Question

我在ResourceDirectory中定义了一个样式代码来为弹出窗口设置动画。这是WPF代码：

<Style x:Key="Hardwarepopups" TargetType="Popup">
    <Style.Triggers>
        <Trigger Property="IsOpen" Value="True">
            <Trigger.EnterActions>
                <BeginStoryboard >
                    <Storyboard>
                        <DoubleAnimation Duration="0:0:.3" Storyboard.TargetProperty="Width" From="0" To="100" AccelerationRatio=".1"/>
                    </Storyboard>
                </BeginStoryboard>
            </Trigger.EnterActions>
        </Trigger>
    </Style.Triggers>
</Style>

这是弹出窗口：

<Popup Height="Auto" Width="Auto" Name="HardwareToolTip" StaysOpen="True" AllowsTransparency="True" Style="{StaticResource Hardwarepopups}">

通过处理XAML中的所有内容，效果很好。我决定将其转换为C＃代码，如下所示：

void SetHarwareStyle(Popup B) {
    var RightToLeft = new DoubleAnimation()
    {
    From = 0,
    To = 100,
    Duration = TimeSpan.FromMilliseconds(300),
    AccelerationRatio = 0.1
    };
    Storyboard.SetTargetProperty(RightToLeft, new PropertyPath(WidthProperty));
    Storyboard C = new Storyboard();
    C.Children.Add(RightToLeft);

    var action = new BeginStoryboard();
    action.Storyboard = C;

    Trigger A = new Trigger { Property = Popup.IsOpenProperty, Value = true };
    A.EnterActions.Add(action);

    B.Triggers.Add(A);
}

但是这一行B.Triggers.Add(A);给出了错误System.InvalidOperationException: 'Triggers collection members must be of type EventTrigger.' 我怎么解决这个问题？这种转换的建议是在运行时更改To的{{1}}属性。

Answer 1

问题中的代码不能完全反映XAML：缺少样式。

我重命名了一些变量以使其更易于阅读（并防止出现此类错误）

顺便说一句：rightToLeftAnimation应该命名为leftToRightAnimation。

void SetHarwareStyle(Popup popup)
{
    var rightToLeftAnimation = new DoubleAnimation()
    {
        From = 0,
        To = 100,
        Duration = TimeSpan.FromMilliseconds(300),
        AccelerationRatio = 0.1
    };
    Storyboard.SetTargetProperty(rightToLeftAnimation, new PropertyPath(WidthProperty));
    var storyboard = new Storyboard();
    storyboard.Children.Add(rightToLeftAnimation);

    var beginStoryboard = new BeginStoryboard();
    beginStoryboard.Storyboard = storyboard;

    var trigger = new Trigger { Property = Popup.IsOpenProperty, Value = true };
    trigger.EnterActions.Add(beginStoryboard);

    var style= new Style();
    style.TargetType = typeof(Popup);
    style.Triggers.Add(trigger);

    popup.Style = style;
}

C＃.net-将动画样式转换为背后的代码

1 个答案: