我找不到像 IsScrolling 这样的东西,所以我会这样处理它:
<Popup Name="docPopup" AllowsTransparency="True" PlacementTarget="{x:Reference docViewer}" Placement="Center">
<Border Background="Black" CornerRadius="5" Padding="10" BorderBrush="White" BorderThickness="1">
<TextBlock Foreground="White">
<Run Text="{Binding ElementName=docViewer, Path=MasterPageNumber, Mode=OneWay}"/>
<Run Text=" / "/>
<Run Text="{Binding ElementName=docViewer, Path=PageCount, Mode=OneWay}"/>
</TextBlock>
</Border>
</Popup>
<DocumentViewer Name="docViewer" ScrollViewer.ScrollChanged="docViewer_ScrollChanged"/>
当文档滚动时应该显示弹出窗口,然后它应该在一段时间后淡出。这是在处理程序中完成的:
DoubleAnimationUsingKeyFrames anim;
private void docViewer_ScrollChanged(object sender, ScrollChangedEventArgs e)
{
if (anim == null)
{
anim = new DoubleAnimationUsingKeyFrames();
anim.Duration = (Duration)TimeSpan.FromSeconds(1);
anim.KeyFrames.Add(new DiscreteDoubleKeyFrame(1, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0))));
anim.KeyFrames.Add(new DiscreteDoubleKeyFrame(1, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0.5))));
anim.KeyFrames.Add(new LinearDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1))));
}
anim.Completed -= anim_Completed;
docPopup.Child.BeginAnimation(UIElement.OpacityProperty, null);
docPopup.Child.Opacity = 1;
docPopup.IsOpen = true;
anim.Completed += anim_Completed;
docPopup.Child.BeginAnimation(UIElement.OpacityProperty, anim);
}
void anim_Completed(object sender, EventArgs e)
{
docPopup.IsOpen = false;
}
编辑:该事件也会在通过鼠标滚轮等完成的滚动时触发。您可以将处理程序中的所有内容包装在 if (Mouse.LeftButton == MouseButtonState.Pressed) 中,不是 100% 准确,而是在左侧使用 MouseWheel 滚动 -点击?