I have tried binding the the ItemsControl and the canvas but it doesn't set them.

MainWindows.xaml

<Window xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:vm="clr-namespace:CanvasTesting.ViewModels;assembly=CanvasTesting"
        Icon="resm:CanvasTesting.Assets.avalonia-logo.ico"
        Title="CanvasTesting"
        Width="400"
        Height="500">

    <Design.DataContext>
        <vm:MainWindowViewModel/>
    </Design.DataContext>
    <DockPanel>
        <Grid DockPanel.Dock="Top">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="auto"/>
                <ColumnDefinition Width="83*"/>
                <ColumnDefinition Width="7*"/>
            </Grid.ColumnDefinitions>
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto"/>
                <RowDefinition Height="Auto"/>
                <RowDefinition Height="Auto"/>
            </Grid.RowDefinitions>
            <TextBlock Grid.Row="0" Grid.Column="0">Sides</TextBlock>
            <Slider Grid.Row="0" Grid.Column="1" Orientation="Horizontal" Minimum="3" Maximum="30" Value="{Binding Sides}"/>
            <TextBox Grid.Row="0" Grid.Column="2" Text="{Binding Sides}"/>
            <TextBlock Grid.Row="1" Grid.Column="0">Radius</TextBlock>
            <Slider Grid.Row="1" Grid.Column="1" Orientation="Horizontal" Minimum="0" Maximum="300" Value="{Binding Radius}"/>
            <TextBox Grid.Row="1" Grid.Column="2" Text="{Binding Radius}"/>
            <TextBlock Grid.Row="2" Grid.Column="0">Angle</TextBlock>
            <Slider Grid.Row="2" Grid.Column="1" Orientation="Horizontal" Minimum="0" Maximum="360" Value="{Binding Angle}"/>
            <TextBox Grid.Row="2" Grid.Column="2" Text="{Binding Angle}"/>
        </Grid>
        <ItemsControl Items="{Binding Lines}" Height="{Binding CanvasHeight, Mode=OneWayToSource}" Width="{Binding CanvasWidth, Mode=OneWayToSource}">
            <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                    <Canvas />
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.DataTemplates>
                <DataTemplate>
                    <Line StartPoint="{Binding Start}" EndPoint="{Binding End}" Stroke="Silver" StrokeThickness="3"/>
                </DataTemplate>
            </ItemsControl.DataTemplates>
        </ItemsControl>
    </DockPanel>
</Window>