问题描述
||
我正在编写自定义WPF ItemsControl以显示项目列表。这些项目显示为嵌入ScrollViewer内部:
<Style targettype=\"MyCustomItemsControl\">
<Setter Property=\"Template\">
<Setter.Value>
<ControlTemplate targettype=\"MyCustomItemsControl\">
<ScrollViewer x:Name=\"PART_MyScrollViewer\" >
<ItemsPresenter/>
</ScrollViewer>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
我想确保当我将鼠标移到控件中时,特定项目(标记为选中)将滚动到鼠标位置。在我的OnMouseEnter方法中,我可以找到该项目,但是我不知道下一步该怎么做。有人有什么主意吗?
protected override void OnMouseEnter(MouseEventArgs e)
{
for (int i = 0; i < Items.Count; i++)
{
ContentPresenter uiElement = (ContentPresenter)ItemContainerGenerator.ContainerFromIndex(i);
var item = uiElement.Content as MyCustomObject;
if (item.IsSelected)
{
// How to scroll the uiElement to the mouse position?
break;
}
}
}
解决方法
类似于以下内容:
var sv = (ScrollViewer)Template.FindName(\"PART_MyScrollViewer\",this); // If you do not already have a reference to it somewhere.
var ip = (ItemsPresenter)sv.Content;
var point = item.TranslatePoint(new Point() - (Vector)e.GetPosition(sv),ip);
sv.ScrollToVerticalOffset(point.Y + (item.ActualHeight / 2));
, // How to scroll the uiElement to the mouse position?
uiElement.BringIntoView();
参考:https://msdn.microsoft.com/zh-cn/library/ms598110.aspx
更新:(由于@jmbpiano)请注意,它不能将控件完全移到当前鼠标光标位置。它只是将控件移到可见位置,操作员可以在其中单击鼠标(在99%的情况下,发现这个问题的人可能都需要使用该控件)。
, 使用UIElement.TranslatePoint()计算要滚动到的位置
使用ScrollViewer.ScrollToVerticalOffset()进行滚动
, 试试下面的代码:
private void ScrollViewerFromVSTree(DependencyObject element,double pos)
{
try
{
int totalElementcount = VisualTreeHelper.GetChildrenCount(element);
for (int counter = 0; counter < totalElementcount; counter++)
{
DependencyObject ele = VisualTreeHelper.GetChild(element,counter);
if (ele.GetType().Name == \"ScrollViewer\")
{
ScrollViewer scrollViewer = ele as ScrollViewer;
if (pos > \"YourAssumption\") // for me it is 610
{
scrollViewer.ScrollToVerticalOffset(scrollViewer.VerticalOffset + 45);
}
else if (pos < \"YourAssumption\") //for me it is 40
{
scrollViewer.ScrollToVerticalOffset(scrollViewer.VerticalOffset - 45);
}
break;
}
ScrollViewerFromVSTree(VisualTreeHelper.GetChild(element,counter),pos);
}
}
catch (Exception)
{
}
}