protected IEnumerable <Cell> GetVisibleCells()
{
VirtualizingCellCollection collection = this.ParentPanel.ParentRowCells;
if (collection == null)
{
yield break;
}
foreach (string fieldName in this.GetVisibleFieldsName())
{
yield return(collection.GetCell(fieldName, false));
}
}
private IEnumerable <Cell> GetCellsToLayout(IEnumerable <Cell> visibleCells, IEnumerable <string> permanentScrollingFieldNames, VirtualizingCellCollection cellsCollection)
{
List <string> unhandledCells = permanentScrollingFieldNames.ToList();
foreach (var cell in visibleCells)
{
unhandledCells.Remove(cell.FieldName);
yield return(cell);
}
foreach (var fieldName in unhandledCells)
{
var cell = cellsCollection.GetCell(fieldName, false);
Debug.Assert(cell != null);
yield return(cell);
}
}
private IEnumerable<Cell> GetCellsToLayout( IEnumerable<Cell> visibleCells, IEnumerable<string> permanentScrollingFieldNames, VirtualizingCellCollection cellsCollection )
{
List<string> unhandledCells = permanentScrollingFieldNames.ToList();
foreach( var cell in visibleCells )
{
unhandledCells.Remove( cell.FieldName );
yield return cell;
}
foreach( var fieldName in unhandledCells )
{
var cell = cellsCollection.GetCell( fieldName, false );
Debug.Assert( cell != null );
yield return cell;
}
}
protected Row()
{
this.CommandBindings.Add( new CommandBinding( DataGridCommands.BeginEdit,
new ExecutedRoutedEventHandler( OnBeginEditExecuted ),
new CanExecuteRoutedEventHandler( OnBeginEditCanExecute ) ) );
this.CommandBindings.Add( new CommandBinding( DataGridCommands.EndEdit,
new ExecutedRoutedEventHandler( OnEndEditExecuted ),
new CanExecuteRoutedEventHandler( OnEndEditCanExecute ) ) );
this.CommandBindings.Add( new CommandBinding( DataGridCommands.CancelEdit,
new ExecutedRoutedEventHandler( OnCancelEditExecuted ),
new CanExecuteRoutedEventHandler( OnCancelEditCanExecute ) ) );
// Cache the CellsCollection and always return it in the
// getter of the DependencyProperty's CLR accessor
m_cellsCache = new VirtualizingCellCollection( this );
// Set the Value of the DependencyProperty
this.SetValue( Row.CellsPropertyKey, m_cellsCache );
}
internal static void RemoveListener( VirtualizingCellCollection source, IWeakEventListener listener )
{
VirtualizingCellCollectionChangedEventManager.CurrentManager.ProtectedRemoveListener( source, listener );
}
private void UpdateChildren( DataGridContext dataGridContext, TableViewColumnVirtualizationManagerBase columnVirtualizationManager, VirtualizingCellCollection parentRowCells )
{
//Prevent reentrance
if( ( parentRowCells == null ) || m_parentRowCells.IsUpdating )
return;
using( m_parentRowCells.SetIsUpdating() )
{
this.ClearPermanentScrollingFieldNames();
//Retrieve the cells that aren't needed anymore.
var unusedCells = ( from cell in parentRowCells.BindedCells
where !columnVirtualizationManager.GetScrollingFieldNames( m_parentRow.LevelCache ).Contains( cell.FieldName )
&& !columnVirtualizationManager.GetFixedFieldNames( m_parentRow.LevelCache ).Contains( cell.FieldName )
select cell ).ToList();
//Release the unused binded cells now in order to minimize the number of cell's creation.
foreach( Cell cell in unusedCells )
{
this.AddCellToVisualTree( cell );
if( this.CanReleaseCell( cell ) )
{
// Ensure to close the ContextMenu if it is open and the Cell is virtualized to avoid problems with ContextMenus defined as static resources
// that won't be able to reopen again if the Close private method is called after the PlacementTarget is removed from the VisualTree
var contextMenu = cell.ContextMenu;
if( ( contextMenu != null ) && ( contextMenu.IsOpen ) )
{
contextMenu.IsOpen = false;
}
cell.ClearContainer();
parentRowCells.Release( cell );
}
//Since the cell cannot be released, it will not be collapsed. We must keep the field
//name in order to let the scrolling sub-panel measure and arrange the cell out of view.
else
{
//Certain non recyclable cells like StatCells needs their content binding to be removed when they become out of view.
cell.RemoveContentBinding();
this.AddPermanentScrollingFieldNames( cell.FieldName );
}
}
//Add the missing cells to the fixed region.
foreach( string fieldName in columnVirtualizationManager.GetFixedFieldNames( m_parentRow.LevelCache ) )
{
//The cell is created if it is missing.
