static void UpdatePosition(ScrollContentPresenter p, bool highlightOnly)
{
ScrollViewer scrollViewer = UITools.FindAncestor <ScrollViewer>(p);
SelectionAdorner _adorner = GetSelectionAdorner(p);
if (GetIsDragging(p))
{
Point startScrollbarPosition = GetStartScrollbarPosition(p);
Point curScrollbarPosition = GetScrollbarPosition(p);
Point startPosition = GetStartPosition(p);
Point curPosition = Mouse.GetPosition(p);
if (!_adorner.IsSelecting)
{
if (Math.Abs(startPosition.X - curPosition.X) > SystemParameters.MinimumHorizontalDragDistance ||
Math.Abs(startPosition.Y - curPosition.Y) > SystemParameters.MinimumVerticalDragDistance)
{
_adorner.IsSelecting = true;
Mouse.Capture(p);
}
}
else
{
Vector offset = Point.Subtract(startScrollbarPosition, curScrollbarPosition);
_adorner.StartPosition = Point.Add(startPosition, offset);
_adorner.EndPosition = curPosition;
UpdateSelection(p, new Rect(
new Point(startPosition.X + startScrollbarPosition.X, startPosition.Y + startScrollbarPosition.Y),
new Point(curPosition.X + curScrollbarPosition.X, curPosition.Y + curScrollbarPosition.Y)), highlightOnly);
}
}
}
static void EndDragging(ScrollContentPresenter p)
{
SelectionAdorner _adorner = GetSelectionAdorner(p);
if (_adorner.IsSelecting)
{
UpdatePosition(p, false);
_adorner.IsSelecting = false;
SetIsDragging(p, false);
}
}
internal static object PositionCheck(DependencyObject sender, object value)
{
if (value is Point)
{
Point ptValue = (Point)value;
SelectionAdorner adorner = sender as SelectionAdorner;
ptValue.X = Math.Max(ptValue.X, 0);
ptValue.X = Math.Min(ptValue.X, adorner.ActualWidth);
ptValue.Y = Math.Max(ptValue.Y, 0);
ptValue.Y = Math.Min(ptValue.Y, adorner.ActualHeight);
return(ptValue);
}
return(value);
}
public static void OnEnableSelectionpChanged(DependencyObject s, DependencyPropertyChangedEventArgs e)
{
if (s is ListView)
{
ListView control = s as ListView;
var OnScrollChange = (RoutedEventHandler)delegate(object sender, RoutedEventArgs args)
{
ItemsPresenter ip = UITools.FindVisualChild<ItemsPresenter>(sender as ListView);
ScrollContentPresenter p = UITools.FindAncestor<ScrollContentPresenter>(ip);
if (GetIsDragging(p) && Mouse.LeftButton == MouseButtonState.Pressed)
UpdatePosition(p, true);
};
var OnMouseDown = (RoutedEventHandler)delegate(object sender, RoutedEventArgs args)
{
ClearSelection(sender as ListView);
};
var OnSizeChanged = (RoutedEventHandler)delegate(object sender, RoutedEventArgs args)
{
ItemsPresenter ip = UITools.FindVisualChild<ItemsPresenter>(sender as ListView);
ScrollContentPresenter p = UITools.FindAncestor<ScrollContentPresenter>(ip);
EndDragging(p);
};
Action unloadAdorner = () =>
{
ScrollContentPresenter p = GetLastScrollContentPresenter(control);
if (p != null)
{
SelectionAdorner _adorner = GetSelectionAdorner(p);
if (AdornerLayer.GetAdornerLayer(p) != null)
AdornerLayer.GetAdornerLayer(p).Remove(_adorner);
control.MouseUp -= new MouseButtonEventHandler(OnMouseUp);
control.MouseMove -= new MouseEventHandler(OnMouseMove);
_adorner.PreviewMouseDown -= new MouseButtonEventHandler(OnPreviewMouseDown);
_adorner.MouseMove -= new MouseEventHandler(OnMouseMove);
_adorner.MouseUp -= new MouseButtonEventHandler(OnMouseUp);
control.RemoveHandler(ListView.SizeChangedEvent, OnSizeChanged);
SetSelectionAdorner(p, null);
}
};
Action attachAdorner = () =>
{
unloadAdorner();
ItemsPresenter ip = UITools.FindVisualChild<ItemsPresenter>(control);
ScrollContentPresenter p = UITools.FindAncestor<ScrollContentPresenter>(ip);
if (p != null)
{
SelectionAdorner _adorner = new SelectionAdorner(p);
SetSelectionAdorner(p, _adorner);
AdornerLayer.GetAdornerLayer(p).Add(_adorner);
control.PreviewMouseDown += new MouseButtonEventHandler(OnPreviewMouseDown);
control.MouseUp += new MouseButtonEventHandler(OnMouseUp);
control.MouseMove += new MouseEventHandler(OnMouseMove);
_adorner.PreviewMouseDown += new MouseButtonEventHandler(OnPreviewMouseDown);
_adorner.MouseMove += new MouseEventHandler(OnMouseMove);
_adorner.MouseUp += new MouseButtonEventHandler(OnMouseUp);
control.AddHandler(ListView.SizeChangedEvent, OnSizeChanged);
SetLastScrollContentPresenter(control, p);
}
};
if ((bool)e.NewValue == true)
{
if (control.IsLoaded)
attachAdorner();
else
control.Loaded += delegate { attachAdorner(); };
control.AddHandler(ScrollViewer.ScrollChangedEvent, OnScrollChange);
control.AddHandler(ListView.MouseDownEvent, OnMouseDown);
//Monitor view change, and reattach handlers.
