Dragging custom window title bar from top when maximized does not work

I am able to get the desired behavior of title bar including aero snap in pure xaml

as result you can see a custom title bar, it is completely draggable, double click to maximize and restore and drag to snap and unsnap.

xaml

<Window x:Class="CSharpWPF.MainWindow"             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"            Title="MainWindow" >    <WindowChrome.WindowChrome>        <WindowChrome CaptionHeight="{Binding ActualHeight,ElementName=titlebar}"/>    </WindowChrome.WindowChrome>    <DockPanel LastChildFill="True">        <Border Background="LightBlue" DockPanel.Dock="Top" Height="25" x:Name="titlebar">            <TextBlock Text="{Binding Title, RelativeSource={RelativeSource FindAncestor,AncestorType=Window},FallbackValue=Title}"                        Margin="10,0,0,0"                       VerticalAlignment="Center">                <TextBlock.Effect>                    <DropShadowEffect Color="White" ShadowDepth="3"/>                </TextBlock.Effect>            </TextBlock>        </Border>        <Border BorderBrush="LightGray" BorderThickness="1" Padding="4">            <TextBlock Text="Window content"/>        </Border>    </DockPanel></Window>

result

so now you don't need any code behind to handle title bar manually.

Reusable styles

you can also wrap above in a custom style which you can apply on several windows

<Style TargetType="Window" x:Key="CustomTitleBar">    <Setter Property="WindowChrome.WindowChrome">        <Setter.Value>            <WindowChrome CaptionHeight="{x:Static SystemParameters.CaptionHeight}" />        </Setter.Value>    </Setter>    <Setter Property="Template">        <Setter.Value>            <ControlTemplate TargetType="Window">                <DockPanel LastChildFill="True">                    <Border Background="LightBlue" DockPanel.Dock="Top"                             Height="{x:Static SystemParameters.CaptionHeight}" x:Name="titlebar">                        <Grid>                            <TextBlock Text="{TemplateBinding Title}"                                         Margin="10,0,0,0"                                        VerticalAlignment="Center">                                <TextBlock.Effect>                                    <DropShadowEffect Color="White" ShadowDepth="3"/>                                </TextBlock.Effect>                            </TextBlock>                        </Grid>                    </Border>                    <Border Background="{TemplateBinding Background}" BorderBrush="LightGray"                             BorderThickness="1" Padding="4">                        <ContentPresenter/>                    </Border>                </DockPanel>            </ControlTemplate>        </Setter.Value>    </Setter></Style>

usage

<Window x:Class="CSharpWPF.View"                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"                xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"                Title="MainWindow"                 Style="{StaticResource CustomTitleBar}" >    <TextBlock Text="Window content"/></Window>

How to implement in your code

After looking at your code, I did manage to implement it with very little changes

Changes are

File: CustomChrome.cs

line 41: change CaptionHeight = 36, currently it is 0. this should be equal to your title bar height

var chrome = new WindowChrome() { GlassFrameThickness = new Thickness(-1), CaptionHeight = 36 };

line 60: remove ((FrameworkElement)sender).MouseDown += TitleBar_MouseDown; as not required

line 70: remove no more used event TitleBar_MouseDown

File: CornerButtons.xaml

line 13: add WindowChrome.IsHitTestVisibleInChrome="True" to StackPanel

    <StackPanel SnapsToDevicePixels="True" Orientation="Horizontal" WindowChrome.IsHitTestVisibleInChrome="True">

File: MainWindow.xaml

line 17: add WindowChrome.IsHitTestVisibleInChrome="True" to StackPanel

<cc:CornerButtons Grid.Column="2">    <StackPanel Orientation="Horizontal"                WindowChrome.IsHitTestVisibleInChrome="True">

this is all, and your app will have a normal title bar without need to handle custom logic