Canvas with MinHeight and MinWidth
<Window x:Class="StackPanelDemo.Canvas2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="StackPanelDemo" Height="300" Width="300">
<Grid>
<Canvas MinHeight="50" MinWidth="50" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Grid.Column="0" Grid.ColumnSpan="1" Grid.Row="0" Grid.RowSpan="1" Margin="7,8,15,21" Width="NaN" Height="NaN" Name="canvas1">
<Label Canvas.Left="12" Canvas.Top="8" Name="label1">Top Left</Label>
<Label Canvas.Left="NaN" Canvas.Top="NaN" Name="label2" Canvas.Bottom="20" Canvas.Right="20">Bottom Right</Label>
</Canvas>
</Grid>
</Window>
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