How to organize elements inside a Button - wpf

Question

i'm new to wpf .
i got a wpf button ,
in it i need to place 2 elements a textblock and a viewbox encapsulating a canvas
the problem is i can't seem to see the canvas at all , unless i give it static values for its size
<Button Margin="10,30,10,10" Padding="0">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="2*"/>
</Grid.ColumnDefinitions>
<TextBlock Text="Me" Grid.Row="0" Grid.Column="0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"></TextBlock>
<Viewbox Margin="0,0,0,5">
<Canvas Background="red" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Grid.Row="0" Grid.Column="1" >
<Ellipse HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Stroke="Black" StrokeThickness="4" ></Ellipse>
</Canvas>
</Viewbox>
</Grid>
</Button>
iv'e also attempted this using a stack panel with an horizontal orintation
in any case the canvas does not show
any thoughts of what i'm doing wrong ?
thanks.

Answer 1

Attached Grid properties only work when at the Grid-child-level, i.e. the properties set on the canvas do not take effect they should be set on the container, the ViewBox which is a direct child of the Grid.
Viewboxes only work if the content has a concrete size, you probably need neither the ViewBox nor the Canvas. If you want the Ellipse to be a circle set Stretch="Uniform"
The contents of Buttons do not stretch by default you should set HorizontalContentAligment and its vertical counterpart to Stretch.
e.g.
<Button Margin="10,30,10,10" Padding="0" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*" />
<ColumnDefinition Width="2*" />
</Grid.ColumnDefinitions>
<TextBlock Text="Me" Grid.Row="0" Grid.Column="0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"></TextBlock>
<Ellipse Stretch="Uniform" Grid.Column="1" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
Stroke="Black" StrokeThickness="4"></Ellipse>
</Grid>
</Button>