Code:
/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Framework / System / Windows / Controls / DataGridHelper.cs / 1305600 / DataGridHelper.cs
//----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//---------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Threading;
using MS.Internal;
namespace System.Windows.Controls
{
///
/// Helper code for DataGrid.
///
internal static class DataGridHelper
{
#region GridLines
// Common code for drawing GridLines. Shared by DataGridDetailsPresenter, DataGridCellsPresenter, and Cell
///
/// Returns a size based on the given one with the given double subtracted out from the Width or Height.
/// Used to adjust for the thickness of grid lines.
///
public static Size SubtractFromSize(Size size, double thickness, bool height)
{
if (height)
{
return new Size(size.Width, Math.Max(0.0, size.Height - thickness));
}
else
{
return new Size(Math.Max(0.0, size.Width - thickness), size.Height);
}
}
///
/// Test if either the vertical or horizontal gridlines are visible.
///
public static bool IsGridLineVisible(DataGrid dataGrid, bool isHorizontal)
{
if (dataGrid != null)
{
DataGridGridLinesVisibility visibility = dataGrid.GridLinesVisibility;
switch (visibility)
{
case DataGridGridLinesVisibility.All:
return true;
case DataGridGridLinesVisibility.Horizontal:
return isHorizontal;
case DataGridGridLinesVisibility.None:
return false;
case DataGridGridLinesVisibility.Vertical:
return !isHorizontal;
}
}
return false;
}
#endregion
#region Notification Propagation
public static bool ShouldNotifyCells(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.Cells);
}
public static bool ShouldNotifyCellsPresenter(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.CellsPresenter);
}
public static bool ShouldNotifyColumns(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.Columns);
}
public static bool ShouldNotifyColumnHeaders(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.ColumnHeaders);
}
public static bool ShouldNotifyColumnHeadersPresenter(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.ColumnHeadersPresenter);
}
public static bool ShouldNotifyColumnCollection(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.ColumnCollection);
}
public static bool ShouldNotifyDataGrid(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.DataGrid);
}
public static bool ShouldNotifyDetailsPresenter(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.DetailsPresenter);
}
public static bool ShouldRefreshCellContent(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.RefreshCellContent);
}
public static bool ShouldNotifyRowHeaders(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.RowHeaders);
}
public static bool ShouldNotifyRows(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.Rows);
}
public static bool ShouldNotifyRowSubtree(DataGridNotificationTarget target)
{
DataGridNotificationTarget value =
DataGridNotificationTarget.Rows |
DataGridNotificationTarget.RowHeaders |
DataGridNotificationTarget.CellsPresenter |
DataGridNotificationTarget.Cells |
DataGridNotificationTarget.RefreshCellContent |
DataGridNotificationTarget.DetailsPresenter;
return TestTarget(target, value);
}
private static bool TestTarget(DataGridNotificationTarget target, DataGridNotificationTarget value)
{
return (target & value) != 0;
}
#endregion
#region Tree Helpers
///
/// Walks up the templated parent tree looking for a parent type.
///
public static T FindParent(FrameworkElement element) where T : FrameworkElement
{
FrameworkElement parent = element.TemplatedParent as FrameworkElement;
while (parent != null)
{
T correctlyTyped = parent as T;
if (correctlyTyped != null)
{
return correctlyTyped;
}
parent = parent.TemplatedParent as FrameworkElement;
}
return null;
}
public static T FindVisualParent(UIElement element) where T : UIElement
{
UIElement parent = element;
while (parent != null)
{
T correctlyTyped = parent as T;
if (correctlyTyped != null)
{
return correctlyTyped;
}
parent = VisualTreeHelper.GetParent(parent) as UIElement;
}
return null;
}
///
/// Helper method which determines if any of the elements of
/// the tree is focusable and has tab stop
///
public static bool TreeHasFocusAndTabStop(DependencyObject element)
{
if (element == null)
{
return false;
}
UIElement uielement = element as UIElement;
if (uielement != null)
{
if (uielement.Focusable && KeyboardNavigation.GetIsTabStop(uielement))
{
return true;
}
}
else
{
ContentElement contentElement = element as ContentElement;
if (contentElement != null && contentElement.Focusable && KeyboardNavigation.GetIsTabStop(contentElement))
{
return true;
}
}
int childCount = VisualTreeHelper.GetChildrenCount(element);
for (int i = 0; i < childCount; i++)
{
DependencyObject child = VisualTreeHelper.GetChild(element, i) as DependencyObject;
if (TreeHasFocusAndTabStop(child))
{
return true;
}
}
return false;
}
#endregion
#region Cells Panel Helper
///
/// Invalidates a cell's panel if its column's width changes sufficiently.
