Question

Using .NET 3.5

I have a UserControl with a LinearGradientBrush for the background.

I’m wondering how can I cause the whole control to change to a different color and pulsate when a property on the user control changes.

For example if I say MyUserControl.Prop1 = 20 then change the color to red and pulse (by pulsating I mean geting brighter then darker and toggling back and forth). Then when MyUserControl.Prop1 = 0 it returns back the original color.

I would preferably like to keep the gradient background when pusating a different color but if this isn’t possible then so be it

Any pointers or links would be great. I’ve googled this but didn’t find anything useful.

This is my UserControl

<UserControl x:Class="StatusPanel"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Margin="11" >

<Grid>
    <Border Margin="-5" BorderBrush="Black" BorderThickness="1" CornerRadius="30" >
    <Border.Effect>
        <DropShadowEffect />
    </Border.Effect>

    <Border.Background >
        <LinearGradientBrush EndPoint="0,0" StartPoint="1,1">
            <GradientStop Color="White" Offset="0"/>
            <GradientStop Color="Silver" Offset="1"/>
        </LinearGradientBrush>
    </Border.Background>
    </Border>

    <StackPanel Orientation="Vertical">
            <!-- All my user contraols defined here -->
    </StackPanel>    
</Grid>    
</UserControl>

Answer 1

Can’t post comments for some reason!

Good answer Greg, thanks for that. Unfortunatly i’m using 3.5 .. forgot to mention that when I first asked the Q

this is what I did to solve it:

<UserControl.Resources>
    <Storyboard Name="FadeOutStoryboard" x:Key="FadeOutStoryboard" >
        <DoubleAnimation Storyboard.TargetName="userControlStatusPanel" 
                         Storyboard.TargetProperty="Opacity" 
                         From="1" To="0" Duration="0:0:3" RepeatBehavior="Forever"  />
    </Storyboard>
</UserControl.Resources>

        Storyboard sb = (Storyboard)UserControl.FindResource("FadeOutStoryboard");
        LinearGradientBrush myBrush = new LinearGradientBrush();
        myBrush.EndPoint = new Point(0, 0);
        myBrush.StartPoint = new Point(1, 1);

        if (runProgress.Percent == 100)
        {
            myBrush.GradientStops.Add(new GradientStop(Colors.Green, 0));
            myBrush.GradientStops.Add(new GradientStop(Colors.Silver, 1));
            sb.Stop();
        }
        else (runProgress.Percent <= 100)
        {
            myBrush.GradientStops.Add(new GradientStop(Colors.Red, 0));
            myBrush.GradientStops.Add(new GradientStop(Colors.Silver, 1));
            sb.Begin();
        }
        UserControl.borderMain.Background = myBrush;
    }