Distribute Labels evenly in certain space [duplicate] - wpf

Question

I have an ItemsControl, the ItemsPanel is made by a DockPanel.
Inside of the DockPanel, I can have one, two, or three buttons. The problem arises from the width of the buttons: I want the three elements with the same size, but the elements take the size that they need (the last element take the excess width because LastChildFill is true).
Can I give the buttons the same width without providing their size manually?
<ItemsControl ItemTemplate="{StaticResource Template1}" ItemsSource="{Binding Path=options, Mode=OneWay}" ItemsPanel="{StaticResource Panel1}" HorizontalContentAlignment="Stretch"/>
<ItemsPanelTemplate x:Key="Panel1">
<DockPanel Height="Auto" Width="Auto" LastChildFill="True"/>
</ItemsPanelTemplate>
<DataTemplate x:Key="BasicasTemplateOpciones" DataType="{x:Type local:MyOption}">
<Grid HorizontalAlignment="Stretch">
<Button DataContext="{Binding}" HorizontalContentAlignment="Stretch" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" >
<Button.Template>
<ControlTemplate TargetType="{x:Type Button}">
<Grid HorizontalAlignment="Stretch" VerticalAlignment="Center">
<StackPanel Orientation="Horizontal">
<TextBlock HorizontalAlignment="Center" VerticalAlignment="Stretch"/>
<TextBlock HorizontalAlignment="Right" VerticalAlignment="Stretch"/>
</StackPanel>
</Grid>
</ControlTemplate>
</Button.Template>
</Button>
</Grid>
</DataTemplate>

Answer 1

A UniformGrid with a single row will do what you want:
<ItemsPanelTemplate x:Key="Panel1">
<UniformGrid Rows="1" />
</ItemsPanelTemplate>
Example:
<StackPanel Orientation="Vertical">
<StackPanel.Resources>
<ItemsPanelTemplate x:Key="Panel1">
<UniformGrid Rows="1" />
</ItemsPanelTemplate>
<Style TargetType="ItemsControl" x:Key="ICStyle">
<Style.Resources>
<Style TargetType="Button">
<Setter Property="Margin" Value="2" />
</Style>
</Style.Resources>
<Setter Property="ItemsPanel" Value="{StaticResource Panel1}" />
</Style>
</StackPanel.Resources>
<ItemsControl Style="{StaticResource ICStyle}">
<Button>Foo</Button>
</ItemsControl>
<ItemsControl Style="{StaticResource ICStyle}">
<Button>Foo</Button>
<Button>Bar</Button>
</ItemsControl>
<ItemsControl Style="{StaticResource ICStyle}">
<Button>Foo</Button>
<Button>Bar</Button>
<Button>Baz</Button>
</ItemsControl>
</StackPanel>