允许内部水平滚动ScrollViewer内部的外部ScrollViewer垂直滚动

Question

当您在ScrollViewer中拥有ScrollViewer时，使用滚轮滚动仅限于内部滚动。 当它们具有相同的“方向”时，这是有道理的。 但是当外部只允许垂直滚动，而内部只允许水平滚动时，我希望内部鼠标内部的鼠标滚轮滚动可以在外部ScrollViewer中垂直滚动。 没有。 有没有办法做到这一点？

在以下代码中，尝试在红色字母区域内使用滚轮：

<ScrollViewer VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Disabled">
    <StackPanel>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>
        <TextBlock>aaaaaaaaaaaaaaaaaa</TextBlock>

        <ScrollViewer VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Auto">
            <StackPanel >
                <TextBlock Foreground="Red">aaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbb cccccccccccccccccccccc dddddddddddddddddddddd eeeeeeeeeeeeeeeeeeeee fffffffffffffffff ggggggggggggggggggggggg</TextBlock>
                <TextBlock Foreground="Red">aaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbb cccccccccccccccccccccc dddddddddddddddddddddd eeeeeeeeeeeeeeeeeeeee fffffffffffffffff ggggggggggggggggggggggg</TextBlock>
                <TextBlock Foreground="Red">aaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbb cccccccccccccccccccccc dddddddddddddddddddddd eeeeeeeeeeeeeeeeeeeee fffffffffffffffff ggggggggggggggggggggggg</TextBlock>
                <TextBlock Foreground="Red">aaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbb cccccccccccccccccccccc dddddddddddddddddddddd eeeeeeeeeeeeeeeeeeeee fffffffffffffffff ggggggggggggggggggggggg</TextBlock>
            </StackPanel>
        </ScrollViewer>
    </StackPanel>
</ScrollViewer>

Answer 1

如果可以使用后台代码，则可以为“子级” ScollViewer的PreviewMouseWheel事件创建一个事件处理程序，并且在该事件处理程序中，可以将MouseWheelEventArgs信息传递给“父级” ScrollViewer以引发自己的MouseWheel事件。

首先，将对XAML进行一些小的更改：

给“父级” ScrollViewer命名，以便可以从后面的代码中引用它：

<ScrollViewer x:Name="parentScrollViewer"
              VerticalScrollBarVisibility="Auto"
              HorizontalScrollBarVisibility="Disabled">

为“子级” ScrollViewer的PreviewMouseWheel事件创建事件处理程序：

<ScrollViewer VerticalScrollBarVisibility="Disabled"
              HorizontalScrollBarVisibility="Auto" 
              PreviewMouseWheel="ScrollViewer_PreviewMouseWheel">

最后，在事件处理程序中实现代码以引发“父” MouseWheel事件：

private void ScrollViewer_PreviewMouseWheel(object sender, MouseWheelEventArgs e)
{
    var mouseWheelEventArgs = new MouseWheelEventArgs(e.MouseDevice, e.Timestamp, e.Delta);
    mouseWheelEventArgs.RoutedEvent = ScrollViewer.MouseWheelEvent;
    mouseWheelEventArgs.Source = sender;
    this.parentScrollViewer.RaiseEvent(mouseWheelEventArgs);
}