///
/// The cell or header.
///
public static void OnColumnWidthChanged(IProvideDataGridColumn cell, DependencyPropertyChangedEventArgs e)
{
Debug.Assert((cell is DataGridCell) || (cell is DataGridColumnHeader), "provideColumn should be one of the cell or header containers.");
UIElement element = (UIElement)cell;
DataGridColumn column = cell.Column;
bool isColumnHeader = (cell is DataGridColumnHeader);
if (column != null)
{
// determine the desired value of width for auto kind columns
DataGridLength width = column.Width;
if (width.IsAuto ||
(!isColumnHeader && width.IsSizeToCells) ||
(isColumnHeader && width.IsSizeToHeader))
{
DataGridLength oldWidth = (DataGridLength)e.OldValue;
double desiredWidth = 0.0;
if (oldWidth.UnitType != width.UnitType)
{
double constraintWidth = column.GetConstraintWidth(isColumnHeader);
if (!DoubleUtil.AreClose(element.DesiredSize.Width, constraintWidth))
{
element.InvalidateMeasure();
element.Measure(new Size(constraintWidth, double.PositiveInfinity));
}
desiredWidth = element.DesiredSize.Width;
}
else
{
desiredWidth = oldWidth.DesiredValue;
}
if (DoubleUtil.IsNaN(width.DesiredValue) ||
DoubleUtil.LessThan(width.DesiredValue, desiredWidth))
{
column.SetWidthInternal(new DataGridLength(width.Value, width.UnitType, desiredWidth, width.DisplayValue));
}
}
}
}
///
/// Helper method which returns the clip for the cell based on whether it overlaps with frozen columns or not
///
/// The cell or header.
///
/// Helper method which returns the parent DataGridCellsPanel for a cell
///
/// The cell or header.
/// Parent panel of the given cell or header
public static DataGridCellsPanel GetParentPanelForCell(IProvideDataGridColumn cell)
{
Debug.Assert((cell is DataGridCell) || (cell is DataGridColumnHeader), "provideColumn should be one of the cell or header containers.");
UIElement element = (UIElement)cell;
return VisualTreeHelper.GetParent(element) as DataGridCellsPanel;
}
///
/// Helper method which returns the parent DataGridCellPanel's offset from the scroll viewer
/// for a cell or Header
///
/// The cell or header.
/// Parent Panel's offset with respect to scroll viewer
public static double GetParentCellsPanelHorizontalOffset(IProvideDataGridColumn cell)
{
DataGridCellsPanel panel = GetParentPanelForCell(cell);
if (panel != null)
{
return panel.ComputeCellsPanelHorizontalOffset();
}
return 0.0;
}
#endregion
#region Property Helpers
public static bool IsDefaultValue(DependencyObject d, DependencyProperty dp)
{
return DependencyPropertyHelper.GetValueSource(d, dp).BaseValueSource == BaseValueSource.Default;
}
public static object GetCoercedTransferPropertyValue(
DependencyObject baseObject,
object baseValue,
DependencyProperty baseProperty,
DependencyObject parentObject,
DependencyProperty parentProperty)
{
return GetCoercedTransferPropertyValue(
baseObject,
baseValue,
baseProperty,
parentObject,
parentProperty,
null,
null);
}
///
/// Computes the value of a given property based on the DataGrid property transfer rules.
