一、下载dll:http://wpftoolkit.codeplex.com/releases/view/99072
下载之后将WPFToolkit引用到WPF项目下;
二、添加命名空间:
xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"
三、使用/设置(三种效果):

1.
<xctk:BusyIndicator IsBusy="True" >
<ContentControl Style="{StaticResource SampleContent}"/>
</xctk:BusyIndicator>
2.
<xctk:BusyIndicator IsBusy="True" BusyContent="Downloading email..." >
<ContentControl Style="{StaticResource SampleContent}"/>
</xctk:BusyIndicator>
3.
<xctk:BusyIndicator IsBusy="True" DisplayAfter="0">
<xctk:BusyIndicator.BusyContentTemplate>
<DataTemplate>
<StackPanel Margin="4">
<TextBlock Text="Downloading Email" FontWeight="Bold" HorizontalAlignment="Center"/>
<StackPanel Margin="4">
<TextBlock Text="Downloading message 4/10..."/>
<ProgressBar Value="40" Height="15"/>
</StackPanel>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Button Grid.Column="0" Content="Pause" HorizontalAlignment="Right" Margin="0 0 2 0"/>
<Button Grid.Column="1" Content="Cancel" HorizontalAlignment="Left" Margin="2 0 0 0"/>
</Grid>
</StackPanel>
</DataTemplate>
</xctk:BusyIndicator.BusyContentTemplate>
<xctk:BusyIndicator.OverlayStyle>
<Style TargetType="Rectangle">
<Setter Property="Fill" Value="#ffffeeee"/>
</Style>
</xctk:BusyIndicator.OverlayStyle>
<xctk:BusyIndicator.ProgressBarStyle>
<Style TargetType="ProgressBar">
<Setter Property="Visibility" Value="Collapsed"/>
</Style>
</xctk:BusyIndicator.ProgressBarStyle>
<ContentControl Style="{StaticResource SampleContent}"/>
</xctk:BusyIndicator>
参考引用:http://wpftoolkit.codeplex.com/wikipage?title=BusyIndicator&referringTitle=Home