Commands in MVVM

<UserControl x:Class="ControlsSample.Samples.CrossButton"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:apexControls="clr-namespace:Apex.Controls;assembly=Apex"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">
    <Grid>
        <apexControls:PaddedGrid 
            Padding="6"
            Rows="Auto,Auto,Auto,Auto" Columns="5*,*">
            
            <TextBlock Grid.Row="0" Grid.Column="0" TextWrapping="Wrap" 
                       Text="The cross button is a small and simple button with a cross, useful in certain circumstances." />
            <apexControls:CrossButton Grid.Row="0" Grid.Column="1" Width="12" Height="12" />

            <TextBlock Grid.Row="1" Grid.Column="0" TextWrapping="Wrap" 
                       Text="Paths are used rather than bitmaps so it can be scaled to any size." />
            <apexControls:CrossButton Grid.Row="1" Grid.Column="1" Width="20" Height="20" />
            
        </apexControls:PaddedGrid>

    </Grid>
</UserControl>