Question: I have a ListView that its ItemsPanelTemplate is a Canvas, and every item is a rectangle.
I'm trying to draw a Rectangle outside the Canvas in the position of (-50,-50) with no successive. can I do that somehow ?

![enter image description here](https://i.stack.imgur.com/rJ4Ns.png)

The XAML:

```
<Grid >
    <ListView BorderThickness="0" BorderBrush="Transparent" ItemsSource="{Binding Rectangles}" Height="200" Width="200">
        <ListView.Resources>
            <Style TargetType="{x:Type ListViewItem}">
                <Setter Property="Canvas.Left" Value="{Binding Left, Mode=TwoWay}" />
                <Setter Property="Canvas.Top"  Value="{Binding Top, Mode=TwoWay}" />
            </Style>
        </ListView.Resources>
        <ListView.ItemTemplate>
            <DataTemplate DataType="{x:Type WpfApplication2:RectangleModel}">
                <Rectangle Width="30" Height="30"  Canvas.Left="{Binding Left}" Canvas.Right="{Binding Right}" Fill="LightCoral"
                           ClipToBounds="False"/>
            </DataTemplate>
        </ListView.ItemTemplate>

        <ListView.ItemsPanel>
            <ItemsPanelTemplate>
                <Canvas Background="LightBlue"/>
            </ItemsPanelTemplate>
        </ListView.ItemsPanel>
    </ListView>
</Grid>

```

Code behind:

```
 public partial class MainWindow : Window
{
    public List<RectangleModel> Rectangles { get; set; }

    public MainWindow()
    {
        Rectangles = new List<RectangleModel>();
        Rectangles.Add(new RectangleModel { Left = -50, Top = -50 });
        Rectangles.Add(new RectangleModel { Left = 0, Top = 0 });
        Rectangles.Add(new RectangleModel { Left = 50, Top = 50 });
        DataContext = this;
        InitializeComponent();
    }
}

```

Answer: 
I may be wrong, but this seems to be rather simple problem (I may have completely assumed the wrong thing, but I'm not sure so I'm going with the assumption just in case).

You've defined your `ListView` to be 200 by 200 and your `Canvas` is taking all that space. Judging by your picture, I feel it is `Canvas` that you want to be of 200 by 200 not the `ListView`.

**Xaml:**

```
<Grid >
        <ListView BorderThickness="0" BorderBrush="Transparent" ItemsSource="{Binding Rectangles}">
            <ListView.Resources>
                <Style TargetType="{x:Type ListViewItem}">
                    <Setter Property="Canvas.Left" Value="{Binding Left, Mode=TwoWay}" />
                    <Setter Property="Canvas.Top"  Value="{Binding Top, Mode=TwoWay}" />
                </Style>
            </ListView.Resources>
            <ListView.ItemTemplate>
                <DataTemplate DataType="{x:Type wpfApplication1:RectangleModel}">
                    <Rectangle Width="30" Height="10"  Canvas.Left="{Binding Left}" Canvas.Top="{Binding Top}" Fill="LightCoral"
                           ClipToBounds="False"/>
                </DataTemplate>
            </ListView.ItemTemplate>

            <ListView.ItemsPanel>
                <ItemsPanelTemplate>
                    <Canvas Background="LightBlue" ClipToBounds="False" Height="200" Width="200"/>
                </ItemsPanelTemplate>
            </ListView.ItemsPanel>
        </ListView>
    </Grid>

```

**Result:**

![enter image description here](https://i.stack.imgur.com/dLaiS.png)
I did it via Popup, it looks well but I dont know whether it fits in your requirement or not

```
<Grid  Background="Transparent">
    <ListView BorderThickness="0" BorderBrush="Transparent" ItemsSource="{Binding Rectangles}" Height="200" Width="200">
        <ListView.Resources>
            <Style TargetType="{x:Type ListViewItem}">
                <Setter Property="Canvas.Left" Value="{Binding Left, Mode=TwoWay}" />
                <Setter Property="Canvas.Top"  Value="{Binding Top, Mode=TwoWay}" />
            </Style>
        </ListView.Resources>
        <ListView.ItemTemplate>
            <DataTemplate DataType="{x:Type WpfApplication2:RectangleModel}">
                <Popup Width="30" Height="30"  Canvas.Left="{Binding Left}" Canvas.Right="{Binding Right}" 
                       IsOpen="True"
                       ClipToBounds="False">
                    <Rectangle Fill="LightCoral"/>
                </Popup>
            </DataTemplate>
        </ListView.ItemTemplate>

        <ListView.ItemsPanel>
            <ItemsPanelTemplate>
                <Canvas Background="LightBlue"/>
            </ItemsPanelTemplate>
        </ListView.ItemsPanel>
    </ListView>
</Grid>

```

This gives same result as you want. But you need to work more on that like their relative positions and all.