是否可以更改WPF ScrollViewer滚动的量?我只是想知道是否可以更改ScrollViewer,以便在使用鼠标滚轮或scrollviewer箭头时,可以更改增量滚动的数量。
是否可以更改WPF ScrollViewer滚动的量?我只是想知道是否可以更改ScrollViewer,以便在使用鼠标滚轮或scrollviewer箭头时,可以更改增量滚动的数量。
public class WheelSpeedScrollViewer : ScrollViewer
{
public static readonly DependencyProperty SpeedFactorProperty =
DependencyProperty.Register(nameof(SpeedFactor),
typeof(Double),
typeof(WheelSpeedScrollViewer),
new PropertyMetadata(2.5));
public Double SpeedFactor
{
get { return (Double)GetValue(SpeedFactorProperty); }
set { SetValue(SpeedFactorProperty, value); }
}
protected override void OnPreviewMouseWheel(MouseWheelEventArgs e)
{
if (ScrollInfo is ScrollContentPresenter scp &&
ComputedVerticalScrollBarVisibility == Visibility.Visible)
{
scp.SetVerticalOffset(VerticalOffset - e.Delta * SpeedFactor);
e.Handled = true;
}
}
};
以下是大约3200个数据项的“快速鼠标滚轮滚动”的完整XAML演示:
注意:仅用于访问演示数据的“mscorlib”参考。
<UserControl x:Class="RemoveDuplicateTextLines.FastScrollDemo"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:MyApp"
xmlns:sys="clr-namespace:System;assembly=mscorlib">
<local:WheelSpeedScrollViewer VerticalScrollBarVisibility="Auto">
<ListBox ItemsSource="{Binding Source={x:Type sys:Object},Path=Assembly.DefinedTypes}" />
</local:WheelSpeedScrollViewer>
</UserControl>
快速滚轮:
public class VirtualizingScrollSingleItemAtATimeStackPanel : VirtualizingStackPanel
{
public override void MouseWheelDown()
{
PageDown();
}
public override void MouseWheelUp()
{
PageUp();
}
public override void PageDown()
{
LineDown();
}
public override void PageUp()
{
LineUp();
}
}
<ItemsControl>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<controls:VirtualizingScrollSingleItemAtATimeStackPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
public class StepSizeBehavior : Behavior<ScrollViewer>
{
public int StepSize { get; set; }
#region Attach & Detach
protected override void OnAttached()
{
CheckHeightModulesStepSize();
AssociatedObject.ScrollChanged += AssociatedObject_ScrollChanged;
base.OnAttached();
}
protected override void OnDetaching()
{
AssociatedObject.ScrollChanged -= AssociatedObject_ScrollChanged;
base.OnDetaching();
}
#endregion
[Conditional("DEBUG")]
private void CheckHeightModulesStepSize()
{
var height = AssociatedObject.Height;
var remainder = height%StepSize;
if (remainder > 0)
{
throw new ArgumentException($"{nameof(StepSize)} should be set to a value by which the height van be divised without a remainder.");
}
}
private void AssociatedObject_ScrollChanged(object sender, ScrollChangedEventArgs e)
{
const double stepSize = 62;
var scrollViewer = (ScrollViewer)sender;
var steps = Math.Round(scrollViewer.VerticalOffset / stepSize, 0);
var scrollPosition = steps * stepSize;
if (scrollPosition >= scrollViewer.ScrollableHeight)
{
scrollViewer.ScrollToBottom();
return;
}
scrollViewer.ScrollToVerticalOffset(scrollPosition);
}
}
<ScrollViewer MaxHeight="248"
VerticalScrollBarVisibility="Auto">
<i:Interaction.Behaviors>
<behaviors:StepSizeBehavior StepSize="62" />
</i:Interaction.Behaviors>
scrollbar1.Value = Math.Round(scrollbar1.Value, 0, MidpointRounding.AwayFromZero)
<i:Interaction.Behaviors>
。你应该在XAML文档中包含命名空间,问题可能就解决了。关于相关对象,如果你在谷歌上搜索“Behavior.AssociatedObject Property”,你会找到一个MSDN页面。 - Mike de Klerk