///
///
/// This is intended to be called from within the coercion of the baseProperty.
///
/// The target object which recieves the transferred property
/// The baseValue that was passed into the coercion delegate
/// The property that is being coerced
/// The object that contains the parentProperty
/// A property who's value should be transfered (via coercion) to the baseObject if it has a higher precedence.
/// Same as parentObject but evaluated at a lower presedece for a given BaseValueSource
/// Same as parentProperty but evaluated at a lower presedece for a given BaseValueSource
///
/// Causes the given DependencyProperty to be coerced in transfer mode.
///
///
/// This should be called from within the target object's NotifyPropertyChanged. It MUST be called in
/// response to a change in the target property.
///
/// The DependencyObject which contains the property that needs to be transfered.
/// The DependencyProperty that is the target of the property transfer.
public static void TransferProperty(DependencyObject d, DependencyProperty p)
{
var transferEnabledMap = GetPropertyTransferEnabledMapForObject(d);
transferEnabledMap[p] = true;
d.CoerceValue(p);
transferEnabledMap[p] = false;
}
private static Dictionary GetPropertyTransferEnabledMapForObject(DependencyObject d)
{
Dictionary propertyTransferEnabledForObject;
if (!_propertyTransferEnabledMap.TryGetValue(d, out propertyTransferEnabledForObject))
{
propertyTransferEnabledForObject = new Dictionary();
_propertyTransferEnabledMap.Add(d, propertyTransferEnabledForObject);
}
return propertyTransferEnabledForObject;
}
internal static bool IsPropertyTransferEnabled(DependencyObject d, DependencyProperty p)
{
Dictionary propertyTransferEnabledForObject;
if ( _propertyTransferEnabledMap.TryGetValue(d, out propertyTransferEnabledForObject))
{
bool isPropertyTransferEnabled;
if (propertyTransferEnabledForObject.TryGetValue(p, out isPropertyTransferEnabled))
{
return isPropertyTransferEnabled;
}
}
return false;
}
///
/// Tracks which properties are currently being transfered. This information is needed when GetPropertyTransferEnabledMapForObject
/// is called inside of Coercion.
///
private static ConditionalWeakTable> _propertyTransferEnabledMap = new ConditionalWeakTable>();
#endregion
#region Binding
///
/// Returns true if the binding (or any part of it) is OneWay.
///
internal static bool IsOneWay(BindingBase bindingBase)
{
if (bindingBase == null)
{
return false;
}
// If it is a standard Binding, then check if it's Mode is OneWay
Binding binding = bindingBase as Binding;
if (binding != null)
{
return binding.Mode == BindingMode.OneWay;
}
// A multi-binding can be OneWay as well
MultiBinding multiBinding = bindingBase as MultiBinding;
if (multiBinding != null)
{
return multiBinding.Mode == BindingMode.OneWay;
}
// A priority binding is a list of bindings, if any are OneWay, we'll call it OneWay
PriorityBinding priBinding = bindingBase as PriorityBinding;
if (priBinding != null)
{
Collection subBindings = priBinding.Bindings;
int count = subBindings.Count;
for (int i = 0; i < count; i++)
{
if (IsOneWay(subBindings[i]))
{
return true;
}
}
}
return false;
}
internal static BindingExpression GetBindingExpression(FrameworkElement element, DependencyProperty dp)
{
if (element != null)
{
return element.GetBindingExpression(dp);
}
return null;
}
internal static bool ValidateWithoutUpdate(FrameworkElement element)
{
bool result = true;
