Black background of WPF Window

I created simple window and applied style to it. Now, when I run application background is black:

In XAML it looks normal:

What is causing this?

Here is XAML code:

<Window SizeToContent="WidthAndHeight" 
                  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
                  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                  x:Class="WPFTest.MainWindow">
    <Window.Style>
        <Style TargetType="Window">
            <Setter Property="Control.Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Window">
                        <Grid Name="LayoutRoot" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
                            <Grid.RowDefinitions>
                                <RowDefinition Height="*" />
                                <RowDefinition Height="Auto" />
                            </Grid.RowDefinitions>

                            <Grid Grid.Row="0">
                                <ContentPresenter />
                            </Grid>
                            <StatusBar Name="statusBar1" Height="23" HorizontalAlignment="Stretch" VerticalAlignment="Top" Grid.Row="1" />
                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </Window.Style>
    <Grid>
        <Grid Height="114" HorizontalAlignment="Center" Margin="1,0,557,622" Name="grid" VerticalAlignment="Bottom" Width="466">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto" />
                <ColumnDefinition Width="100*" />
            </Grid.ColumnDefinitions>
            <Grid.RowDefinitions>
                <RowDefinition Height="25*" />
                <RowDefinition Height="25*" />
                <RowDefinition Height="25*" />
                <RowDefinition Height="25*" />
            </Grid.RowDefinitions>
            <Label Content="Label4" Grid.Column="0" Grid.Row="3" HorizontalAlignment="Left" Margin="3,0,3,0" MinHeight="16" MinWidth="97" Name="xResourceLabel4" VerticalAlignment="Bottom" />
            <Label Content="Label1" Grid.Column="0" Grid.Row="0" HorizontalAlignment="Left" Margin="3,0,3,0" MinHeight="16" MinWidth="98" Name="xResourceLabel1" VerticalAlignment="Bottom" />
            <Label Content="Label2" Grid.Column="0" Grid.Row="1" HorizontalAlignment="Left" Margin="3,0,3,0" MinHeight="16" MinWidth="114" Name="xResourceLabel2" VerticalAlignment="Bottom" />
            <Label Content="Label3" Grid.Column="0" Grid.Row="2" HorizontalAlignment="Left" Margin="3,0,3,0" MinHeight="16" MinWidth="80" Name="xResourceLabel3" VerticalAlignment="Bottom" />
            <TextBox Background="#FFFFFF99" Grid.ColumnSpan="2" HorizontalAlignment="Center" Margin="120,0,189,0" MinHeight="23" MinWidth="157" Name="tbREGNR" VerticalAlignment="Bottom" />
            <TextBox Background="#FFFFFF99" Grid.Column="1" Grid.Row="1" HorizontalAlignment="Center" Margin="0,0,189,0" MinHeight="23" MinWidth="157" Name="tbFaFabnr" VerticalAlignment="Bottom" />
            <ComboBox Background="#FFFFFF99" DisplayMemberPath="" Grid.Column="1" Grid.Row="2" HorizontalAlignment="Center" Margin="0,0,189,0" MinHeight="24" MinWidth="157" Name="cb" SelectedValuePath="" VerticalAlignment="Bottom" />
            <TextBox Background="#FFFF99CC" Grid.C开发者_StackOverflow中文版olumn="1" Grid.Row="3" HorizontalAlignment="Center" Margin="0,0,175,0" MinHeight="23" MinWidth="171" Name="tbComp" VerticalAlignment="Bottom" />
        </Grid>
    </Grid>
</Window>

---

<Grid Name="LayoutRoot" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="White">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="*" />
                            <RowDefinition Height="Auto" />
                        </Grid.RowDefinitions>
                        <Grid Grid.Row="0">
                            <ContentPresenter />
                        </Grid>
                        <StatusBar Name="statusBar1" Height="23" HorizontalAlignment="Stretch"    VerticalAlignment="Top" Grid.Row="1" />
                        </Grid>

Because you are overriding the default template for the Window you are taking away the style effects (of which one is background = black on the root grid)

see above, i've put it in the template and it should now work (Background="White")

Below is the default template for a window (Taken From Blend)

<ControlTemplate x:Key="WindowTemplateKey" TargetType="{x:Type Window}">
        <Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}">
            <Grid>
                <AdornerDecorator>
                    <ContentPresenter/>
                </AdornerDecorator>
                <ResizeGrip x:Name="WindowResizeGrip" HorizontalAlignment="Right" IsTabStop="false" Visibility="Collapsed" VerticalAlignment="Bottom"/>
            </Grid>
        </Border>
        <ControlTemplate.Triggers>
            <MultiTrigger>
                <MultiTrigger.Conditions>
                    <Condition Property="ResizeMode" Value="CanResizeWithGrip"/>
                    <Condition Property="WindowState" Value="Normal"/>
                </MultiTrigger.Conditions>
                <Setter Property="Visibility" TargetName="WindowResizeGrip" Value="Visible"/>
            </MultiTrigger>
        </ControlTemplate.Triggers>
    </ControlTemplate>
    <Style x:Key="WindowStyle1" TargetType="{x:Type Window}">
        <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
        <Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Window}">
                    <Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}">
                        <AdornerDecorator>
                            <ContentPresenter/>
                        </AdornerDecorator>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
        <Style.Triggers>
            <Trigger Property="ResizeMode" Value="CanResizeWithGrip">
                <Setter Property="Template" Value="{StaticResource WindowTemplateKey}"/>
            </Trigger>
        </Style.Triggers>
    </Style>

---

Based on TBohnen.jnr's answer, the actual correct answer would be do it as the default window template and add Background="{TemplateBinding Background}" to the top-level child element of the ControlTemplate. In the default template it is a Border, whereas in your case it's the Grid:

<Grid Background="{TemplateBinding Background}" Name="LayoutRoot" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">