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如何停止動畫,以免產生Completed
事件。下面是簡單的例子如何停止動畫WPF?
<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>
和備份代碼:
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;
}
如果我將鼠標移動之前的矩形變爲白色它仍然會在一段時間後顯示彈出式窗口。如何防止這一點?我們假設Border_MouseLeave
和Border_MouseEnter
方法互不知道(它們不能將動畫實例變量傳遞給對方)。