如何停止动画WPF?

时间:2012-02-07 12:20:08

标签: c# .net wpf xaml animation

如何停止动画以使其不会产生Completed事件。这是一个简单的例子

<Window x:Class="WpfApplication5.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="248" Width="318">
    <Grid>
        <Border Width="20" Height="20" Background="Red" MouseEnter="Border_MouseEnter" MouseLeave="Border_MouseLeave" x:Name="border" />
    </Grid>
</Window>

支持代码:

private void Border_MouseEnter(object sender, MouseEventArgs e)
{
    var a = new DoubleAnimation { To = 0, Duration = TimeSpan.FromMilliseconds(4000) };
    a.Completed += (obj, args) => MessageBox.Show("Boom!");
    border.BeginAnimation(Border.OpacityProperty, a);
}

private void Border_MouseLeave(object sender, MouseEventArgs e)
{
    border.BeginAnimation(Border.OpacityProperty, null);
    border.Opacity = 1;
}

如果我在矩形变为白色之前移出鼠标,它会在一段时间后显示弹出窗口。怎么预防这个?我们假设Border_MouseLeaveBorder_MouseEnter方法彼此不了解(它们不能相互传递动画实例变量)。

2 个答案:

答案 0 :(得分:6)

你可以用这个:

<Border Width="20" Height="20" Background="Red" x:Name="border" >
                <Border.Triggers>
                    <EventTrigger RoutedEvent="MouseEnter">
                        <BeginStoryboard Name="Ali">
                            <Storyboard>
                                <DoubleAnimation To="0" Duration="0:0:4" Completed="com" Storyboard.TargetProperty="Opacity"/>
                            </Storyboard>
                        </BeginStoryboard>
                    </EventTrigger>
                    <EventTrigger RoutedEvent="MouseLeave">
                        <StopStoryboard  BeginStoryboardName="Ali"/>
                    </EventTrigger>
                </Border.Triggers>
            </Border>

和:

private void com(object sender, EventArgs e)
        {
            MessageBox.Show("boom!");
        }

答案 1 :(得分:1)

您可以使用Property或Data Trigger的EnterActions和ExitActions属性,或者@Ali表示正确使用Begin and Stop故事板。