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How to make an ellipse blink?

I am trying to create a custom control in WPF. I want it to mimic the behavior of an LED that may flash.

Controls have three states: On, Off. and blinking.

I know how to set On and Off through the code behind, but this WPF animation stuff is just driving me crazy! I can’t revive anything. The plan is to have a property called the state. When the user sets the value to blink, I want the control to alternate between green and gray. I assume that I need the dependency property here, but I have no idea. I used to have more xaml, but I just erased it. he does not do anything. I would like to do this in best practice, but for now I will take anything. I am halfway to writing a thread that changes color manually at this point.

<UserControl x:Class="WpfAnimation.LED"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Height="300" Width="300">

<Grid>
    <Ellipse x:Name="MyLight" Height="Auto" Width="Auto"/>
</Grid>

</UserControl>
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2 answers

, ( Silverlight):

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="Blinker.MainPage"
    Width="640" Height="480" Loaded="UserControl_Loaded">
    <UserControl.Resources>
        <Storyboard x:Name="Blink" AutoReverse="True" RepeatBehavior="Forever">
            <ColorAnimationUsingKeyFrames BeginTime="00:00:00"
              Storyboard.TargetName="ellipse"
              Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)">
                 <EasingColorKeyFrame KeyTime="00:00:01" Value="Gray"/>
            </ColorAnimationUsingKeyFrames>
         </Storyboard>
    </UserControl.Resources>
    <Grid x:Name="LayoutRoot" Background="White">
         <Ellipse x:Name="ellipse" Fill="Green" Stroke="Black"/>
    </Grid>
</UserControl>

, - ,

private bool blinking;
public bool IsBlinking
{
    get
    {
       return blinking;
    }
    set
    {
        if (value)
        {
             this.Blink.Begin();
        }
        else
        {
             this.Blink.Stop();
        }

        this.blinking = value;
    }
}

:

private void UserControl_Loaded(object sender, System.Windows.RoutedEventArgs e)
{
    this.Blink.Begin();
}

WPF - VisualStateManager - Silverlight:

<UserControl
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Class="BlinkerApp.Blinker"
x:Name="UserControl"
d:DesignWidth="100" d:DesignHeight="100">
<Grid x:Name="LayoutRoot">
    <VisualStateManager.VisualStateGroups>
        <VisualStateGroup x:Name="BlinkStates">
            <VisualState x:Name="Blinking">
                <Storyboard AutoReverse="True" RepeatBehavior="Forever">
                    <ColorAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="ellipse" Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)">
                        <SplineColorKeyFrame KeyTime="00:00:01" Value="Gray"/>
                    </ColorAnimationUsingKeyFrames>
                </Storyboard>
            </VisualState>
            <VisualState x:Name="Stopped"/>
        </VisualStateGroup>
    </VisualStateManager.VisualStateGroups>
    <Ellipse x:Name="ellipse" Fill="Green" Stroke="Black"/>
</Grid>

IsBlinking :

namespace BlinkerApp
{
    using System.Windows;
    using System.Windows.Controls;

/// <summary>
/// Interaction logic for Blinker.xaml
/// </summary>
public partial class Blinker : UserControl
{
    private bool blinking;

    public Blinker()
    {
        this.InitializeComponent();
    }

    public bool IsBlinking
    {    
        get    
        {       
            return blinking;    
        }    

        set    
        {        
            if (value)        
            {
                VisualStateManager.GoToState(this, "Blinking", true);
            }        
            else        
            {
                VisualStateManager.GoToState(this, "Stopped", true);
            }        

            this.blinking = value;    
        }
    }       
}
}
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​​ , UserControl Blink:

public static readonly RoutedEvent BlinkEvent = EventManager.RegisterRoutedEvent("Blink", RoutingStrategy.Direct, typeof(RoutedEventHandler), typeof(LedControl));
public event RoutedEventHandler Blink
{
    add { AddHandler(BlinkEvent, value); }
    remove { RemoveHandler(BlinkEvent, value); }
}

, , ( , :

RaiseEvent(new RoutedEventArgs(LedControl.Blink));

XAML (ledEllipse) - , "" ( , ). , .

<UserControl.Triggers>
    <EventTrigger RoutedEvent="local:LedControl.Blink">
        <EventTrigger.Actions>
            <BeginStoryboard>
                <Storyboard>
                    <DoubleAnimation Storyboard.TargetName="glow"
                                     Storyboard.TargetProperty="Opacity"
                                     To="100"
                                     AutoReverse="True"
                                     Duration="0:0:0.075" />
                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ledEllipse"
                                                  Storyboard.TargetProperty="Fill"
                                                  Duration="0:0:0.15">
                        <ObjectAnimationUsingKeyFrames.KeyFrames>
                            <DiscreteObjectKeyFrame KeyTime="0:0:0.01">
                                <DiscreteObjectKeyFrame.Value>
                                    <RadialGradientBrush>
                                        <!--bright Green Brush-->
                                        <GradientStop Color="#FF215416" Offset="1"/>
                                        <GradientStop Color="#FE38DA2E" Offset="0"/>
                                        <GradientStop Color="#FE81FF79" Offset="0.688"/>
                                    </RadialGradientBrush>
                                </DiscreteObjectKeyFrame.Value>
                            </DiscreteObjectKeyFrame>
                            <DiscreteObjectKeyFrame KeyTime="0:0:0.15" >
                                <DiscreteObjectKeyFrame.Value>
                                    <RadialGradientBrush>
                                        <!--dim Green Brush-->
                                        <GradientStop Color="#FF21471A" Offset="1"/>
                                        <GradientStop Color="#FF33802F" Offset="0"/>
                                        <GradientStop Color="#FF35932F" Offset="0.688"/>
                                    </RadialGradientBrush>
                                </DiscreteObjectKeyFrame.Value>
                            </DiscreteObjectKeyFrame>
                        </ObjectAnimationUsingKeyFrames.KeyFrames>
                    </ObjectAnimationUsingKeyFrames>
                </Storyboard>
            </BeginStoryboard>
        </EventTrigger.Actions>
    </EventTrigger>
</UserControl.Triggers>

, "ledEllipse", "" DropShadowEffect, ledControl (redLight - , ):

<Ellipse x:Name="statusLight" Height="16" Width="16" Margin="0" Fill="{DynamicResource redLight}" >
    <Ellipse.Effect>
        <DropShadowEffect x:Name="glow" ShadowDepth="0" Color="Lime" BlurRadius="10" Opacity="0" />
    </Ellipse.Effect>
</Ellipse>

. DropShadowEffect .Net 3.5, , ( ).

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