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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Windows.Automation;
using System.Windows.Automation.Peers;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Threading;
using MS.Internal;
namespace System.Windows.Controls
{
/// <summary>
/// A control for displaying a row of the DataGrid.
/// A row represents a data item in the DataGrid.
/// A row displays a cell for each column of the DataGrid.
///
/// The data item for the row is added n times to the row's Items collection,
/// where n is the number of columns in the DataGrid.
/// </summary>
public class DataGridRow : Control
{
#region Constants
private const byte DATAGRIDROW_stateMouseOverCode = 0;
private const byte DATAGRIDROW_stateMouseOverEditingCode = 1;
private const byte DATAGRIDROW_stateMouseOverEditingFocusedCode = 2;
private const byte DATAGRIDROW_stateMouseOverSelectedCode = 3;
private const byte DATAGRIDROW_stateMouseOverSelectedFocusedCode = 4;
private const byte DATAGRIDROW_stateNormalCode = 5;
private const byte DATAGRIDROW_stateNormalEditingCode = 6;
private const byte DATAGRIDROW_stateNormalEditingFocusedCode = 7;
private const byte DATAGRIDROW_stateSelectedCode = 8;
private const byte DATAGRIDROW_stateSelectedFocusedCode = 9;
private const byte DATAGRIDROW_stateNullCode = 255;
// Static arrays to handle state transitions:
private static ReadOnlySpan<byte> IdealStateMapping => [
DATAGRIDROW_stateNormalCode,
DATAGRIDROW_stateNormalCode,
DATAGRIDROW_stateMouseOverCode,
DATAGRIDROW_stateMouseOverCode,
DATAGRIDROW_stateNullCode,
DATAGRIDROW_stateNullCode,
DATAGRIDROW_stateNullCode,
DATAGRIDROW_stateNullCode,
DATAGRIDROW_stateSelectedCode,
DATAGRIDROW_stateSelectedFocusedCode,
DATAGRIDROW_stateMouseOverSelectedCode,
DATAGRIDROW_stateMouseOverSelectedFocusedCode,
DATAGRIDROW_stateNormalEditingCode,
DATAGRIDROW_stateNormalEditingFocusedCode,
DATAGRIDROW_stateMouseOverEditingCode,
DATAGRIDROW_stateMouseOverEditingFocusedCode
];
private static ReadOnlySpan<byte> FallbackStateMapping => [
DATAGRIDROW_stateNormalCode, //DATAGRIDROW_stateMouseOverCode's fallback
DATAGRIDROW_stateMouseOverEditingFocusedCode, //DATAGRIDROW_stateMouseOverEditingCode's fallback
DATAGRIDROW_stateNormalEditingFocusedCode, //DATAGRIDROW_stateMouseOverEditingFocusedCode's fallback
DATAGRIDROW_stateMouseOverSelectedFocusedCode, //DATAGRIDROW_stateMouseOverSelectedCode's fallback
DATAGRIDROW_stateSelectedFocusedCode, //DATAGRIDROW_stateMouseOverSelectedFocusedCode's fallback
DATAGRIDROW_stateNullCode, //DATAGRIDROW_stateNormalCode's fallback
DATAGRIDROW_stateNormalEditingFocusedCode, //DATAGRIDROW_stateNormalEditingCode's fallback
DATAGRIDROW_stateSelectedFocusedCode, //DATAGRIDROW_stateNormalEditingFocusedCode's fallback
DATAGRIDROW_stateSelectedFocusedCode, //DATAGRIDROW_stateSelectedCode's fallback
DATAGRIDROW_stateNormalCode //DATAGRIDROW_stateSelectedFocusedCode's fallback
];
private static string[] _stateNames = new string[] {
VisualStates.DATAGRIDROW_stateMouseOver,
VisualStates.DATAGRIDROW_stateMouseOverEditing,
VisualStates.DATAGRIDROW_stateMouseOverEditingFocused,
VisualStates.DATAGRIDROW_stateMouseOverSelected,
VisualStates.DATAGRIDROW_stateMouseOverSelectedFocused,
VisualStates.DATAGRIDROW_stateNormal,
VisualStates.DATAGRIDROW_stateNormalEditing,
VisualStates.DATAGRIDROW_stateNormalEditingFocused,
VisualStates.DATAGRIDROW_stateSelected,
VisualStates.DATAGRIDROW_stateSelectedFocused
};
#endregion Constants
#region Constructors
/// <summary>
/// Instantiates global information.
/// </summary>
static DataGridRow()
{
VisibilityProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnCoerceVisibility));
DefaultStyleKeyProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(typeof(DataGridRow)));
ItemsPanelProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(new ItemsPanelTemplate(new FrameworkElementFactory(typeof(DataGridCellsPanel)))));
FocusableProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(false));
BackgroundProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyRowPropertyChanged, OnCoerceBackground));
BindingGroupProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(OnNotifyRowPropertyChanged));
// Set SnapsToDevicePixels to true so that this element can draw grid lines. The metadata options are so that the property value doesn't inherit down the tree from here.
SnapsToDevicePixelsProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(true, FrameworkPropertyMetadataOptions.AffectsArrange));
IsMouseOverPropertyKey.OverrideMetadata(typeof(DataGridRow), new UIPropertyMetadata(new PropertyChangedCallback(OnNotifyRowAndRowHeaderPropertyChanged)));
VirtualizingPanel.ShouldCacheContainerSizeProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(null, new CoerceValueCallback(OnCoerceShouldCacheContainerSize)));
AutomationProperties.IsOffscreenBehaviorProperty.OverrideMetadata(typeof(DataGridRow), new FrameworkPropertyMetadata(IsOffscreenBehavior.FromClip));
}
/// <summary>
/// Instantiates a new instance of this class.
/// </summary>
public DataGridRow()
{
_tracker = new ContainerTracking<DataGridRow>(this);
}
#endregion
#region Data Item
/// <summary>
/// The item that the row represents. This item is an entry in the list of items from the DataGrid.
/// From this item, cells are generated for each column in the DataGrid.
/// </summary>
public object Item
{
get { return GetValue(ItemProperty); }
set { SetValue(ItemProperty, value); }
}
/// <summary>
/// The DependencyProperty for the Item property.
/// </summary>
public static readonly DependencyProperty ItemProperty =
DependencyProperty.Register("Item", typeof(object), typeof(DataGridRow), new FrameworkPropertyMetadata(null, new PropertyChangedCallback(OnNotifyRowPropertyChanged)));
/// <summary>
/// Called when the value of the Item property changes.
/// </summary>
/// <param name="oldItem">The old value of Item.</param>
/// <param name="newItem">The new value of Item.</param>
protected virtual void OnItemChanged(object oldItem, object newItem)
{
DataGridCellsPresenter cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
cellsPresenter.Item = newItem;
}
}
#endregion
#region Template
/// <summary>
/// A template that will generate the panel that arranges the cells in this row.
/// </summary>
/// <remarks>
/// The template for the row should contain an ItemsControl that template binds to this property.
/// </remarks>
public ItemsPanelTemplate ItemsPanel
{
get { return (ItemsPanelTemplate)GetValue(ItemsPanelProperty); }
set { SetValue(ItemsPanelProperty, value); }
}
/// <summary>
/// The DependencyProperty that represents the ItemsPanel property.
/// </summary>
public static readonly DependencyProperty ItemsPanelProperty = ItemsControl.ItemsPanelProperty.AddOwner(typeof(DataGridRow));
/// <summary>
/// Clears the CellsPresenter and DetailsPresenter references on Template change.
/// </summary>
protected override void OnTemplateChanged(ControlTemplate oldTemplate, ControlTemplate newTemplate)
{
base.OnTemplateChanged(oldTemplate, newTemplate);
CellsPresenter = null;
DetailsPresenter = null;
}
#endregion
#region Visual States
private bool IsDataGridKeyboardFocusWithin
{
get
{
var dataGrid = DataGridOwner;
if (dataGrid != null)
{
return dataGrid.IsKeyboardFocusWithin;
}
return false;
}
}
/// <summary>
/// Updates the background brush of the row, using a storyboard if available.
/// </summary>
internal override void ChangeVisualState(bool useTransitions)
{
byte idealStateMappingIndex = 0;
if (IsSelected || IsEditing) // this is slightly different than SL because they assume if it's editing it will be selected.
{
idealStateMappingIndex += 8;
}
if (IsEditing)
{
idealStateMappingIndex += 4;
}
if (IsMouseOver)
{
idealStateMappingIndex += 2;
}
if (IsDataGridKeyboardFocusWithin)
{
idealStateMappingIndex += 1;
}
byte stateCode = IdealStateMapping[idealStateMappingIndex];
Debug.Assert(stateCode != DATAGRIDROW_stateNullCode);
string storyboardName;
while (stateCode != DATAGRIDROW_stateNullCode)
{
if (stateCode == DATAGRIDROW_stateNormalCode)
{
if (AlternationIndex % 2 == 1)
{
storyboardName = VisualStates.DATAGRIDROW_stateAlternate;
}
else
{
storyboardName = VisualStates.DATAGRIDROW_stateNormal;
}
}
else
{
storyboardName = _stateNames[stateCode];
}
if (VisualStateManager.GoToState(this, storyboardName, useTransitions))
{
break;
}
else
{
// The state wasn't implemented so fall back to the next one
stateCode = FallbackStateMapping[stateCode];
}
}
base.ChangeVisualState(useTransitions);
}
#endregion
#region Row Header
/// <summary>
/// The object representing the Row Header.
/// </summary>
public object Header
{
get { return GetValue(HeaderProperty); }
set { SetValue(HeaderProperty, value); }
}
/// <summary>
/// The DependencyProperty for the Header property.
/// </summary>
public static readonly DependencyProperty HeaderProperty =
DependencyProperty.Register("Header", typeof(object), typeof(DataGridRow), new FrameworkPropertyMetadata(null, new PropertyChangedCallback(OnNotifyRowAndRowHeaderPropertyChanged)));
/// <summary>
/// Called when the value of the Header property changes.
/// </summary>
/// <param name="oldHeader">The old value of Header</param>
/// <param name="newHeader">The new value of Header</param>
protected virtual void OnHeaderChanged(object oldHeader, object newHeader)
{
}
/// <summary>
/// The object representing the Row Header style.
/// </summary>
public Style HeaderStyle
{
get { return (Style)GetValue(HeaderStyleProperty); }
set { SetValue(HeaderStyleProperty, value); }
}
/// <summary>
/// The DependencyProperty for the HeaderStyle property.
/// </summary>
public static readonly DependencyProperty HeaderStyleProperty =
DependencyProperty.Register("HeaderStyle", typeof(Style), typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyRowAndRowHeaderPropertyChanged, OnCoerceHeaderStyle));
/// <summary>
/// The object representing the Row Header template.