Cell cell = parentRowCells[ fieldName ];
//Certain non recyclable cells like StatCells need their content binding to be updated when they become (or stay) in view.
cell.AddContentBinding( dataGridContext, this.ParentRow, this.Columns[ cell.FieldName ] );
//Make sure the cell is in the appropriate panel.
this.MoveCellToFixedPanel( cell );
}
//Add the missing cells to the scrolling region.
foreach( string fieldName in columnVirtualizationManager.GetScrollingFieldNames( m_parentRow.LevelCache ) )
{
//The cell is created if it is missing.
Cell cell = parentRowCells[ fieldName ];
//Certain non recyclable cells like StatCells need their content binding to be updated when they become (or stay) in view.
cell.AddContentBinding( dataGridContext, this.ParentRow, this.Columns[ cell.FieldName ] );
//Make sure the cell is in the appropriate panel.
this.MoveCellToScrollingPanel( cell );
}
if( m_clearUnusedCellsDispatcherOperation == null )
{
m_clearUnusedCellsDispatcherOperation = this.Dispatcher.BeginInvoke( new Action( this.ClearUnusedCells ), DispatcherPriority.ApplicationIdle );
}
m_fixedPanel.InvalidateMeasure();
m_scrollingCellsDecorator.InvalidateMeasure();
m_scrollingPanel.InvalidateMeasure();
}
}
private void UpdateChildren( DataGridContext dataGridContext, TableViewColumnVirtualizationManager columnVirtualizationManager, VirtualizingCellCollection parentRowCells )
{
//Prevent reentrance
if( m_parentRowCells.AlreadyUpdating )
return;
m_parentRowCells.AlreadyUpdating = true;
if( dataGridContext == null )
throw new DataGridInternalException( "DataGridContext is null for FixedCellPanel" );
if( columnVirtualizationManager == null )
throw new DataGridInternalException( "ColumnVirtualizationManager is null for FixedCellPanel" );
if( parentRowCells == null )
return;
this.ClearPermanentScrollingFieldNames();
List<string> currentFieldsName = new List<string>();
currentFieldsName.AddRange( columnVirtualizationManager.FixedFieldNames );
currentFieldsName.AddRange( columnVirtualizationManager.ScrollingFieldNames );
HashSet<Cell> unusedCells = new HashSet<Cell>( parentRowCells.BindedCells );
//Idenfity the binded cells that aren't needed anymore.
foreach( string fieldName in currentFieldsName )
{
ColumnBase column = dataGridContext.Columns[ fieldName ];
Cell cell;
if( parentRowCells.TryGetCell( column, out cell ) )
{
//Certain non recyclable cells like StatCells need their content binding to be updated when they become (or stay) in view.
cell.AddContentBinding();
unusedCells.Remove( cell );
}
}
currentFieldsName.Clear();
currentFieldsName.TrimExcess();
//Release the unused binded cells now in order to minimize the number of cell's creation.
foreach( Cell cell in unusedCells )
{
bool release = this.CanReleaseCell( cell );
//We move the unused cell into the scrolling panel since there is more chance it will be reused there in the future.
this.MoveCellToScrollingPanel( cell, release );
if( release )
{
parentRowCells.Release( cell );
}
//Since the cell cannot be released, it will not be collapsed. We must keep the field name in order to let the scrolling sub-panel measure and arrange the cell out of view.
else
{
//Certain non recyclable cells like StatCells needs their content binding to be removed when they become out of view.
cell.RemoveContentBinding();
this.AddPermanentScrollingFieldNames( cell.FieldName );
}
}
unusedCells.Clear();
unusedCells.TrimExcess();
//Add the missing cells to the fixed region.
foreach( string fieldName in columnVirtualizationManager.FixedFieldNames )
{
//The cell is created if it is missing.
Cell cell = parentRowCells[ fieldName ];
//Make sure the cell is in the appropriate panel.
this.MoveCellToFixedPanel( cell );
}
//Add the missing cells to the scrolling region.
foreach( string fieldName in columnVirtualizationManager.ScrollingFieldNames )
{
//The cell is created if it is missing.
Cell cell = parentRowCells[ fieldName ];
//Make sure the cell is in the appropriate panel.
this.MoveCellToScrollingPanel( cell );
}
if( m_clearUnusedCellsDispatcherOperation == null )
{
m_clearUnusedCellsDispatcherOperation = this.Dispatcher.BeginInvoke( new Action( this.ClearUnusedCells ), DispatcherPriority.ApplicationIdle );
}
m_fixedPanel.InvalidateMeasure();
m_scrollingCellsDecorator.InvalidateMeasure();
m_scrollingPanel.InvalidateMeasure();
m_parentRowCells.AlreadyUpdating = false;
}