如何动画渐变式颜色

Question

我在下面尝试了代码，但是在行中有问题" storyboard.settargetProperty(CA1，new Propertypath(" gradientstop.colorproperty"((;

(;

sb.begin(this(投掷了无效的exception，无法解决" gradstop1.colorproperty"。

如何正确地动画渐变式颜色？

private void UserControl_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        LinearGradientBrush lgb = new LinearGradientBrush(
           (Color)ColorConverter.ConvertFromString("#FF1E2838"),
           (Color)ColorConverter.ConvertFromString("#FF2B364F"),
           new Point(0.5, 0),
           new Point(0.5, 1));
        UCBody.Background = lgb;
        ColorAnimation ca1 = new ColorAnimation(
            (Color)ColorConverter.ConvertFromString("#FF1E2838"),
            (Color)ColorConverter.ConvertFromString("#FF1E1E1E"),
            TimeSpan.FromMilliseconds(600));
        ColorAnimation ca2 = new ColorAnimation(
            (Color)ColorConverter.ConvertFromString("#FF2B364F"),
            (Color)ColorConverter.ConvertFromString("#FF2B2B38"),
            TimeSpan.FromMilliseconds(600));
        Storyboard sb = new Storyboard();
        sb.Children.Add(ca1);
        sb.Children.Add(ca2);
        Storyboard.SetTargetName(ca1, "gradStop1");
        Storyboard.SetTargetProperty(ca1, new PropertyPath("GradientStop.ColorProperty"));
        Storyboard.SetTargetName(ca2, "gradStop2");
        Storyboard.SetTargetProperty(ca2, new PropertyPath("GradientStop.ColorProperty"));
        sb.Begin(this);
    }
}

Answer 1

您没有名为" gradstop1"或" gradstop2"的对象，但是您可以使用BeginAnimation方法来对LinearGradientBrush的梯度停止进行动画：

private void UserControl_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    LinearGradientBrush lgb = new LinearGradientBrush(
       (Color)ColorConverter.ConvertFromString("#FF1E2838"),
       (Color)ColorConverter.ConvertFromString("#FF2B364F"),
       new Point(0.5, 0),
       new Point(0.5, 1));
    UCBody.Background = lgb;
    ColorAnimation ca1 = new ColorAnimation(
        (Color)ColorConverter.ConvertFromString("#FF1E2838"),
        (Color)ColorConverter.ConvertFromString("#FF1E1E1E"),
        TimeSpan.FromMilliseconds(600));
    ColorAnimation ca2 = new ColorAnimation(
        (Color)ColorConverter.ConvertFromString("#FF2B364F"),
        (Color)ColorConverter.ConvertFromString("#FF2B2B38"),
        TimeSpan.FromMilliseconds(600));
    lgb.GradientStops[0].BeginAnimation(GradientStop.ColorProperty, ca1);
    lgb.GradientStops[1].BeginAnimation(GradientStop.ColorProperty, ca2);
}