BindingGroup bindingGroup = element.BindingGroup;
DataGridCell cell = (element != null) ? element.Parent as DataGridCell : null;
if (bindingGroup != null && cell != null)
{
Collection expressions = bindingGroup.BindingExpressions;
for (int i=expressions.Count-1; i>=0; --i)
{
BindingExpressionBase beb = expressions[i];
if (VisualTreeHelper.IsAncestorOf(cell, beb.TargetElement, typeof(DataGridCell)))
{
result = beb.ValidateWithoutUpdate() && result;
}
}
}
return result;
}
internal static void UpdateTarget(FrameworkElement element)
{
BindingGroup bindingGroup = element.BindingGroup;
DataGridCell cell = (element != null) ? element.Parent as DataGridCell : null;
if (bindingGroup != null && cell != null)
{
Collection expressions = bindingGroup.BindingExpressions;
for (int i=expressions.Count-1; i>=0; --i)
{
BindingExpressionBase beb = expressions[i];
if (VisualTreeHelper.IsAncestorOf(cell, beb.TargetElement, typeof(DataGridCell)))
{
beb.UpdateTarget();
}
}
}
}
internal static void SyncColumnProperty(DependencyObject column, DependencyObject content, DependencyProperty contentProperty, DependencyProperty columnProperty)
{
if (IsDefaultValue(column, columnProperty))
{
content.ClearValue(contentProperty);
}
else
{
content.SetValue(contentProperty, column.GetValue(columnProperty));
}
}
internal static string GetPathFromBinding(Binding binding)
{
if (binding != null)
{
if (!string.IsNullOrEmpty(binding.XPath))
{
return binding.XPath;
}
else if (binding.Path != null)
{
return binding.Path.Path;
}
}
return null;
}
#endregion
#region Other Helpers
///
/// Method which takes in DataGridHeadersVisibility parameter
/// and determines if row headers are visible.
///
public static bool AreRowHeadersVisible(DataGridHeadersVisibility headersVisibility)
{
return (headersVisibility & DataGridHeadersVisibility.Row) == DataGridHeadersVisibility.Row;
}
///
/// Helper method which coerces a value such that it satisfies min and max restrictions
///
public static double CoerceToMinMax(double value, double minValue, double maxValue)
{
value = Math.Max(value, minValue);
value = Math.Min(value, maxValue);
return value;
}
///
/// Helper to check if TextCompositionEventArgs.Text has any non
/// escape characters.
///
public static bool HasNonEscapeCharacters(TextCompositionEventArgs textArgs)
{
if (textArgs != null)
{
string text = textArgs.Text;
for (int i = 0, count = text.Length; i < count; i++)
{
if (text[i] != _escapeChar)
{
return true;
}
}
}
return false;
}
private const char _escapeChar = '\u001b';
#endregion
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
//----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//---------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Threading;
using MS.Internal;
namespace System.Windows.Controls
{
///
/// Helper code for DataGrid.
///
internal static class DataGridHelper
{
#region GridLines
// Common code for drawing GridLines. Shared by DataGridDetailsPresenter, DataGridCellsPresenter, and Cell
///
/// Returns a size based on the given one with the given double subtracted out from the Width or Height.
/// Used to adjust for the thickness of grid lines.
///
public static Size SubtractFromSize(Size size, double thickness, bool height)
{
if (height)
{
return new Size(size.Width, Math.Max(0.0, size.Height - thickness));
}
else
{
return new Size(Math.Max(0.0, size.Width - thickness), size.Height);
}
}
///
/// Test if either the vertical or horizontal gridlines are visible.
