protected override void OnMouseLeftButtonDown(MouseButtonEventArgs e)
{
base.OnMouseLeftButtonDown(e);
adorner = new RectAdorner(this);
adorner.Origin = e.GetPosition(this);
adorner.Show();
Mouse.Capture(this);
}
protected override void OnPreviewMouseLeftButtonUp(MouseButtonEventArgs e)
{
base.OnPreviewMouseLeftButtonUp(e);
if (Mouse.Captured == null)
{
return;
}
Mouse.Capture(null);
adorner.Hide();
var origin = adorner.Origin;
var dest = adorner.Destination;
adorner = null;
List <MyMultiSelecterItem> hitItems = new List <MyMultiSelecterItem>();
VisualTreeHelper.HitTest(
this,
new HitTestFilterCallback((d) =>
{
if (d is MyMultiSelecterItem)
{
return(HitTestFilterBehavior.ContinueSkipChildren);
}
else
{
return(HitTestFilterBehavior.ContinueSkipSelf);
}
}),
new HitTestResultCallback((result) =>
{
var geometryResult = result as GeometryHitTestResult;
if (geometryResult == null)
{
return(HitTestResultBehavior.Continue);
}
if (geometryResult.IntersectionDetail != IntersectionDetail.Empty)
{
hitItems.Add(geometryResult.VisualHit as MyMultiSelecterItem);
}
return(HitTestResultBehavior.Continue);
}),
new GeometryHitTestParameters(new RectangleGeometry(new Rect(origin, dest))));
var oldSelectedVMs = SelectedItems.OfType <object>().ToList();
BeginUpdateSelectedItems();
SelectedItems.Clear();
foreach (var item in hitItems)
{
SelectedItems.Add(ItemContainerGenerator.ItemFromContainer(item));
}
foreach (var oldSelectedVM in oldSelectedVMs)
{
var oldSelected = ItemContainerGenerator.ContainerFromItem(oldSelectedVM) as MyMultiSelecterItem;
if (oldSelected != null)
{
oldSelected.IsSelected = false;
}
}
foreach (var selected in hitItems)
{
selected.IsSelected = true;
}
EndUpdateSelectedItems();
}
