private bool TryGetRecycledCell(ColumnBase column, out Cell cell)
{
cell = null;
if (m_recyclingBins == null)
{
return(false);
}
// Make sure the cell recycling group is up-to-date.
var dataGridContext = this.DataGridContext;
if (dataGridContext != null)
{
var propertyDescription = ItemsSourceHelper.CreateOrGetPropertyDescriptionFromColumn(dataGridContext, column, null);
ItemsSourceHelper.UpdateColumnFromPropertyDescription(column, dataGridContext.DataGridControl.DefaultCellEditors, dataGridContext.AutoCreateForeignKeyConfigurations, propertyDescription);
}
var recyclingGroup = this.GetRecyclingGroup(column);
var recycleBin = default(LinkedList <Cell>);
if (m_recyclingBins.TryGetValue(recyclingGroup, out recycleBin))
{
// Try to recycle a cell that has already the appropriate column in order to minimize the cell's initialization time.
var targetNode = default(LinkedListNode <Cell>);
for (var node = recycleBin.Last; node != null; node = node.Previous)
{
targetNode = node;
if (targetNode.Value.ParentColumn == column)
{
break;
}
}
// From here, the target node is either:
// 1. The cell with minimal initialization time.
// 2. The oldest cell.
// 3. null in case of an empty bin.
if (targetNode != null)
{
cell = targetNode.Value;
recycleBin.Remove(targetNode);
}
}
return(cell != null);
}
protected internal virtual void SetupDisplayMemberBinding(DataGridContext dataGridContext)
{
// Bind the cell content.
var column = this.ParentColumn as Column;
if (column != null)
{
var displayMemberBinding = default(BindingBase);
var dataItem = this.ParentRow.DataContext;
// If the dataContext is our ParentRow, we do not create any binding
if (dataItem != this.ParentRow)
{
displayMemberBinding = column.GetDisplayMemberBinding();
if (displayMemberBinding == null)
{
if (dataGridContext == null)
{
throw new InvalidOperationException("An attempt was made to create a DisplayMemberBinding before the DataGridContext has been initialized.");
}
if (!DesignerProperties.GetIsInDesignMode(this))
{
var propertyDescription = ItemsSourceHelper.CreateOrGetPropertyDescriptionFromColumn(dataGridContext, column, (dataItem != null) ? dataItem.GetType() : null);
ItemsSourceHelper.UpdateColumnFromPropertyDescription(column, dataGridContext.DataGridControl.DefaultCellEditors, dataGridContext.AutoCreateForeignKeyConfigurations, propertyDescription);
displayMemberBinding = column.GetDisplayMemberBinding();
}
column.IsBindingAutoCreated = true;
}
}
if (displayMemberBinding != null)
{
m_canBeRecycled = DataCell.VerifyDisplayMemberBinding(displayMemberBinding);
BindingOperations.SetBinding(this, Cell.ContentProperty, displayMemberBinding);
var xmlElement = this.GetValue(Cell.ContentProperty) as XmlElement;
if (xmlElement != null)
{
// Convert binding to an InnerXML binding in the case we are bound on a XmlElement
// to be able to refresh the data in the XML.
//under any circumstances, a cell that is bound to XML cannot be recycled
m_canBeRecycled = false;
this.ClearDisplayMemberBinding();
var xmlElementBinding = new Binding("InnerXml");
xmlElementBinding.Source = xmlElement;
xmlElementBinding.Mode = BindingMode.TwoWay;
xmlElementBinding.UpdateSourceTrigger = UpdateSourceTrigger.Explicit;
BindingOperations.SetBinding(this, Cell.ContentProperty, xmlElementBinding);
}
}
else
{
this.ClearDisplayMemberBinding();
}
}
else
{
this.ClearDisplayMemberBinding();
}
}