C# 如何防止具有图像元素的ListBoxItem拉伸或扩展？

我有一个列表框，它的ItemsPanel有一个网格。我有几个ListBoxItems，并与Grid.Column/Row一起使用，以便在网格中正确定位它们。我在每个ListBoxItem中放置了一个图像元素。每个图像元素都有一个256x256 PNG文件作为其源

当我运行应用程序时，每个ListBoxItems都伸展到了所有地方，ListBox变得异常巨大。我不知道为什么会这样。如何防止ListBoxItems拉伸/扩展，使其大小适合ListBoxItems的父元素

我尝试了StretchDirection Down（向下拉伸方向），只对每个图像进行了拉伸，但所有图像仍然拉伸。这是我的XAML

<Grid>
    <ListBox Margin="10"
                BorderThickness="0"
                Focusable="True">

        <ListBox.ItemsPanel>
            <ItemsPanelTemplate>
                <Grid IsItemsHost="True">
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="*" />
                        <ColumnDefinition Width="*" />
                        <ColumnDefinition Width="*" />
                        <ColumnDefinition Width="*" />
                    </Grid.ColumnDefinitions>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="*" />
                        <RowDefinition Height="*" />
                        <RowDefinition Height="*" />
                        <RowDefinition Height="*" />
                    </Grid.RowDefinitions>
                </Grid>
            </ItemsPanelTemplate>
        </ListBox.ItemsPanel>


        <ListBoxItem Grid.Column="0"
                         Grid.Row="0"
                         Grid.ColumnSpan="3"
                         Grid.RowSpan="3">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>
        <ListBoxItem Grid.Column="3"
                         Grid.Row="0">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>
        <ListBoxItem Grid.Column="3"
                         Grid.Row="1">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>
        <ListBoxItem Grid.Column="3"
                         Grid.Row="2">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>
        <ListBoxItem Grid.Column="0"
                         Grid.Row="3">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>
        <ListBoxItem Grid.Column="1"
                         Grid.Row="3">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>
        <ListBoxItem Grid.Column="2"
                         Grid.Row="3">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem> />
        <ListBoxItem Grid.Column="3"
                         Grid.Row="3">
            <Image Source="CCTV.png"
                     RenderOptions.BitmapScalingMode="HighQuality"
                     Stretch="Uniform"
                     StretchDirection="DownOnly" />
        </ListBoxItem>

    </ListBox>

</Grid>

/>

编辑

---

需要限制图像的大小，如下所示：

<Image Source="{StaticResource Delete}" Width="16" Height="16" />

Set ColumnDefinition Width=“256”如果它们具有固定的宽度和高度