///
public static bool IsGridLineVisible(DataGrid dataGrid, bool isHorizontal)
{
if (dataGrid != null)
{
DataGridGridLinesVisibility visibility = dataGrid.GridLinesVisibility;
switch (visibility)
{
case DataGridGridLinesVisibility.All:
return true;
case DataGridGridLinesVisibility.Horizontal:
return isHorizontal;
case DataGridGridLinesVisibility.None:
return false;
case DataGridGridLinesVisibility.Vertical:
return !isHorizontal;
}
}
return false;
}
#endregion
#region Notification Propagation
public static bool ShouldNotifyCells(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.Cells);
}
public static bool ShouldNotifyCellsPresenter(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.CellsPresenter);
}
public static bool ShouldNotifyColumns(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.Columns);
}
public static bool ShouldNotifyColumnHeaders(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.ColumnHeaders);
}
public static bool ShouldNotifyColumnHeadersPresenter(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.ColumnHeadersPresenter);
}
public static bool ShouldNotifyColumnCollection(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.ColumnCollection);
}
public static bool ShouldNotifyDataGrid(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.DataGrid);
}
public static bool ShouldNotifyDetailsPresenter(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.DetailsPresenter);
}
public static bool ShouldRefreshCellContent(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.RefreshCellContent);
}
public static bool ShouldNotifyRowHeaders(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.RowHeaders);
}
public static bool ShouldNotifyRows(DataGridNotificationTarget target)
{
return TestTarget(target, DataGridNotificationTarget.Rows);
}
public static bool ShouldNotifyRowSubtree(DataGridNotificationTarget target)
{
DataGridNotificationTarget value =
DataGridNotificationTarget.Rows |
DataGridNotificationTarget.RowHeaders |
DataGridNotificationTarget.CellsPresenter |
DataGridNotificationTarget.Cells |
DataGridNotificationTarget.RefreshCellContent |
DataGridNotificationTarget.DetailsPresenter;
return TestTarget(target, value);
}
private static bool TestTarget(DataGridNotificationTarget target, DataGridNotificationTarget value)
{
return (target & value) != 0;
}
#endregion
#region Tree Helpers
///
/// Walks up the templated parent tree looking for a parent type.
///
public static T FindParent(FrameworkElement element) where T : FrameworkElement
{
FrameworkElement parent = element.TemplatedParent as FrameworkElement;
while (parent != null)
{
T correctlyTyped = parent as T;
if (correctlyTyped != null)
{
return correctlyTyped;
}
parent = parent.TemplatedParent as FrameworkElement;
}
return null;
}
public static T FindVisualParent(UIElement element) where T : UIElement
{
UIElement parent = element;
while (parent != null)
{
T correctlyTyped = parent as T;
if (correctlyTyped != null)
{
return correctlyTyped;
}
parent = VisualTreeHelper.GetParent(parent) as UIElement;
}
return null;
}
///
/// Helper method which determines if any of the elements of
/// the tree is focusable and has tab stop
///
public static bool TreeHasFocusAndTabStop(DependencyObject element)
{
if (element == null)
{
return false;
}
UIElement uielement = element as UIElement;
if (uielement != null)
{
if (uielement.Focusable && KeyboardNavigation.GetIsTabStop(uielement))
{
return true;
}
}
else
{
ContentElement contentElement = element as ContentElement;
if (contentElement != null && contentElement.Focusable && KeyboardNavigation.GetIsTabStop(contentElement))
{
return true;
}
}
int childCount = VisualTreeHelper.GetChildrenCount(element);
for (int i = 0; i < childCount; i++)
{
DependencyObject child = VisualTreeHelper.GetChild(element, i) as DependencyObject;
if (TreeHasFocusAndTabStop(child))
{
return true;
}
}
return false;
}
#endregion
#region Cells Panel Helper
///
/// Invalidates a cell's panel if its column's width changes sufficiently.
///
/// The cell or header.
///
public static void OnColumnWidthChanged(IProvideDataGridColumn cell, DependencyPropertyChangedEventArgs e)
{
Debug.Assert((cell is DataGridCell) || (cell is DataGridColumnHeader), "provideColumn should be one of the cell or header containers.");
UIElement element = (UIElement)cell;
DataGridColumn column = cell.Column;
bool isColumnHeader = (cell is DataGridColumnHeader);
if (column != null)
{
// determine the desired value of width for auto kind columns
DataGridLength width = column.Width;
if (width.IsAuto ||
(!isColumnHeader && width.IsSizeToCells) ||
(isColumnHeader && width.IsSizeToHeader))
{
DataGridLength oldWidth = (DataGridLength)e.OldValue;
double desiredWidth = 0.0;
if (oldWidth.UnitType != width.UnitType)
{
double constraintWidth = column.GetConstraintWidth(isColumnHeader);
if (!DoubleUtil.AreClose(element.DesiredSize.Width, constraintWidth))
{
element.InvalidateMeasure();
element.Measure(new Size(constraintWidth, double.PositiveInfinity));
}
desiredWidth = element.DesiredSize.Width;
}
else
{
desiredWidth = oldWidth.DesiredValue;
}
if (DoubleUtil.IsNaN(width.DesiredValue) ||
DoubleUtil.LessThan(width.DesiredValue, desiredWidth))
{
column.SetWidthInternal(new DataGridLength(width.Value, width.UnitType, desiredWidth, width.DisplayValue));
}
}
}
}
///
/// Helper method which returns the clip for the cell based on whether it overlaps with frozen columns or not
///
/// The cell or header.