/// </summary>
public DataTemplate HeaderTemplate
{
get { return (DataTemplate)GetValue(HeaderTemplateProperty); }
set { SetValue(HeaderTemplateProperty, value); }
}
/// <summary>
/// The DependencyProperty for the HeaderTemplate property.
/// </summary>
public static readonly DependencyProperty HeaderTemplateProperty =
DependencyProperty.Register("HeaderTemplate", typeof(DataTemplate), typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyRowAndRowHeaderPropertyChanged, OnCoerceHeaderTemplate));
/// <summary>
/// The object representing the Row Header template selector.
/// </summary>
public DataTemplateSelector HeaderTemplateSelector
{
get { return (DataTemplateSelector)GetValue(HeaderTemplateSelectorProperty); }
set { SetValue(HeaderTemplateSelectorProperty, value); }
}
/// <summary>
/// The DependencyProperty for the HeaderTemplateSelector property.
/// </summary>
public static readonly DependencyProperty HeaderTemplateSelectorProperty =
DependencyProperty.Register("HeaderTemplateSelector", typeof(DataTemplateSelector), typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyRowAndRowHeaderPropertyChanged, OnCoerceHeaderTemplateSelector));
/// <summary>
/// Template used to visually indicate an error in row Validation.
/// </summary>
public ControlTemplate ValidationErrorTemplate
{
get { return (ControlTemplate)GetValue(ValidationErrorTemplateProperty); }
set { SetValue(ValidationErrorTemplateProperty, value); }
}
/// <summary>
/// DependencyProperty for the ValidationErrorTemplate property.
/// </summary>
public static readonly DependencyProperty ValidationErrorTemplateProperty =
DependencyProperty.Register("ValidationErrorTemplate", typeof(ControlTemplate), typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyRowPropertyChanged, OnCoerceValidationErrorTemplate));
#endregion
#region Row Details
/// <summary>
/// The object representing the Row Details template.
/// </summary>
public DataTemplate DetailsTemplate
{
get { return (DataTemplate)GetValue(DetailsTemplateProperty); }
set { SetValue(DetailsTemplateProperty, value); }
}
/// <summary>
/// The DependencyProperty for the DetailsTemplate property.
/// </summary>
public static readonly DependencyProperty DetailsTemplateProperty =
DependencyProperty.Register("DetailsTemplate", typeof(DataTemplate), typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyDetailsTemplatePropertyChanged, OnCoerceDetailsTemplate));
/// <summary>
/// The object representing the Row Details template selector.
/// </summary>
public DataTemplateSelector DetailsTemplateSelector
{
get { return (DataTemplateSelector)GetValue(DetailsTemplateSelectorProperty); }
set { SetValue(DetailsTemplateSelectorProperty, value); }
}
/// <summary>
/// The DependencyProperty for the DetailsTemplateSelector property.
/// </summary>
public static readonly DependencyProperty DetailsTemplateSelectorProperty =
DependencyProperty.Register("DetailsTemplateSelector", typeof(DataTemplateSelector), typeof(DataGridRow), new FrameworkPropertyMetadata(null, OnNotifyDetailsTemplatePropertyChanged, OnCoerceDetailsTemplateSelector));
/// <summary>
/// The Visibility of the Details presenter
/// </summary>
public Visibility DetailsVisibility
{
get { return (Visibility)GetValue(DetailsVisibilityProperty); }
set { SetValue(DetailsVisibilityProperty, value); }
}
/// <summary>
/// The DependencyProperty for the DetailsVisibility property.
/// </summary>
public static readonly DependencyProperty DetailsVisibilityProperty =
DependencyProperty.Register("DetailsVisibility", typeof(Visibility), typeof(DataGridRow), new FrameworkPropertyMetadata(Visibility.Collapsed, OnNotifyDetailsVisibilityChanged, OnCoerceDetailsVisibility));
internal bool DetailsLoaded
{
get
{
return _detailsLoaded;
}
set
{
_detailsLoaded = value;
}
}
#endregion
#region Row Generation
/// <summary>
/// We can't override the metadata for a read only property, so we'll get the property change notification for AlternationIndexProperty this way instead.
/// </summary>
protected override void OnPropertyChanged(DependencyPropertyChangedEventArgs e)
{
base.OnPropertyChanged(e);
if (e.Property == AlternationIndexProperty)
{
NotifyPropertyChanged(this, e, DataGridNotificationTarget.Rows);
}
}
/// <summary>
/// Prepares a row container for active use.
/// </summary>
/// <remarks>
/// Instantiates or updates a MultipleCopiesCollection ItemsSource in
/// order that cells be generated.
/// </remarks>
/// <param name="item">The data item that the row represents.</param>
/// <param name="owningDataGrid">The DataGrid owner.</param>
internal void PrepareRow(object item, DataGrid owningDataGrid)
{
bool fireOwnerChanged = (_owner != owningDataGrid);
Debug.Assert(_owner == null || _owner == owningDataGrid, "_owner should be null before PrepareRow is called or the same as the owningDataGrid.");
bool forcePrepareCells = false;
_owner = owningDataGrid;
if (this != item)
{
if (Item != item)
{
Item = item;
}
else
{
forcePrepareCells = true;
}
}
if (IsEditing)
{
// If IsEditing was left on and this container was recycled, reset it here.
IsEditing = false;
}
// Since we just changed _owner we need to invalidate all child properties that rely on a value supplied by the DataGrid.
