protected override IVirtualizedElement <ListViewDataItem> UpdateElement(int position, ListViewDataItem data)
{
IVirtualizedElement <ListViewDataItem> element = null;
object elementContext = this.GetElementContext();
if (position < this.Children.Count)
{
element = (IVirtualizedElement <ListViewDataItem>) this.Children[position];
if (ElementProvider.ShouldUpdate(element, data, elementContext))
{
if (position < this.Children.Count - 1)
{
IVirtualizedElement <ListViewDataItem> nextElement = (IVirtualizedElement <ListViewDataItem>) this.Children[position + 1];
if (nextElement.Data.Equals(data))
{
this.Children.Move(position + 1, position);
nextElement.Synchronize();
return(nextElement);
}
}
if (ElementProvider.IsCompatible(element, data, elementContext))
{
element.Detach();
element.Attach(data, elementContext);
}
else
{
int index = FindCompatibleElement(position, data);
if (index > position)
{
this.Children.Move(index, position);
element = (IVirtualizedElement <ListViewDataItem>) this.Children[position];
element.Detach();
element.Attach(data, elementContext);
}
else
{
position = Math.Min(position, this.Children.Count);
element = ElementProvider.GetElement(data, elementContext);
InsertElement(position, element, data);
}
}
}
}
else
{
position = Math.Min(position, this.Children.Count);
element = ElementProvider.GetElement(data, elementContext);
InsertElement(position, element, data);
}
return(element);
}
public IVirtualizedElement <int> GetElement(int data, object context)
{
bool flag = this.owner.IsRowExpanded(data);
IVirtualizedElement <int> virtualizedElement = (IVirtualizedElement <int>)null;
for (int index = this.cachedRows.Count - 1; index >= 0; --index)
{
if ((!flag && !this.cachedRows[index].IsChildViewInitialized || flag && this.cachedRows[index].IsChildViewInitialized) && this.cachedRows[index].IsCompatible(data, context))
{
virtualizedElement = (IVirtualizedElement <int>) this.cachedRows[index];
this.cachedRows.RemoveAt(index);
break;
}
}
if (virtualizedElement == null && this.cachedRows.Count > 10)
{
for (int index = this.cachedRows.Count - 1; index >= 0; --index)
{
if (this.cachedRows[index].IsCompatible(data, context))
{
virtualizedElement = (IVirtualizedElement <int>) this.cachedRows[index];
this.cachedRows.RemoveAt(index);
break;
}
}
}
if (virtualizedElement == null)
{
VirtualGridRowElement element;
switch (data)
{
case -3:
element = this.CreateElement(data, typeof(VirtualGridFilterRowElement), context);
element.Initialize(this.owner);
element.Attach(-3, context);
break;
case -2:
element = this.CreateElement(data, typeof(VirtualGridNewRowElement), context);
element.Initialize(this.owner);
element.Attach(-2, context);
break;
case -1:
element = this.CreateElement(data, typeof(VirtualGridHeaderRowElement), context);
element.Initialize(this.owner);
element.Attach(-1, context);
break;
default:
element = this.CreateElement(data, typeof(VirtualGridRowElement), context);
element.Initialize(this.owner);
break;
}
return((IVirtualizedElement <int>)element);
}
virtualizedElement.Attach(data, context);
return(virtualizedElement);
}
protected virtual void InsertElement(int position, IVirtualizedElement <T> element, T data)
{
if (element != null)
{
((RadElement)element).Visibility = ElementVisibility.Visible;
this.Children.checkForAlreadyAddedItems = false;
this.Children.Insert(position, (RadElement)element);
this.Children.checkForAlreadyAddedItems = true;
element.Attach(data, GetElementContext());
}
}
public virtual SizeF MeasureItem(Item item, SizeF availableSize)
{
IVirtualizedElement <Item> element = this.ViewElement.ElementProvider.GetElement(item, (object)null);
RadElement radElement = (RadElement)element;
this.SuspendLayout();
this.Children.Add(radElement);
element.Attach(item, (object)null);
radElement.ResetLayout(true);
radElement.Measure(availableSize);
SizeF desiredSize = radElement.GetDesiredSize(false);
this.Children.Remove(radElement);
this.ViewElement.ElementProvider.CacheElement(element);
element.Detach();
this.ResumeLayout(false);
return(desiredSize);
}
public bool TryGetElementWithoutChildView(
int data,
object context,
out IVirtualizedElement <int> element)
{
for (int index = this.cachedRows.Count - 1; index >= 0; --index)
{
if (!this.cachedRows[index].IsChildViewInitialized && this.cachedRows[index].IsCompatible(data, context))
{
element = (IVirtualizedElement <int>) this.cachedRows[index];
this.cachedRows.RemoveAt(index);
element.Attach(data, context);
return(true);
}
}
element = (IVirtualizedElement <int>)null;
return(false);
}