///
/// Helper method which returns the parent DataGridCellsPanel for a cell
///
/// The cell or header.
/// Parent panel of the given cell or header
public static DataGridCellsPanel GetParentPanelForCell(IProvideDataGridColumn cell)
{
Debug.Assert((cell is DataGridCell) || (cell is DataGridColumnHeader), "provideColumn should be one of the cell or header containers.");
UIElement element = (UIElement)cell;
return VisualTreeHelper.GetParent(element) as DataGridCellsPanel;
}
///
/// Helper method which returns the parent DataGridCellPanel's offset from the scroll viewer
/// for a cell or Header
///
/// The cell or header.
/// Parent Panel's offset with respect to scroll viewer
public static double GetParentCellsPanelHorizontalOffset(IProvideDataGridColumn cell)
{
DataGridCellsPanel panel = GetParentPanelForCell(cell);
if (panel != null)
{
return panel.ComputeCellsPanelHorizontalOffset();
}
return 0.0;
}
#endregion
#region Property Helpers
public static bool IsDefaultValue(DependencyObject d, DependencyProperty dp)
{
return DependencyPropertyHelper.GetValueSource(d, dp).BaseValueSource == BaseValueSource.Default;
}
public static object GetCoercedTransferPropertyValue(
DependencyObject baseObject,
object baseValue,
DependencyProperty baseProperty,
DependencyObject parentObject,
DependencyProperty parentProperty)
{
return GetCoercedTransferPropertyValue(
baseObject,
baseValue,
baseProperty,
parentObject,
parentProperty,
null,
null);
}
///
/// Computes the value of a given property based on the DataGrid property transfer rules.
///
///
/// This is intended to be called from within the coercion of the baseProperty.
///
/// The target object which recieves the transferred property
/// The baseValue that was passed into the coercion delegate
/// The property that is being coerced
/// The object that contains the parentProperty
/// A property who's value should be transfered (via coercion) to the baseObject if it has a higher precedence.
/// Same as parentObject but evaluated at a lower presedece for a given BaseValueSource
/// Same as parentProperty but evaluated at a lower presedece for a given BaseValueSource
///
/// Causes the given DependencyProperty to be coerced in transfer mode.
///
///
/// This should be called from within the target object's NotifyPropertyChanged. It MUST be called in
/// response to a change in the target property.
///
/// The DependencyObject which contains the property that needs to be transfered.
/// The DependencyProperty that is the target of the property transfer.
public static void TransferProperty(DependencyObject d, DependencyProperty p)
{
var transferEnabledMap = GetPropertyTransferEnabledMapForObject(d);
transferEnabledMap[p] = true;
d.CoerceValue(p);
transferEnabledMap[p] = false;
}
private static Dictionary GetPropertyTransferEnabledMapForObject(DependencyObject d)
{
Dictionary propertyTransferEnabledForObject;
if (!_propertyTransferEnabledMap.TryGetValue(d, out propertyTransferEnabledForObject))
{
propertyTransferEnabledForObject = new Dictionary();
_propertyTransferEnabledMap.Add(d, propertyTransferEnabledForObject);
}
return propertyTransferEnabledForObject;
}
internal static bool IsPropertyTransferEnabled(DependencyObject d, DependencyProperty p)
{
Dictionary propertyTransferEnabledForObject;
if ( _propertyTransferEnabledMap.TryGetValue(d, out propertyTransferEnabledForObject))
{
bool isPropertyTransferEnabled;
if (propertyTransferEnabledForObject.TryGetValue(p, out isPropertyTransferEnabled))
{
return isPropertyTransferEnabled;
}
}
return false;
}
///
/// Tracks which properties are currently being transfered. This information is needed when GetPropertyTransferEnabledMapForObject
/// is called inside of Coercion.
