WPF 等待加载效果

<UserControl x:Class="CustomControl.LoadingWait"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:CustomControl"
             mc:Ignorable="d" 
             IsVisibleChanged="HandleVisibleChanged">
    <UserControl.Background>
        <SolidColorBrush Color="Transparent"/>
    </UserControl.Background>
    <UserControl.Resources>
        <SolidColorBrush Color="#329FEE" x:Key="CirclesColor" />
        <!--<SolidColorBrush Color="Black" x:Key="BackgroundColor" Opacity=".20" />-->
    </UserControl.Resources>
    <Viewbox Width="50" Height="50"  
            HorizontalAlignment="Center"  
            VerticalAlignment="Center">
        <Grid x:Name="LayoutRoot"   
                Background="Transparent"  
                ToolTip="Please wait...."  
                HorizontalAlignment="Center"  
                VerticalAlignment="Center">
            <TextBlock Text="Loading..."  HorizontalAlignment="Center" VerticalAlignment="Center" FontSize="14" Foreground="#FFE3953D" FontWeight="Bold" />
            <Canvas RenderTransformOrigin="0.5,0.5"  
                    HorizontalAlignment="Center"  
                    VerticalAlignment="Center" Width="120"  
                    Height="120" Loaded="HandleLoaded"  
                    Unloaded="HandleUnloaded"  >
                <Ellipse x:Name="C0" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="1.0"/>
                <Ellipse x:Name="C1" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.9"/>
                <Ellipse x:Name="C2" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.8"/>
                <Ellipse x:Name="C3" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.7"/>
                <Ellipse x:Name="C4" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.6"/>
                <Ellipse x:Name="C5" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.5"/>
                <Ellipse x:Name="C6" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.4"/>
                <Ellipse x:Name="C7" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.3"/>
                <Ellipse x:Name="C8" Width="20" Height="20"  
                         Canvas.Left="0"  
                         Canvas.Top="0" Stretch="Fill"  
                         Fill="{StaticResource CirclesColor}" Opacity="0.2"/>
                <Canvas.RenderTransform>
                    <RotateTransform x:Name="SpinnerRotate"  
                         Angle="0" />
                </Canvas.RenderTransform>
            </Canvas>
        </Grid>
    </Viewbox>
</UserControl>

使用：

<local:LoadingWait x:Name="_loading"  Visibility="Collapsed" Grid.Row="1" HorizontalAlignment="Center" Margin="0,-120,0,0"/>

控制隐藏或显示

this._loading.Visibility = Visibility.Visible;

this._loading.Visibility = Visibility.Collapsed;