// A common scenario is when a recycled Row was detached from the visual tree and has just been reattached (we always clear out the
// owner when recycling a container).
if (fireOwnerChanged)
{
SyncProperties(forcePrepareCells);
}
CoerceValue(VirtualizingPanel.ShouldCacheContainerSizeProperty);
// Re-run validation, but wait until Binding has occured.
Dispatcher.BeginInvoke(new DispatcherOperationCallback(DelayedValidateWithoutUpdate), DispatcherPriority.DataBind, BindingGroup);
}
/// <summary>
/// Clears the row of references.
/// </summary>
internal void ClearRow(DataGrid owningDataGrid)
{
Debug.Assert(_owner == owningDataGrid, "_owner should be the same as the DataGrid that is clearing the row.");
var cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
PersistAttachedItemValue(cellsPresenter, DataGridCellsPresenter.HeightProperty);
}
PersistAttachedItemValue(this, DetailsVisibilityProperty);
Item = BindingExpressionBase.DisconnectedItem;
DataGridDetailsPresenter detailsPresenter = DetailsPresenter;
if (detailsPresenter != null)
{
detailsPresenter.Content = BindingExpressionBase.DisconnectedItem;
}
_owner = null;
}
private void PersistAttachedItemValue(DependencyObject objectWithProperty, DependencyProperty property)
{
ValueSource valueSource = DependencyPropertyHelper.GetValueSource(objectWithProperty, property);
if (valueSource.BaseValueSource == BaseValueSource.Local)
{
// attach the local value to the item so it can be restored later.
_owner.ItemAttachedStorage.SetValue(Item, property, objectWithProperty.GetValue(property));
objectWithProperty.ClearValue(property);
}
}
private void RestoreAttachedItemValue(DependencyObject objectWithProperty, DependencyProperty property)
{
object value;
if (_owner.ItemAttachedStorage.TryGetValue(Item, property, out value))
{
objectWithProperty.SetValue(property, value);
}
}
/// <summary>
/// Used by the DataGrid owner to send notifications to the row container.
/// </summary>
internal ContainerTracking<DataGridRow> Tracker
{
get { return _tracker; }
}
#endregion
#region Row Resizing
internal void OnRowResizeStarted()
{
var cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
_cellsPresenterResizeHeight = cellsPresenter.Height;
}
}
internal void OnRowResize(double changeAmount)
{
var cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
double newHeight = cellsPresenter.ActualHeight + changeAmount;
// clamp the CellsPresenter size to the RowHeader size or MinHeight because the header wont shrink any smaller.
double minHeight = Math.Max(RowHeader.DesiredSize.Height, MinHeight);
if (DoubleUtil.LessThan(newHeight, minHeight))
{
newHeight = minHeight;
}
// clamp the CellsPresenter size to the MaxHeight of Row, because row wouldn't grow any larger
double maxHeight = MaxHeight;
if (DoubleUtil.GreaterThan(newHeight, maxHeight))
{
newHeight = maxHeight;
}
cellsPresenter.Height = newHeight;
}
}
internal void OnRowResizeCompleted(bool canceled)
{
var cellsPresenter = CellsPresenter;
if (cellsPresenter != null && canceled)
{
cellsPresenter.Height = _cellsPresenterResizeHeight;
}
}
internal void OnRowResizeReset()
{
var cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
cellsPresenter.ClearValue(DataGridCellsPresenter.HeightProperty);
if (_owner != null)
{
_owner.ItemAttachedStorage.ClearValue(Item, DataGridCellsPresenter.HeightProperty);
}
}
}
#endregion
#region Columns Notification
/// <summary>
/// Notification from the DataGrid that the columns collection has changed.
/// </summary>
/// <param name="columns">The columns collection.</param>
/// <param name="e">The event arguments from the collection's change event.</param>
protected internal virtual void OnColumnsChanged(ObservableCollection<DataGridColumn> columns, NotifyCollectionChangedEventArgs e)
{
DataGridCellsPresenter cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
cellsPresenter.OnColumnsChanged(columns, e);
}
}
#endregion
#region Property Coercion
private static object OnCoerceHeaderStyle(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
return DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
HeaderStyleProperty,
row.DataGridOwner,
DataGrid.RowHeaderStyleProperty);
}
private static object OnCoerceHeaderTemplate(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
return DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
HeaderTemplateProperty,
row.DataGridOwner,
DataGrid.RowHeaderTemplateProperty);
}
private static object OnCoerceHeaderTemplateSelector(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
return DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
HeaderTemplateSelectorProperty,
row.DataGridOwner,
DataGrid.RowHeaderTemplateSelectorProperty);
}
private static object OnCoerceBackground(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
object coercedValue = baseValue;
switch (row.AlternationIndex)
{
case 0:
coercedValue = DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
BackgroundProperty,
row.DataGridOwner,
DataGrid.RowBackgroundProperty);
break;
case 1:
coercedValue = DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
BackgroundProperty,
row.DataGridOwner,
DataGrid.AlternatingRowBackgroundProperty);
break;
}
return coercedValue;
}
private static object OnCoerceValidationErrorTemplate(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
return DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
ValidationErrorTemplateProperty,
row.DataGridOwner,
DataGrid.RowValidationErrorTemplateProperty);
}
private static object OnCoerceDetailsTemplate(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
return DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
DetailsTemplateProperty,
row.DataGridOwner,
