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Silverlight 3 - data binding The position of the rectangle on the canvas

I'm currently trying to snap a collection of objects to a canvas in Silverlight 3 using the ItemsControl element, as shown below:

<ItemsControl x:Name="ctrl" ItemsSource="{Binding myObjectsCollection}">
    <ItemsControl.ItemsPanel>
        <ItemsPanelTemplate>
            <Canvas></Canvas>
        </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <Rectangle Stroke="LightGray" Fill="Black"  StrokeThickness="2" 
                   RadiusX="15" RadiusY="15" Canvas.Left="{Binding XAxis}"
                   Height="25" Width="25">
            </Rectangle>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

Unfortunately, it seems that binding to Canvas.Left is ignored. From what I learned here , it seems that this is due to the fact that the elements are placed inside the media presenter, and not the actual canvas that I specified in the panel elements.

Can I use data binding to determine the position of elements on a canvas?

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5 answers

, , , , - ItemsControl PrepareContainerForItemOverride. .

public class CustomItemsCollection
    : ItemsControl
{
    protected override void PrepareContainerForItemOverride(DependencyObject element, object item)
    {

        FrameworkElement contentitem = element as FrameworkElement;
        Binding leftBinding = new Binding("Left"); // "Left" is the property path that you want to bind the value to.
        contentitem.SetBinding(Canvas.LeftProperty, leftBinding);

        base.PrepareContainerForItemOverride(element, item);
    }

}
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ItemsControl.ItemContainerStyle Silverlight. . , ListBox.

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, ContentPresenter Canvas Rectangle. Canvas.Left:

<Rectangle Stroke="LightGray" Fill="Black" StrokeThickness="2" 
      RadiusX="15" RadiusY="15" Height="25" Width="25">
    <Rectangle.Margin>
        <Thickness Left="{Binding XAxis}"/>
    </Rectangle.Margin>
</Rectangle>
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, , - - ;

<ItemsControl ItemsSource="{Binding Notes}">
    <ItemsControl.ItemsPanel>
        <ItemsPanelTemplate>
            <Canvas Background="Aqua"/>
        </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>

    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <Border Width="{Binding W}" Height="{Binding H}" BorderBrush="Navy" BorderThickness="5" CornerRadius="10">
                <TextBlock Text="{Binding Text}"/>
                <Border.RenderTransform>
                    <TransformGroup>
                        <RotateTransform Angle="0"/>
                        <TranslateTransform X="{Binding X}" Y="{Binding Y}"/>
                    </TransformGroup>
                </Border.RenderTransform>
            </Border>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>
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Add the following to your ItemsControl:

 <ItemsControl.ItemContainerStyle>
    <Style TargetType="{x:Type ContentPresenter}">
      <Setter Property="Canvas.Left" Value="{Binding XPath=XAxis}"/>
    </Style>
  </ItemsControl.ItemContainerStyle>

No need for any custom controls

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