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using System;
using System.Collections;
using System.ComponentModel;
using System.Windows.Threading;
using System.Windows.Data;
using System.Windows.Media;
using MS.Utility;
using MS.Internal;
using MS.Internal.Controls;
using MS.Internal.KnownBoxes;
using MS.Internal.Data;
using MS.Internal.PresentationFramework;
namespace System.Windows.Controls
{
/// <summary>
/// The base class for all controls that contain multiple items and have a header.
/// </summary>
/// <remarks>
/// HeaderedItemsControl adds Header, HeaderTemplate, and Part features to an ItemsControl.
/// </remarks>
[DefaultProperty("Header")]
[Localizability(LocalizationCategory.Menu)]
public class HeaderedItemsControl : ItemsControl
{
#region Constructors
/// <summary>
/// Default HeaderedItemsControl constructor
/// </summary>
/// <remarks>
/// Automatic determination of current Dispatcher. Use alternative constructor
/// that accepts a Dispatcher for best performance.
/// </remarks>
public HeaderedItemsControl() : base()
{
}
#endregion
#region Properties
/// <summary>
/// The DependencyProperty for the Header property.
/// Flags: None
/// Default Value: null
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HeaderProperty =
HeaderedContentControl.HeaderProperty.AddOwner(
typeof(HeaderedItemsControl),
new FrameworkPropertyMetadata(
(object) null,
new PropertyChangedCallback(OnHeaderChanged)));
/// <summary>
/// Header is the data used to for the header of each item in the control.
/// </summary>
[Bindable(true), CustomCategory("Content")]
public object Header
{
get { return GetValue(HeaderProperty); }
set { SetValue(HeaderProperty, value); }
}
/// <summary>
/// Called when HeaderProperty is invalidated on "d."
/// </summary>
private static void OnHeaderChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
HeaderedItemsControl ctrl = (HeaderedItemsControl) d;
ctrl.SetValue(HasHeaderPropertyKey, (e.NewValue != null) ? BooleanBoxes.TrueBox : BooleanBoxes.FalseBox);
ctrl.OnHeaderChanged(e.OldValue, e.NewValue);
}
/// <summary>
/// This method is invoked when the Header property changes.
/// </summary>
/// <param name="oldHeader">The old value of the Header property.</param>
/// <param name="newHeader">The new value of the Header property.</param>
protected virtual void OnHeaderChanged(object oldHeader, object newHeader)
{
// if Header should not be treated as a logical child, there's
// nothing to do
if (!IsHeaderLogical())
return;
RemoveLogicalChild(oldHeader);
AddLogicalChild(newHeader);
}
/// <summary>
/// The key needed set a read-only property.
/// </summary>
private static readonly DependencyPropertyKey HasHeaderPropertyKey =
HeaderedContentControl.HasHeaderPropertyKey;
/// <summary>
/// The DependencyProperty for the HasHeader property.
/// Flags: None
/// Other: Read-Only
/// Default Value: false
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HasHeaderProperty = HeaderedContentControl.HasHeaderProperty.AddOwner(typeof(HeaderedItemsControl));
/// <summary>
/// True if Header is non-null, false otherwise.
/// </summary>
[Bindable(false), Browsable(false)]
public bool HasHeader
{
get { return (bool) GetValue(HasHeaderProperty); }
}
/// <summary>
/// The DependencyProperty for the HeaderTemplate property.
/// Flags: Can be used in style rules
/// Default Value: null
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HeaderTemplateProperty =
HeaderedContentControl.HeaderTemplateProperty.AddOwner(
typeof(HeaderedItemsControl),
new FrameworkPropertyMetadata(
(DataTemplate) null,
new PropertyChangedCallback(OnHeaderTemplateChanged)));
/// <summary>
/// HeaderTemplate is the template used to display the header of each item.
/// </summary>
[Bindable(true), CustomCategory("Content")]
public DataTemplate HeaderTemplate
{
get { return (DataTemplate) GetValue(HeaderTemplateProperty); }
set { SetValue(HeaderTemplateProperty, value); }
}
/// <summary>
/// Called when HeaderTemplateProperty is invalidated on "d."
/// </summary>
private static void OnHeaderTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
HeaderedItemsControl ctrl = (HeaderedItemsControl) d;
ctrl.OnHeaderTemplateChanged((DataTemplate) e.OldValue, (DataTemplate) e.NewValue);
}
/// <summary>
/// This method is invoked when the HeaderTemplate property changes.