DataGrid.RowDetailsTemplateProperty);
}
private static object OnCoerceDetailsTemplateSelector(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
return DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
DetailsTemplateSelectorProperty,
row.DataGridOwner,
DataGrid.RowDetailsTemplateSelectorProperty);
}
private static object OnCoerceDetailsVisibility(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
object visibility = DataGridHelper.GetCoercedTransferPropertyValue(
row,
baseValue,
DetailsVisibilityProperty,
row.DataGridOwner,
DataGrid.RowDetailsVisibilityModeProperty);
if (visibility is DataGridRowDetailsVisibilityMode)
{
var visibilityMode = (DataGridRowDetailsVisibilityMode)visibility;
var hasDetailsTemplate = row.DetailsTemplate != null || row.DetailsTemplateSelector != null;
var isRealItem = row.Item != CollectionView.NewItemPlaceholder;
switch (visibilityMode)
{
case DataGridRowDetailsVisibilityMode.Collapsed:
visibility = Visibility.Collapsed;
break;
case DataGridRowDetailsVisibilityMode.Visible:
visibility = hasDetailsTemplate && isRealItem ? Visibility.Visible : Visibility.Collapsed;
break;
case DataGridRowDetailsVisibilityMode.VisibleWhenSelected:
visibility = row.IsSelected && hasDetailsTemplate && isRealItem ? Visibility.Visible : Visibility.Collapsed;
break;
default:
visibility = Visibility.Collapsed;
break;
}
}
return visibility;
}
/// <summary>
/// Coerces Visibility so that the NewItemPlaceholder doesn't show up while you're entering a new Item
/// </summary>
private static object OnCoerceVisibility(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
var owningDataGrid = row.DataGridOwner;
if (row.Item == CollectionView.NewItemPlaceholder && owningDataGrid != null)
{
return owningDataGrid.PlaceholderVisibility;
}
else
{
return baseValue;
}
}
/// <summary>
/// Coerces ShouldCacheContainerSize so that the NewItemPlaceholder doesn't cache its size.
/// </summary>
private static object OnCoerceShouldCacheContainerSize(DependencyObject d, object baseValue)
{
var row = (DataGridRow)d;
if (row.Item == CollectionView.NewItemPlaceholder)
{
return false;
}
else
{
return baseValue;
}
}
#endregion
#region Notification Propagation
private static void OnNotifyRowPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
(d as DataGridRow).NotifyPropertyChanged(d, e, DataGridNotificationTarget.Rows);
}
private static void OnNotifyRowAndRowHeaderPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
(d as DataGridRow).NotifyPropertyChanged(d, e, DataGridNotificationTarget.Rows | DataGridNotificationTarget.RowHeaders);
}
private static void OnNotifyDetailsTemplatePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
DataGridRow row = (DataGridRow)d;
row.NotifyPropertyChanged(row, e, DataGridNotificationTarget.Rows | DataGridNotificationTarget.DetailsPresenter);
// It only makes sense to fire UnloadingRowDetails if the row details are already loaded. The same is true for LoadingRowDetails,
// since making row details visible will take care of firing LoadingRowDetails.
if (row.DetailsLoaded &&
d.GetValue(e.Property) == e.NewValue)
{
if (row.DataGridOwner != null)
{
row.DataGridOwner.OnUnloadingRowDetailsWrapper(row);
}
if (e.NewValue != null)
{
// Invoke LoadingRowDetails, but only after the details template is expanded (so DetailsElement will be available).
Dispatcher.CurrentDispatcher.BeginInvoke(new DispatcherOperationCallback(DataGrid.DelayedOnLoadingRowDetails), DispatcherPriority.Loaded, row);
}
}
}
private static void OnNotifyDetailsVisibilityChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var row = (DataGridRow)d;
// Notify the DataGrid at Loaded priority so the template has time to expland.
Dispatcher.CurrentDispatcher.BeginInvoke(new DispatcherOperationCallback(DelayedRowDetailsVisibilityChanged), DispatcherPriority.Loaded, row);
row.NotifyPropertyChanged(d, e, DataGridNotificationTarget.Rows | DataGridNotificationTarget.DetailsPresenter);
}
/// <summary>
/// Notifies the DataGrid that the visibility is changed. This is intended to be Invoked at lower than Layout priority to give the template time to expand.
/// </summary>
private static object DelayedRowDetailsVisibilityChanged(object arg)
{
var row = (DataGridRow)arg;
var dataGrid = row.DataGridOwner;
var detailsElement = row.DetailsPresenter != null ? row.DetailsPresenter.DetailsElement : null;
if (dataGrid != null)
{
var detailsEventArgs = new DataGridRowDetailsEventArgs(row, detailsElement);
dataGrid.OnRowDetailsVisibilityChanged(detailsEventArgs);
}
return null;
}
/// <summary>
/// Set by the CellsPresenter when it is created. Used by the Row to send down property change notifications.
/// </summary>
internal DataGridCellsPresenter CellsPresenter
{
get { return _cellsPresenter; }
set { _cellsPresenter = value; }
}
/// <summary>
/// Set by the DetailsPresenter when it is created. Used by the Row to send down property change notifications.
/// </summary>
internal DataGridDetailsPresenter DetailsPresenter
{
get { return _detailsPresenter; }
set { _detailsPresenter = value; }
}
/// <summary>
/// Set by the RowHeader when it is created. Used by the Row to send down property change notifications.
/// </summary>
internal DataGridRowHeader RowHeader
{
get { return _rowHeader; }
set { _rowHeader = value; }
}
/// <summary>
/// General notification for DependencyProperty changes from the grid or from columns.
/// </summary>
internal void NotifyPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e, DataGridNotificationTarget target)
{
NotifyPropertyChanged(d, string.Empty, e, target);
}
/// <summary>
/// General notification for DependencyProperty changes from the grid or from columns.
