Is not necessary to alter all the forms, just change the style of the default DataGrid. For this purpose, has been prepared dictionary ItemsFilterStyle.xaml. After inclusion in the resource ItemsFilterStyle.xaml all DataGrid in the project will gain quick filter in the header.
How use.

App.xaml
<Application x:Class="Northwind.NET.Sample.App"
            xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="Themes/ItemsFilterStyle.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

How work.

ItemsFilterStyle.xaml
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                   xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                   xmlns:bsFilter="http://schemas.bolapansoft.com/xaml/Controls/ItemsFilter"
                   >
...
    <Style x:Key="DataGridColumnHeaderStyle" TargetType="{x:Type DataGridColumnHeader}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type DataGridColumnHeader}">
                        <Grid >
                            ...
                            <bsFilter:ColumnFilter
                               ParentCollection="{Binding ItemsSource,
                                   RelativeSource={RelativeSource FindAncestor,
                                   AncestorType={x:Type DataGrid}}}" />
                        </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style TargetType="{x:Type DataGrid}">
        <Setter Property="ColumnHeaderStyle" Value="{StaticResource DataGridColumnHeaderStyle}" />
    </Style>
</ResourceDictionary>

The file ItemsFilterStyle.xaml given the appearance of all the controls in ItemsFilter, so you will be able to customize the style according to individual design of your application.

Last edited Nov 9, 2013 at 4:16 AM by Mishkin, version 4