///
private static ConditionalWeakTable> _propertyTransferEnabledMap = new ConditionalWeakTable>();
#endregion
#region Binding
///
/// Returns true if the binding (or any part of it) is OneWay.
///
internal static bool IsOneWay(BindingBase bindingBase)
{
if (bindingBase == null)
{
return false;
}
// If it is a standard Binding, then check if it's Mode is OneWay
Binding binding = bindingBase as Binding;
if (binding != null)
{
return binding.Mode == BindingMode.OneWay;
}
// A multi-binding can be OneWay as well
MultiBinding multiBinding = bindingBase as MultiBinding;
if (multiBinding != null)
{
return multiBinding.Mode == BindingMode.OneWay;
}
// A priority binding is a list of bindings, if any are OneWay, we'll call it OneWay
PriorityBinding priBinding = bindingBase as PriorityBinding;
if (priBinding != null)
{
Collection subBindings = priBinding.Bindings;
int count = subBindings.Count;
for (int i = 0; i < count; i++)
{
if (IsOneWay(subBindings[i]))
{
return true;
}
}
}
return false;
}
internal static BindingExpression GetBindingExpression(FrameworkElement element, DependencyProperty dp)
{
if (element != null)
{
return element.GetBindingExpression(dp);
}
return null;
}
internal static bool ValidateWithoutUpdate(FrameworkElement element)
{
bool result = true;
BindingGroup bindingGroup = element.BindingGroup;
DataGridCell cell = (element != null) ? element.Parent as DataGridCell : null;
if (bindingGroup != null && cell != null)
{
Collection expressions = bindingGroup.BindingExpressions;
for (int i=expressions.Count-1; i>=0; --i)
{
BindingExpressionBase beb = expressions[i];
if (VisualTreeHelper.IsAncestorOf(cell, beb.TargetElement, typeof(DataGridCell)))
{
result = beb.ValidateWithoutUpdate() && result;
}
}
}
return result;
}
internal static void UpdateTarget(FrameworkElement element)
{
BindingGroup bindingGroup = element.BindingGroup;
DataGridCell cell = (element != null) ? element.Parent as DataGridCell : null;
if (bindingGroup != null && cell != null)
{
Collection expressions = bindingGroup.BindingExpressions;
for (int i=expressions.Count-1; i>=0; --i)
{
BindingExpressionBase beb = expressions[i];
if (VisualTreeHelper.IsAncestorOf(cell, beb.TargetElement, typeof(DataGridCell)))
{
beb.UpdateTarget();
}
}
}
}
internal static void SyncColumnProperty(DependencyObject column, DependencyObject content, DependencyProperty contentProperty, DependencyProperty columnProperty)
{
if (IsDefaultValue(column, columnProperty))
{
content.ClearValue(contentProperty);
}
else
{
content.SetValue(contentProperty, column.GetValue(columnProperty));
}
}
internal static string GetPathFromBinding(Binding binding)
{
if (binding != null)
{
if (!string.IsNullOrEmpty(binding.XPath))
{
return binding.XPath;
}
else if (binding.Path != null)
{
return binding.Path.Path;
}
}
return null;
}
#endregion
#region Other Helpers
///
/// Method which takes in DataGridHeadersVisibility parameter
/// and determines if row headers are visible.
///
public static bool AreRowHeadersVisible(DataGridHeadersVisibility headersVisibility)
{
return (headersVisibility & DataGridHeadersVisibility.Row) == DataGridHeadersVisibility.Row;
}
///
/// Helper method which coerces a value such that it satisfies min and max restrictions
///
public static double CoerceToMinMax(double value, double minValue, double maxValue)
{
value = Math.Max(value, minValue);
value = Math.Min(value, maxValue);
return value;
}
///
/// Helper to check if TextCompositionEventArgs.Text has any non
/// escape characters.