/// </summary>
internal void NotifyPropertyChanged(DependencyObject d, string propertyName, DependencyPropertyChangedEventArgs e, DataGridNotificationTarget target)
{
if (DataGridHelper.ShouldNotifyRows(target))
{
if (e.Property == DataGrid.RowBackgroundProperty || e.Property == DataGrid.AlternatingRowBackgroundProperty ||
e.Property == BackgroundProperty || e.Property == AlternationIndexProperty)
{
DataGridHelper.TransferProperty(this, BackgroundProperty);
}
else if (e.Property == DataGrid.RowHeaderStyleProperty || e.Property == HeaderStyleProperty)
{
DataGridHelper.TransferProperty(this, HeaderStyleProperty);
}
else if (e.Property == DataGrid.RowHeaderTemplateProperty || e.Property == HeaderTemplateProperty)
{
DataGridHelper.TransferProperty(this, HeaderTemplateProperty);
}
else if (e.Property == DataGrid.RowHeaderTemplateSelectorProperty || e.Property == HeaderTemplateSelectorProperty)
{
DataGridHelper.TransferProperty(this, HeaderTemplateSelectorProperty);
}
else if (e.Property == DataGrid.RowValidationErrorTemplateProperty || e.Property == ValidationErrorTemplateProperty)
{
DataGridHelper.TransferProperty(this, ValidationErrorTemplateProperty);
}
else if (e.Property == DataGrid.RowDetailsTemplateProperty || e.Property == DetailsTemplateProperty)
{
DataGridHelper.TransferProperty(this, DetailsTemplateProperty);
DataGridHelper.TransferProperty(this, DetailsVisibilityProperty);
}
else if (e.Property == DataGrid.RowDetailsTemplateSelectorProperty || e.Property == DetailsTemplateSelectorProperty)
{
DataGridHelper.TransferProperty(this, DetailsTemplateSelectorProperty);
DataGridHelper.TransferProperty(this, DetailsVisibilityProperty);
}
else if (e.Property == DataGrid.RowDetailsVisibilityModeProperty || e.Property == DetailsVisibilityProperty || e.Property == IsSelectedProperty)
{
DataGridHelper.TransferProperty(this, DetailsVisibilityProperty);
}
else if (e.Property == ItemProperty)
{
OnItemChanged(e.OldValue, e.NewValue);
}
else if (e.Property == HeaderProperty)
{
OnHeaderChanged(e.OldValue, e.NewValue);
}
else if (e.Property == BindingGroupProperty)
{
// Re-run validation, but wait until Binding has occured.
Dispatcher.BeginInvoke(new DispatcherOperationCallback(DelayedValidateWithoutUpdate), DispatcherPriority.DataBind, e.NewValue);
}
else if (e.Property == DataGridRow.IsEditingProperty ||
e.Property == DataGridRow.IsMouseOverProperty ||
e.Property == DataGrid.IsKeyboardFocusWithinProperty)
{
UpdateVisualState();
}
}
if (DataGridHelper.ShouldNotifyDetailsPresenter(target))
{
if (DetailsPresenter != null)
{
DetailsPresenter.NotifyPropertyChanged(d, e);
}
}
if (DataGridHelper.ShouldNotifyCellsPresenter(target) ||
DataGridHelper.ShouldNotifyCells(target) ||
DataGridHelper.ShouldRefreshCellContent(target))
{
DataGridCellsPresenter cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
cellsPresenter.NotifyPropertyChanged(d, propertyName, e, target);
}
}
if (DataGridHelper.ShouldNotifyRowHeaders(target) && RowHeader != null)
{
RowHeader.NotifyPropertyChanged(d, e);
}
}
private object DelayedValidateWithoutUpdate(object arg)
{
// Only validate if we have an Item.
var bindingGroup = (BindingGroup)arg;
if (bindingGroup != null && bindingGroup.Items.Count > 0)
{
bindingGroup.ValidateWithoutUpdate();
}
return null;
}
/// <summary>
/// Fired when the Row is attached to the DataGrid. The scenario here is if the user is scrolling and
/// the Row is a recycled container that was just added back to the visual tree. Properties that rely on a value from
/// the Grid should be reevaluated because they may be stale.
/// </summary>
/// <remarks>
/// Properties can obviously be stale if the DataGrid's value changes while the row is disconnected. They can also
/// be stale for unobvious reasons.
///
/// For example, the Style property is invalidated when we detect a new Visual parent. This happens for
/// elements in the row (such as the RowHeader) before Prepare is called on the Row. The coercion callback
/// will thus be unable to find the DataGrid and will return the wrong value.
///
/// There is a potential for perf work here. If we know a DP isn't invalidated when the visual tree is reconnected
/// and we know that the Grid hasn't modified that property then its value is likely fine. We could also cache whether
/// or not the Grid's property is the one that's winning. If not, no need to redo the coercion. This notification
/// is pretty fast already and thus not worth the work for now.
/// </remarks>
private void SyncProperties(bool forcePrepareCells)
{
// Coerce all properties on Row that depend on values from the DataGrid
// Style is ok since it's equivalent to ItemContainerStyle and has already been invalidated.