/// </summary>
/// <param name="oldHeaderTemplate">The old value of the HeaderTemplate property.</param>
/// <param name="newHeaderTemplate">The new value of the HeaderTemplate property.</param>
protected virtual void OnHeaderTemplateChanged(DataTemplate oldHeaderTemplate, DataTemplate newHeaderTemplate)
{
Helper.CheckTemplateAndTemplateSelector("Header", HeaderTemplateProperty, HeaderTemplateSelectorProperty, this);
}
/// <summary>
/// The DependencyProperty for the HeaderTemplateSelector property.
/// Flags: none
/// Default Value: null
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HeaderTemplateSelectorProperty =
HeaderedContentControl.HeaderTemplateSelectorProperty.AddOwner(
typeof(HeaderedItemsControl),
new FrameworkPropertyMetadata(
(DataTemplateSelector) null,
new PropertyChangedCallback(OnHeaderTemplateSelectorChanged)));
/// <summary>
/// HeaderTemplateSelector allows the application writer to provide custom logic
/// for choosing the template used to display the header of each item.
/// </summary>
/// <remarks>
/// This property is ignored if <seealso cref="HeaderTemplate"/> is set.
/// </remarks>
[Bindable(true), CustomCategory("Content")]
public DataTemplateSelector HeaderTemplateSelector
{
get { return (DataTemplateSelector) GetValue(HeaderTemplateSelectorProperty); }
set { SetValue(HeaderTemplateSelectorProperty, value); }
}
/// <summary>
/// Called when HeaderTemplateSelectorProperty is invalidated on "d."
/// </summary>
private static void OnHeaderTemplateSelectorChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
HeaderedItemsControl ctrl = (HeaderedItemsControl) d;
ctrl.OnHeaderTemplateSelectorChanged((DataTemplateSelector) e.OldValue, (DataTemplateSelector) e.NewValue);
}
/// <summary>
/// This method is invoked when the HeaderTemplateSelector property changes.
/// </summary>
/// <param name="oldHeaderTemplateSelector">The old value of the HeaderTemplateSelector property.</param>
/// <param name="newHeaderTemplateSelector">The new value of the HeaderTemplateSelector property.</param>
protected virtual void OnHeaderTemplateSelectorChanged(DataTemplateSelector oldHeaderTemplateSelector, DataTemplateSelector newHeaderTemplateSelector)
{
Helper.CheckTemplateAndTemplateSelector("Header", HeaderTemplateProperty, HeaderTemplateSelectorProperty, this);
}
/// <summary>
/// The DependencyProperty for the HeaderStringFormat property.
/// Flags: None
/// Default Value: null
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HeaderStringFormatProperty =
DependencyProperty.Register(
"HeaderStringFormat",
typeof(String),
typeof(HeaderedItemsControl),
new FrameworkPropertyMetadata(
(String) null,
new PropertyChangedCallback(OnHeaderStringFormatChanged)));
/// <summary>
/// HeaderStringFormat is the format used to display the header content as a string.
/// This arises only when no template is available.
/// </summary>
[Bindable(true), CustomCategory("Content")]
public String HeaderStringFormat
{
get { return (String) GetValue(HeaderStringFormatProperty); }
set { SetValue(HeaderStringFormatProperty, value); }
}
/// <summary>
/// Called when HeaderStringFormatProperty is invalidated on "d."
/// </summary>
private static void OnHeaderStringFormatChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
HeaderedItemsControl ctrl = (HeaderedItemsControl)d;
ctrl.OnHeaderStringFormatChanged((String) e.OldValue, (String) e.NewValue);
}
/// <summary>
/// This method is invoked when the HeaderStringFormat property changes.
/// </summary>
/// <param name="oldHeaderStringFormat">The old value of the HeaderStringFormat property.</param>
/// <param name="newHeaderStringFormat">The new value of the HeaderStringFormat property.</param>
protected virtual void OnHeaderStringFormatChanged(String oldHeaderStringFormat, String newHeaderStringFormat)
{
}
#endregion
#region Internal Methods
/// <summary>
/// Prepare to display the item.
