如何在AdaptiveTrigger UWP中设置绑定到页面元素ActualWidth的ScrollViewer宽度

<ScrollViewer x:Name="myScrollViewer" HorizontalScrollBarVisibility="Auto">
    <!-- 内容 -->
</ScrollViewer>

<VisualStateManager.VisualStateGroups>
    <VisualStateGroup>
        <VisualState>
            <VisualState.StateTriggers>
                <AdaptiveTrigger MinWindowWidth="0" />
            </VisualState.StateTriggers>
            <VisualState.Setters>
                <!-- 设置ScrollViewer的宽度 -->
                <Setter Target="myScrollViewer.Width" Value="{Binding ElementName=myScrollViewer, Path=ActualWidth}" />
            </VisualState.Setters>
        </VisualState>
    </VisualStateGroup>
</VisualStateManager.VisualStateGroups>

private void Page_Loaded(object sender, RoutedEventArgs e)
{
    VisualStateManager.GoToState(this, "DefaultState", false);
}