DataGridHelper.TransferProperty(this, BackgroundProperty);
DataGridHelper.TransferProperty(this, HeaderStyleProperty);
DataGridHelper.TransferProperty(this, HeaderTemplateProperty);
DataGridHelper.TransferProperty(this, HeaderTemplateSelectorProperty);
DataGridHelper.TransferProperty(this, ValidationErrorTemplateProperty);
DataGridHelper.TransferProperty(this, DetailsTemplateProperty);
DataGridHelper.TransferProperty(this, DetailsTemplateSelectorProperty);
DataGridHelper.TransferProperty(this, DetailsVisibilityProperty);
CoerceValue(VisibilityProperty); // Handle NewItemPlaceholder case
RestoreAttachedItemValue(this, DetailsVisibilityProperty);
var cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
cellsPresenter.SyncProperties(forcePrepareCells);
RestoreAttachedItemValue(cellsPresenter, DataGridCellsPresenter.HeightProperty);
}
if (DetailsPresenter != null)
{
DetailsPresenter.SyncProperties();
}
if (RowHeader != null)
{
RowHeader.SyncProperties();
}
}
#endregion
#region Alternation
/// <summary>
/// AlternationIndex is set on containers generated for an ItemsControl, when
/// the ItemsControl's AlternationCount property is positive. The AlternationIndex
/// lies in the range [0, AlternationCount), and adjacent containers always get
/// assigned different values.
/// </summary>
/// <remarks>
/// Exposes ItemsControl.AlternationIndexProperty attached property as a direct property.
/// </remarks>
public int AlternationIndex
{
get { return (int)GetValue(AlternationIndexProperty); }
}
/// <summary>
/// DependencyProperty for AlternationIndex.
/// </summary>
/// <remarks>
/// Same as ItemsControl.AlternationIndexProperty.
/// </remarks>
public static readonly DependencyProperty AlternationIndexProperty = ItemsControl.AlternationIndexProperty.AddOwner(typeof(DataGridRow));
#endregion
#region Selection
/// <summary>
/// Indicates whether this DataGridRow is selected.
/// </summary>
/// <remarks>
/// When IsSelected is set to true, an InvalidOperationException may be
/// thrown if the value of the SelectionUnit property on the parent DataGrid
/// prevents selection or rows.
/// </remarks>
[Bindable(true), Category("Appearance")]
public bool IsSelected
{
get { return (bool)GetValue(IsSelectedProperty); }
set { SetValue(IsSelectedProperty, value); }
}
/// <summary>
/// The DependencyProperty for the IsSelected property.
/// </summary>
public static readonly DependencyProperty IsSelectedProperty = Selector.IsSelectedProperty.AddOwner(
typeof(DataGridRow),
new FrameworkPropertyMetadata(false, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault | FrameworkPropertyMetadataOptions.Journal, new PropertyChangedCallback(OnIsSelectedChanged)));
private static void OnIsSelectedChanged(object sender, DependencyPropertyChangedEventArgs e)
{
DataGridRow row = (DataGridRow)sender;
bool isSelected = (bool)e.NewValue;
if (isSelected && !row.IsSelectable)
{
throw new InvalidOperationException(SR.DataGridRow_CannotSelectRowWhenCells);
}
DataGrid grid = row.DataGridOwner;
if (grid != null && row.DataContext != null)
{
DataGridAutomationPeer gridPeer = UIElementAutomationPeer.FromElement(grid) as DataGridAutomationPeer;
if (gridPeer != null)
{
DataGridItemAutomationPeer rowItemPeer = gridPeer.FindOrCreateItemAutomationPeer(row.DataContext) as DataGridItemAutomationPeer;
if (rowItemPeer != null)
{
rowItemPeer.RaisePropertyChangedEvent(
System.Windows.Automation.SelectionItemPatternIdentifiers.IsSelectedProperty,
(bool)e.OldValue,
isSelected);
}
}
}
// Update the header's IsRowSelected property
row.NotifyPropertyChanged(row, e, DataGridNotificationTarget.Rows | DataGridNotificationTarget.RowHeaders);
// This will raise the appropriate selection event, which will
// bubble to the DataGrid. The base class Selector code will listen
// for these events and will update SelectedItems as necessary.
row.RaiseSelectionChangedEvent(isSelected);
row.UpdateVisualState();
// Update the header's IsRowSelected property
row.NotifyPropertyChanged(row, e, DataGridNotificationTarget.Rows | DataGridNotificationTarget.RowHeaders);
}
private void RaiseSelectionChangedEvent(bool isSelected)
{
if (isSelected)
{
OnSelected(new RoutedEventArgs(SelectedEvent, this));
}
else
{
OnUnselected(new RoutedEventArgs(UnselectedEvent, this));
}
}
/// <summary>
/// Raised when the item's IsSelected property becomes true.
/// </summary>
public static readonly RoutedEvent SelectedEvent = Selector.SelectedEvent.AddOwner(typeof(DataGridRow));
/// <summary>
/// Raised when the item's IsSelected property becomes true.
/// </summary>
public event RoutedEventHandler Selected
{
add
{
AddHandler(SelectedEvent, value);
}
remove
{
RemoveHandler(SelectedEvent, value);
}
}
/// <summary>
/// Called when IsSelected becomes true. Raises the Selected event.
/// </summary>
/// <param name="e">Empty event arguments.</param>
protected virtual void OnSelected(RoutedEventArgs e)
{
RaiseEvent(e);
}
/// <summary>
/// Raised when the item's IsSelected property becomes false.
/// </summary>
public static readonly RoutedEvent UnselectedEvent = Selector.UnselectedEvent.AddOwner(typeof(DataGridRow));
/// <summary>
/// Raised when the item's IsSelected property becomes false.
/// </summary>
public event RoutedEventHandler Unselected
{
add
{
AddHandler(UnselectedEvent, value);
}
remove
{
RemoveHandler(UnselectedEvent, value);
}
}
/// <summary>
/// Called when IsSelected becomes false. Raises the Unselected event.