/// </summary>
internal void PrepareHeaderedItemsControl(object item, ItemsControl parentItemsControl)
{
bool headerIsNotLogical = item != this;
// don't treat Header as a logical child
WriteControlFlag(ControlBoolFlags.HeaderIsNotLogical, headerIsNotLogical);
// copy styles from parent ItemsControl
PrepareItemsControl(item, parentItemsControl);
if (headerIsNotLogical)
{
if (HeaderIsItem || !HasNonDefaultValue(HeaderProperty))
{
Header = item;
HeaderIsItem = true;
}
DataTemplate itemTemplate = parentItemsControl.ItemTemplate;
DataTemplateSelector itemTemplateSelector = parentItemsControl.ItemTemplateSelector;
string itemStringFormat = parentItemsControl.ItemStringFormat;
if (itemTemplate != null)
{
SetValue(HeaderTemplateProperty, itemTemplate);
}
if (itemTemplateSelector != null)
{
SetValue(HeaderTemplateSelectorProperty, itemTemplateSelector);
}
if (itemStringFormat != null &&
Helper.HasDefaultValue(this, HeaderStringFormatProperty))
{
SetValue(HeaderStringFormatProperty, itemStringFormat);
}
PrepareHierarchy(item, parentItemsControl);
}
}
/// <summary>
/// Undo the effect of PrepareHeaderedItemsControl.
/// </summary>
internal void ClearHeaderedItemsControl(object item)
{
ClearItemsControl(item);
if (item != this)
{
if (HeaderIsItem)
{
Header = BindingExpressionBase.DisconnectedItem;
}
}
}
/// <summary>
/// Gives a string representation of this object.
/// </summary>
/// <returns></returns>
internal override string GetPlainText()
{
return ContentControl.ContentObjectToString(Header);
}
#endregion
#region Method Overrides
/// <summary>
/// Gives a string representation of this object.
/// </summary>
public override string ToString()
{
string typeText = this.GetType().ToString();
string headerText = String.Empty;
int itemCount = 0;
bool valuesDefined = false;
// Accessing Header's content may be thread sensitive
if (CheckAccess())
{
headerText = ContentControl.ContentObjectToString(Header);
// HasItems may be wrong when underlying collection does not notify,
// but this function should try to return what's consistent with ItemsControl state.
itemCount = HasItems ? Items.Count : 0;
valuesDefined = true;
}
else
{
//Not on dispatcher, try posting to the dispatcher with 20ms timeout
Dispatcher.Invoke(DispatcherPriority.Send, new TimeSpan(0, 0, 0, 0, 20), new DispatcherOperationCallback(delegate(object o)
{
headerText = ContentControl.ContentObjectToString(Header);
// HasItems may be wrong when underlying collection does not notify,
// but this function should try to return what's consistent with ItemsControl state.
itemCount = HasItems ? Items.Count : 0;
valuesDefined = true;
return null;
}), null);
}
// If header and items count are defined
if (valuesDefined)
{
return SR.Get(SRID.ToStringFormatString_HeaderedItemsControl, typeText, headerText, itemCount);
}
// Not able to access the dispatcher
return typeText;
}
#endregion
#region LogicalTree
/// <summary>
/// Returns enumerator to logical children
/// </summary>
protected internal override IEnumerator LogicalChildren
{
get
{
object header = Header;
if (ReadControlFlag(ControlBoolFlags.HeaderIsNotLogical) || header == null)
{
return base.LogicalChildren;
}
return new HeaderedItemsModelTreeEnumerator(this, base.LogicalChildren, header);
}
}
#endregion
#region Private methods
// As a convenience for hierarchical data, get the header template and
// if it's a HierarchicalDataTemplate, set the ItemsSource, ItemTemplate,
// ItemTemplateSelector, and ItemStringFormat properties from the template.
void PrepareHierarchy(object item, ItemsControl parentItemsControl)
{
// get the effective header template
DataTemplate headerTemplate = HeaderTemplate;
if (headerTemplate == null)
{
DataTemplateSelector selector = HeaderTemplateSelector;
if (selector != null)
{
headerTemplate = selector.SelectTemplate(item, this);
}
if (headerTemplate == null)
{
headerTemplate = (DataTemplate)FindTemplateResourceInternal(this, item, typeof(DataTemplate));
}
}
// if the effective template is a HierarchicalDataTemplate, forward
// the special properties
HierarchicalDataTemplate hTemplate = headerTemplate as HierarchicalDataTemplate;
if (hTemplate != null)
{
bool templateMatches = (ItemTemplate == parentItemsControl.ItemTemplate);
bool containerStyleMatches = (ItemContainerStyle == parentItemsControl.ItemContainerStyle);
if (hTemplate.ItemsSource != null && !HasNonDefaultValue(ItemsSourceProperty))
{
SetBinding(ItemsSourceProperty, hTemplate.ItemsSource);
}
if (hTemplate.IsItemStringFormatSet && ItemStringFormat == parentItemsControl.ItemStringFormat)
{
// if the HDT defines a string format, turn off the
// forwarding of ItemTemplate[Selector] (which would get in the way).