DependencyPropertyDescriptor viewDescriptor = DependencyPropertyDescriptor.FromProperty(ListView.ViewProperty, typeof(ListView));
viewDescriptor.AddValueChanged
(control, delegate
{
control.Dispatcher.BeginInvoke(DispatcherPriority.Input, attachAdorner);
});
}
else //If EnableSelection = False
{
unloadAdorner();
control.RemoveHandler(ScrollViewer.ScrollChangedEvent, OnScrollChange);
control.RemoveHandler(ListView.MouseDownEvent, OnMouseDown);
SetSelectionAdorner(control, null);
}
}
}
public static void SetSelectionAdorner(DependencyObject target, SelectionAdorner value)
{
target.SetValue(SelectionAdornerProperty, value);
}
public static void SetSelectionAdorner(DependencyObject target, SelectionAdorner value)
{
target.SetValue(SelectionAdornerProperty, value);
}
public static void OnEnableSelectionpChanged(DependencyObject s, DependencyPropertyChangedEventArgs e)
{
if (s is ListView)
{
ListView control = s as ListView;
var OnSizeChanged = (RoutedEventHandler) delegate(object sender, RoutedEventArgs args)
{
ItemsPresenter ip = UITools.FindVisualChild <ItemsPresenter>(sender as ListView);
ScrollContentPresenter p = UITools.FindAncestor <ScrollContentPresenter>(ip);
EndDragging(p);
};
Func <ScrollContentPresenter, AdornerLayer> getAdornerLayer = (p) =>
{
AdornerLayer adornerLayer = AdornerLayer.GetAdornerLayer(p);
if (adornerLayer != null)
{
return(adornerLayer);
}
ItemsPresenter ip = UITools.FindVisualChild <ItemsPresenter>(s as ListView);
AdornerDecorator ad = UITools.FindAncestor <AdornerDecorator>(ip);
try
{
adornerLayer = AdornerLayer.GetAdornerLayer(ad);
if (adornerLayer != null)
{
return(adornerLayer);
}
}
catch { }
return(p.AdornerLayer);;
};
Action unloadAdorner = () =>
{
ScrollContentPresenter p = GetLastScrollContentPresenter(control);
if (p != null)
{
SelectionAdorner _adorner = GetSelectionAdorner(p);
if (_adorner != null)
{
getAdornerLayer(p).Remove(_adorner);
_adorner.PreviewMouseDown -= new MouseButtonEventHandler(OnPreviewMouseDown);
_adorner.MouseMove -= new MouseEventHandler(OnMouseMove);
_adorner.MouseUp -= new MouseButtonEventHandler(OnMouseUp);
}
control.MouseUp -= new MouseButtonEventHandler(OnMouseUp);
control.MouseMove -= new MouseEventHandler(OnMouseMove);
control.RemoveHandler(ListView.SizeChangedEvent, OnSizeChanged);
SetSelectionAdorner(p, null);
}
};
Action attachAdorner = () =>
{
unloadAdorner();
ItemsPresenter ip = UITools.FindVisualChild <ItemsPresenter>(control);
ScrollContentPresenter p = UITools.FindAncestor <ScrollContentPresenter>(ip);
if (p != null)
{
SelectionAdorner _adorner = new SelectionAdorner(p);
SetSelectionAdorner(p, _adorner);
AdornerLayer adornerLayer = getAdornerLayer(p);
if (adornerLayer != null)
{
adornerLayer.Add(_adorner);
_adorner.PreviewMouseDown += new MouseButtonEventHandler(OnPreviewMouseDown);
_adorner.MouseMove += new MouseEventHandler(OnMouseMove);
_adorner.MouseUp += new MouseButtonEventHandler(OnMouseUp);
}
control.PreviewMouseDown += new MouseButtonEventHandler(OnPreviewMouseDown);
control.MouseUp += new MouseButtonEventHandler(OnMouseUp);
control.MouseMove += new MouseEventHandler(OnMouseMove);
control.AddHandler(ListView.SizeChangedEvent, OnSizeChanged);
SetLastScrollContentPresenter(control, p);
}
};
if ((bool)e.NewValue == true)
{
if (control.IsLoaded)
{
attachAdorner();
}
else
{
control.Loaded += delegate { attachAdorner(); }
};
control.AddHandler(ScrollViewer.ScrollChangedEvent, new RoutedEventHandler(OnScrollChange));
control.AddHandler(ListView.MouseDownEvent, new RoutedEventHandler(OnMouseDown));
//Monitor view change, and reattach handlers.
DependencyPropertyDescriptor viewDescriptor = DependencyPropertyDescriptor.FromProperty(ListView.ViewProperty, typeof(ListView));
viewDescriptor.AddValueChanged
(control, delegate
{
control.Dispatcher.BeginInvoke(DispatcherPriority.Input, attachAdorner);
});
}
else //If EnableSelection = False
{
unloadAdorner();
control.RemoveHandler(ScrollViewer.ScrollChangedEvent, new RoutedEventHandler(OnScrollChange));
control.RemoveHandler(ListView.MouseDownEvent, new RoutedEventHandler(OnMouseDown));
SetSelectionAdorner(control, null);
}
}
}
