="{Binding Path=MyList}">
                <ItemsControl.ItemsPanel>
                    <ItemsPanelTemplate>
                        <Canvas x:Name="front_canvas" Background="White"  Height="1200" Width="{Binding CanvasWidth}" />
                    </ItemsPanelTemplate>
                </ItemsControl.ItemsPanel>
                <ItemsControl.ItemTemplate>
                    <DataTemplate>
                        <Line X1="{Binding Path=LinePoints}" Y1="{Binding LinePoints}" 
                            X2="{Binding LinePoints}" Y2="{Binding LinePoints}"
                              Stroke="Black" StrokeThickness="1">
                        </Line>
                    </DataTemplate>
                </ItemsControl.ItemTemplate>
            </ItemsControl>
        </ScrollViewer>

Posted 19-Nov-18 1:24am

hamid18

Updated 19-Nov-18 6:12am

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josda1000 · Answer 1 · 2018-11-19T05:24:00

I found potential help for you on stackoverflow:
data binding - Bind collection of lines to canvas in WPF - Stack Overflow[^]

Looks like you didn't finish filling in the bindings for the points when drawing the line, at the least, and you may want to use its solution to create a custom Line to keep all of the data in a logical structure.

Kenneth Haugland · Answer 2 · 2018-11-19T06:12:00

The optimal solution depends on your problem, but I did things a little different since one nearly always want the Y axis inverted when plotting.
A simple WPF LineChart control[^]

HTML

<ItemsControl x:FieldModifier="private" x:Name="PlotArea" Canvas.Bottom="40" Canvas.Left="40"  ClipToBounds="True"  ItemsSource="{Binding}">
    <ItemsControl.ItemsPanel>
        <ItemsPanelTemplate>
            <Canvas >
                <Canvas.LayoutTransform>
                    <ScaleTransform ScaleX="1" ScaleY="-1"></ScaleTransform>
                </Canvas.LayoutTransform>
            </Canvas>
        </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>
</ItemsControl>

My problem was that the observable collection could not be bonded directly to the Points in the PolyLine. So I ended up writing some code that did this manually. Or you could do the approach that is already suggested.

How to extract individual x axis y axis values from a point to draw a line in WPF

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