ClearValue(ItemTemplateProperty);
ClearValue(ItemTemplateSelectorProperty);
// forward the HDT's string format
ClearValue(ItemStringFormatProperty);
bool setItemStringFormat = (hTemplate.ItemStringFormat != null);
if (setItemStringFormat)
{
ItemStringFormat = hTemplate.ItemStringFormat;
}
}
if (hTemplate.IsItemTemplateSelectorSet && ItemTemplateSelector == parentItemsControl.ItemTemplateSelector)
{
// if the HDT defines a template selector, turn off the
// forwarding of ItemTemplate (which would get in the way).
ClearValue(ItemTemplateProperty);
// forward the HDT's template selector
ClearValue(ItemTemplateSelectorProperty);
bool setItemTemplateSelector = (hTemplate.ItemTemplateSelector != null);
if (setItemTemplateSelector)
{
ItemTemplateSelector = hTemplate.ItemTemplateSelector;
}
}
if (hTemplate.IsItemTemplateSet && templateMatches)
{
// forward the HDT's template
ClearValue(ItemTemplateProperty);
bool setItemTemplate = (hTemplate.ItemTemplate != null);
if (setItemTemplate)
{
ItemTemplate = hTemplate.ItemTemplate;
}
}
if (hTemplate.IsItemContainerStyleSelectorSet && ItemContainerStyleSelector == parentItemsControl.ItemContainerStyleSelector)
{
// if the HDT defines a container-style selector, turn off the
// forwarding of ItemContainerStyle (which would get in the way).
ClearValue(ItemContainerStyleProperty);
// forward the HDT's container-style selector
ClearValue(ItemContainerStyleSelectorProperty);
bool setItemContainerStyleSelector = (hTemplate.ItemContainerStyleSelector != null);
if (setItemContainerStyleSelector)
{
ItemContainerStyleSelector = hTemplate.ItemContainerStyleSelector;
}
}
if (hTemplate.IsItemContainerStyleSet && containerStyleMatches)
{
// forward the HDT's container style
ClearValue(ItemContainerStyleProperty);
bool setItemContainerStyle = (hTemplate.ItemContainerStyle != null);
if (setItemContainerStyle)
{
ItemContainerStyle = hTemplate.ItemContainerStyle;
}
}
if (hTemplate.IsAlternationCountSet && AlternationCount == parentItemsControl.AlternationCount)
{
// forward the HDT's alternation count
ClearValue(AlternationCountProperty);
bool setAlternationCount = true;
if (setAlternationCount)
{
AlternationCount = hTemplate.AlternationCount;
}
}
if (hTemplate.IsItemBindingGroupSet && ItemBindingGroup == parentItemsControl.ItemBindingGroup)
{
// forward the HDT's ItemBindingGroup
ClearValue(ItemBindingGroupProperty);
bool setItemBindingGroup = (hTemplate.ItemBindingGroup != null);
if (setItemBindingGroup)
{
ItemBindingGroup = hTemplate.ItemBindingGroup;
}
}
}
}
// return true if the dp is bound via the given Binding
bool IsBound(DependencyProperty dp, Binding binding)
{
BindingExpressionBase bindExpr = BindingOperations.GetBindingExpression(this, dp);
return (bindExpr != null && bindExpr.ParentBindingBase == binding);
}
// return true if the Header should be a logical child
bool IsHeaderLogical()
{
// use cached result, if available
if (ReadControlFlag(ControlBoolFlags.HeaderIsNotLogical))
return false;
// if Header property is data-bound, it should not be logical
if (BindingOperations.IsDataBound(this, HeaderProperty))
{
WriteControlFlag(ControlBoolFlags.HeaderIsNotLogical, true);
return false;
}
// otherwise, Header is logical
return true;
}
// return true if the Header is a data item
bool HeaderIsItem
{
get { return ReadControlFlag(ControlBoolFlags.HeaderIsItem); }
set { WriteControlFlag(ControlBoolFlags.HeaderIsItem, value); }
}
#endregion Private methods
}
}
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