PieChart is a chart meant to visualise the proportions of several scalar values. A PieChart takes an IPieSeries that consists of several IPieSlices where each slice contains the scalar value being represented by that slice.
The following example shows how to use a PieChart to present my favourite bars
<metrolib:PieChart>
<metrolib:PieChart.Outline>
<Pen Thickness="1" Brush="Black" />
</metrolib:PieChart.Outline>
<metrolib:PieChart.ValueTemplate>
<DataTemplate>
<TextBlock Text="{Binding}" Foreground="White" />
</DataTemplate>
</metrolib:PieChart.ValueTemplate>
<metrolib:PieChart.Series>
<metrolib:PieSeries>
<metrolib:PieSeries.Slices>
<metrolib:PieSlice Label="McCain's" Value="26" DisplayedValue="26%" Outline="{StaticResource SliceOutline}" />
<metrolib:PieSlice Label="McLaren's" Value="30" DisplayedValue="30%" Outline="{StaticResource SliceOutline}" />
<metrolib:PieSlice Label="White House Tavern" Value="14" DisplayedValue="14%" Outline="{StaticResource SliceOutline}" />
<metrolib:PieSlice Label="King Cola Bar" Value="3" DisplayedValue="3%" Outline="{StaticResource SliceOutline}" />
<metrolib:PieSlice Label="P & C" Value="27" DisplayedValue="27%" Outline="{StaticResource SliceOutline}" />
<metrolib:PieSlice Label="Puzzles" Value="0" DisplayedValue="1%" Outline="{StaticResource SliceOutline}" />
</metrolib:PieSeries.Slices>
</metrolib:PieSeries>
</metrolib:PieChart.Series>
</metrolib:PieChart>