超炫酷的WPF实现Loading控件效果

<p>Win8系统的Loading效果还是很不错的，网上也有人用CSS3等技术实现，研究了一下，并打算用WPF自定义一个Loading控件实现类似的效果，并可以让用户对Loading的颗粒（Particle）背景颜色进行自定义，话不多说，直接上代码：</p>
<p>1、用VS2012新建一个WPF的用户控件库项目WpfControlLibraryDemo，VS自动生成如下结构：</p>
<p style="text-align: center"><img alt="" id="theimg" onclick="window.open(this.src)" src="https://beijingoptbbs.oss-cn-hangzhou.aliyuncs.com/jb/2426819-cdc1833a0ef508bcc4484986c3897aec"></p>
<p>2、删除UserControl1.xaml，并新建一个Loading的CustomControl(不是UserControl),如下图所示：</p>
<p style="text-align: center"><img alt="" id="theimg" onclick="window.open(this.src)" src="https://beijingoptbbs.oss-cn-hangzhou.aliyuncs.com/jb/2426819-71745880d2a4776f4f261b10f473c2ea"></p>
<p>3、如果报错找不到Loading类型，请编译，下面在Generic.xaml主题文件中对Loading的样式和内容进行定义（注意添加</p>
<div class="blockcode">
<pre class="brush:csharp;">
xmlns:system = "clr-namespace:System;assembly=mscorlib"），代码如下：
<ResourceDictionary
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:system = "clr-namespace:System;assembly=mscorlib"
xmlns:local="clr-namespace:WpfControlLibraryDemo">

<Style TargetType="{x:Type local:Loading}">
<Setter Property="Template">
  <Setter.Value>
  <ControlTemplate TargetType="{x:Type local:Loading}">
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<Grid Width = "50" Height = "50">
<Grid.Resources>



<SolidColorBrush x:Key = "ParticleColor" Color = "{Binding Path=FillColor,RelativeSource={RelativeSource TemplatedParent}}" />
<SolidColorBrush x:Key = "ParticleBackgroundColor" Color = "Transparent"/>
<system:Double x:Key = "ParticleOpacity">1</system:Double>
<system:Double x:Key = "ParticleRadius">5</system:Double>

<system:Double x:Key = "StartingPointX">0</system:Double>
<system:Double x:Key = "StartingPointY">-20</system:Double>

<system:Double x:Key = "RotationPointX">0.5</system:Double>
<system:Double x:Key = "RotationPointY">0.5</system:Double>


<system:TimeSpan x:Key = "StoryBoardBeginTimeP0">00:00:00.000</system:TimeSpan>
<system:TimeSpan x:Key = "StoryBoardBeginTimeP1">00:00:00.100</system:TimeSpan>
<system:TimeSpan x:Key = "StoryBoardBeginTimeP2">00:00:00.200</system:TimeSpan>
<system:TimeSpan x:Key = "StoryBoardBeginTimeP3">00:00:00.300</system:TimeSpan>
<system:TimeSpan x:Key = "StoryBoardBeginTimeP4">00:00:00.400</system:TimeSpan>
<Duration x:Key = "StoryBoardDuration">00:00:01.800</Duration>


<system:Double x:Key = "ParticleOriginAngleP0">0</system:Double>
<system:Double x:Key = "ParticleOriginAngleP1">-10</system:Double>
<system:Double x:Key = "ParticleOriginAngleP2">-20</system:Double>
<system:Double x:Key = "ParticleOriginAngleP3">-30</system:Double>
<system:Double x:Key = "ParticleOriginAngleP4">-40</system:Double>


<system:Double x:Key = "ParticleBeginAngle1">0</system:Double>
<system:Double x:Key = "ParticleEndAngle1">90</system:Double>
<system:TimeSpan x:Key = "ParticleBeginTime1">00:00:00.000</system:TimeSpan>
<Duration x:Key = "ParticleDuration1">00:00:00.750</Duration>


<system:Double x:Key = "ParticleBeginAngle2">90</system:Double>
<system:Double x:Key = "ParticleEndAngle2">270</system:Double>
<system:TimeSpan x:Key = "ParticleBeginTime2">00:00:00.751</system:TimeSpan>
<Duration x:Key = "ParticleDuration2">00:00:00.300</Duration>


<system:Double x:Key = "ParticleBeginAngle3">270</system:Double>
<system:Double x:Key = "ParticleEndAngle3">360</system:Double>
<system:TimeSpan x:Key = "ParticleBeginTime3">00:00:01.052</system:TimeSpan>
<Duration x:Key = "ParticleDuration3">00:00:00.750</Duration>

<Style x:Key = "EllipseStyle" TargetType = "Ellipse">
   <Setter Property = "Width" Value = "{StaticResource ParticleRadius}"/>
   <Setter Property = "Height" Value = "{StaticResource ParticleRadius}"/>
   <Setter Property = "Fill" Value = "{StaticResource ParticleColor}"/>
   <Setter Property = "RenderTransformOrigin" Value = "0.5, 0.5"/>
   <Setter Property = "Opacity" Value = "{StaticResource ParticleOpacity}"/>
</Style>
</Grid.Resources>
<Canvas Width = "1" Height = "1" Margin="0,0,0,0">
<Canvas.Triggers>
   <EventTrigger RoutedEvent = "Canvas.Loaded">