///
public static bool HasNonEscapeCharacters(TextCompositionEventArgs textArgs)
{
if (textArgs != null)
{
string text = textArgs.Text;
for (int i = 0, count = text.Length; i < count; i++)
{
if (text[i] != _escapeChar)
{
return true;
}
}
}
return false;
}
private const char _escapeChar = '\u001b';
#endregion
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
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- EventDescriptor.cs
- GacUtil.cs
- AttachedPropertyBrowsableAttribute.cs
- EncodingInfo.cs
- Int16Animation.cs
- connectionpool.cs
- HttpCachePolicyBase.cs
- RulePatternOps.cs
- BitmapEffectState.cs
- ComplexPropertyEntry.cs
- XmlSchemaFacet.cs
- BrowserDefinition.cs
- GradientBrush.cs
- UpdateTranslator.cs
- ControlAdapter.cs
- Condition.cs
- EdmToObjectNamespaceMap.cs
- DocumentReferenceCollection.cs
- ObjectParameterCollection.cs
- CopyAttributesAction.cs
- MouseEvent.cs
- TimeoutTimer.cs
- Model3DGroup.cs
- HwndTarget.cs
- SafeFileHandle.cs
- BitmapEffectrendercontext.cs
- StateManagedCollection.cs
- IgnoreSection.cs
- Win32PrintDialog.cs
- DataException.cs
- ProxyAttribute.cs
- ListViewSelectEventArgs.cs
- StringUtil.cs
- LogicalExpr.cs
- NavigationEventArgs.cs
- ContentPropertyAttribute.cs
- FileSystemInfo.cs
- XamlSerializationHelper.cs
- ErrorInfoXmlDocument.cs
- NegatedCellConstant.cs
- DriveInfo.cs
- ToolStripItem.cs
- DbParameterCollectionHelper.cs
- ExecutionContext.cs
- InstanceValue.cs
- ProxyGenerationError.cs
- XsltSettings.cs
- XPathDocument.cs
- WeakReferenceList.cs
- PriorityChain.cs
- PropertyBuilder.cs
- DbBuffer.cs
- ReliableChannelBinder.cs
- DrawingDrawingContext.cs
- GregorianCalendar.cs
- SecurityHelper.cs
- WebConfigurationHost.cs
- StylusPointProperties.cs
- ConfigurationStrings.cs
- ZoneIdentityPermission.cs
- IdnElement.cs
- Missing.cs
- RoleBoolean.cs
- InternalSafeNativeMethods.cs
- TablePatternIdentifiers.cs
- ItemContainerGenerator.cs
- PathNode.cs
- InfoCardArgumentException.cs
- ExtendedProperty.cs
- PnrpPermission.cs
- CommentEmitter.cs
- IconBitmapDecoder.cs
- Timeline.cs
- EventDescriptor.cs
- DrawingBrush.cs
- ProfileBuildProvider.cs
- TransformPattern.cs
- CopyCodeAction.cs
- SchemaInfo.cs
- BaseDataListComponentEditor.cs
- ServerIdentity.cs
- WinFormsUtils.cs
- MatchingStyle.cs
- ChannelTraceRecord.cs
- NetPeerTcpBindingElement.cs
- NetworkCredential.cs
- ItemType.cs
- NotificationContext.cs
- WinEventQueueItem.cs
- SecurityException.cs
- baseaxisquery.cs
- CompletedAsyncResult.cs
- ObjectDataSourceStatusEventArgs.cs
- AutomationFocusChangedEventArgs.cs
- Viewport3DAutomationPeer.cs
- DataRowExtensions.cs
- ObjectStateEntryBaseUpdatableDataRecord.cs
- SafeSecurityHandles.cs
- HttpListenerPrefixCollection.cs
- TextEditorSpelling.cs