/// </summary>
/// <param name="e">Empty event arguments.</param>
protected virtual void OnUnselected(RoutedEventArgs e)
{
RaiseEvent(e);
}
/// <summary>
/// Determines if a row can be selected, based on the DataGrid's SelectionUnit property.
/// </summary>
private bool IsSelectable
{
get
{
DataGrid dataGrid = DataGridOwner;
if (dataGrid != null)
{
DataGridSelectionUnit unit = dataGrid.SelectionUnit;
return (unit == DataGridSelectionUnit.FullRow) ||
(unit == DataGridSelectionUnit.CellOrRowHeader);
}
return true;
}
}
#endregion
#region Editing
/// <summary>
/// Whether the row is in editing mode.
/// </summary>
public bool IsEditing
{
get { return (bool)GetValue(IsEditingProperty); }
internal set { SetValue(IsEditingPropertyKey, value); }
}
private static readonly DependencyPropertyKey IsEditingPropertyKey =
DependencyProperty.RegisterReadOnly("IsEditing", typeof(bool), typeof(DataGridRow), new FrameworkPropertyMetadata(false, OnNotifyRowAndRowHeaderPropertyChanged));
/// <summary>
/// The DependencyProperty for IsEditing.
/// </summary>
public static readonly DependencyProperty IsEditingProperty = IsEditingPropertyKey.DependencyProperty;
#endregion
#region Automation
protected override System.Windows.Automation.Peers.AutomationPeer OnCreateAutomationPeer()
{
return new System.Windows.Automation.Peers.DataGridRowAutomationPeer(this);
}
#endregion
#region Column Virtualization
/// <summary>
/// Method which tries to scroll a cell for given index into the scroll view
/// </summary>
/// <param name="index"></param>
internal void ScrollCellIntoView(int index)
{
DataGridCellsPresenter cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
cellsPresenter.ScrollCellIntoView(index);
}
}
#endregion
#region Layout
/// <summary>
/// Arrange
/// </summary>
protected override Size ArrangeOverride(Size arrangeBounds)
{
DataGrid dataGrid = DataGridOwner;
if (dataGrid != null)
{
dataGrid.QueueInvalidateCellsPanelHorizontalOffset();
}
return base.ArrangeOverride(arrangeBounds);
}
#endregion
#region New Item
/// <summary>
/// Indicates whether the row belongs to new item (both placeholder
/// as well as adding item) or not.
/// </summary>
public bool IsNewItem
{
get { return (bool)GetValue(IsNewItemProperty); }
internal set { SetValue(IsNewItemPropertyKey, value); }
}
/// <summary>
/// Using a DependencyProperty as the backing store for IsNewItem. This enables animation, styling, binding, etc...
/// </summary>
internal static readonly DependencyPropertyKey IsNewItemPropertyKey =
DependencyProperty.RegisterReadOnly("IsNewItem", typeof(bool), typeof(DataGridRow), new FrameworkPropertyMetadata(false));
/// <summary>
/// DependencyProperty for IsNewItem property.
/// </summary>
public static readonly DependencyProperty IsNewItemProperty =
IsNewItemPropertyKey.DependencyProperty;
#endregion
#region Helpers
/// <summary>
/// Returns the index of this row within the DataGrid's list of item containers.
/// </summary>
/// <remarks>
/// This method performs a linear search.
/// </remarks>
/// <returns>The index, if found, -1 otherwise.</returns>
public int GetIndex()
{
DataGrid dataGridOwner = DataGridOwner;
if (dataGridOwner != null)
{
return dataGridOwner.ItemContainerGenerator.IndexFromContainer(this);
}
return -1;
}
/// <summary>
/// Searchs up the visual parent chain from the given element until
/// a DataGridRow element is found.
/// </summary>
/// <param name="element">The descendent of a DataGridRow.</param>
/// <returns>
/// The first ancestor DataGridRow of the element parameter.
/// Returns null of none is found.
/// </returns>
public static DataGridRow GetRowContainingElement(FrameworkElement element)
{
return DataGridHelper.FindVisualParent<DataGridRow>(element);
}
internal DataGrid DataGridOwner
{
get { return _owner; }
}
/// <summary>
/// Returns true if the DetailsPresenter is supposed to draw gridlines for the row. Only true
/// if the DetailsPresenter hooked itself up properly to the Row.
/// </summary>
internal bool DetailsPresenterDrawsGridLines
{
get { return _detailsPresenter != null && _detailsPresenter.Visibility == Visibility.Visible; }
}
/// <summary>
/// Acceses the CellsPresenter and attempts to get the cell at the given index.
/// This is not necessarily the display order.
/// </summary>
internal DataGridCell TryGetCell(int index)
{
DataGridCellsPresenter cellsPresenter = CellsPresenter;
if (cellsPresenter != null)
{
return cellsPresenter.ItemContainerGenerator.ContainerFromIndex(index) as DataGridCell;
}
return null;
}
#endregion
#region Data
// Tracks whether row details have been displayed.
// true - row details template has been loaded and has rendered at least once
// false - row details template has either is unset, or has never been asked to render
internal bool _detailsLoaded;
private DataGrid _owner;
private DataGridCellsPresenter _cellsPresenter;
private DataGridDetailsPresenter _detailsPresenter;
private DataGridRowHeader _rowHeader;
private ContainerTracking<DataGridRow> _tracker;
private double _cellsPresenterResizeHeight;
#endregion
}
}
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