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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;
using System.ComponentModel;
using System.Windows.Data;
using System.Windows.Threading;
using System.Windows.Media;
using MS.Internal;
using MS.Internal.Controls;
using MS.Internal.KnownBoxes;
using MS.Internal.PresentationFramework;
namespace System.Windows.Controls
{
/// <summary>
/// The base class for all controls that contain single content and have a header.
/// </summary>
/// <remarks>
/// HeaderedContentControl adds Header, HasHeader, HeaderTemplate, and HeaderTemplateSelector features to a ContentControl.
/// </remarks>
[Localizability(LocalizationCategory.Text)] // can contain localizable text
public class HeaderedContentControl : ContentControl
{
#region Constructors
static HeaderedContentControl()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(HeaderedContentControl), new FrameworkPropertyMetadata(typeof(HeaderedContentControl)));
_dType = DependencyObjectType.FromSystemTypeInternal(typeof(HeaderedContentControl));
}
/// <summary>
/// Default DependencyObject constructor
/// </summary>
public HeaderedContentControl() : base()
{
}
#endregion
#region Properties
/// <summary>
/// The DependencyProperty for the Header property.
/// Flags: None
/// Default Value: null
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HeaderProperty =
DependencyProperty.Register(
"Header",
typeof(object),
typeof(HeaderedContentControl),
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), Category("Content")]
[Localizability(LocalizationCategory.Label)]
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)
{
HeaderedContentControl ctrl = (HeaderedContentControl) 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)
{
RemoveLogicalChild(oldHeader);
AddLogicalChild(newHeader);
}
/// <summary>
/// The key needed set a read-only property.
/// </summary>
internal static readonly DependencyPropertyKey HasHeaderPropertyKey =
DependencyProperty.RegisterReadOnly(
"HasHeader",
typeof(bool),
typeof(HeaderedContentControl),
new FrameworkPropertyMetadata(BooleanBoxes.FalseBox));
/// <summary>
/// The DependencyProperty for the HasHeader property.
/// Flags: None
/// Other: Read-Only
/// Default Value: false
/// </summary>
[CommonDependencyProperty]
public static readonly DependencyProperty HasHeaderProperty =
HasHeaderPropertyKey.DependencyProperty;
/// <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 =
DependencyProperty.Register(
"HeaderTemplate",
typeof(DataTemplate),
typeof(HeaderedContentControl),
new FrameworkPropertyMetadata(
(DataTemplate) null,
new PropertyChangedCallback(OnHeaderTemplateChanged)));
/// <summary>
/// HeaderTemplate is the template used to display the <seealso cref="Header"/>.
/// </summary>
[Bindable(true), Category("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)
{
HeaderedContentControl ctrl = (HeaderedContentControl)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 =
DependencyProperty.Register(
"HeaderTemplateSelector",
typeof(DataTemplateSelector),
typeof(HeaderedContentControl),
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 <seealso cref="Header"/>.
/// </summary>
/// <remarks>
/// This property is ignored if <seealso cref="HeaderTemplate"/> is set.
/// </remarks>
[Bindable(true), Category("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)
{
HeaderedContentControl ctrl = (HeaderedContentControl) 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(HeaderedContentControl),
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)
{
HeaderedContentControl ctrl = (HeaderedContentControl)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 LogicalTree
/// <summary>
/// Returns enumerator to logical children
/// </summary>
protected internal override IEnumerator LogicalChildren
{
get
{
object header = Header;
if (HeaderIsNotLogical || header == null)
{
return base.LogicalChildren;
}
return new HeaderedContentModelTreeEnumerator(this, ContentIsNotLogical ? null : Content, header);
}
}
#endregion
#region Internal Methods
/// <summary>
/// Gives a string representation of this object.
/// </summary>
/// <returns></returns>
internal override string GetPlainText()
{
return ContentControl.ContentObjectToString(Header);
}
/// <summary>
/// Indicates whether Header should be a logical child or not.
/// </summary>
internal bool HeaderIsNotLogical
{
get { return ReadControlFlag(ControlBoolFlags.HeaderIsNotLogical); }
set { WriteControlFlag(ControlBoolFlags.HeaderIsNotLogical, value); }
}
/// <summary>
/// Indicates whether Header is a data item
/// </summary>
internal bool HeaderIsItem
{
get { return ReadControlFlag(ControlBoolFlags.HeaderIsItem); }
set { WriteControlFlag(ControlBoolFlags.HeaderIsItem, value); }
}
/// <summary>
/// Prepare to display the item.
/// </summary>
internal void PrepareHeaderedContentControl(object item,
DataTemplate itemTemplate,
DataTemplateSelector itemTemplateSelector,
string stringFormat)
{
if (item != this)
{
// don't treat Content as a logical child
ContentIsNotLogical = true;
HeaderIsNotLogical = true;
if (ContentIsItem || !HasNonDefaultValue(ContentProperty))
{
Content = item;
ContentIsItem = true;
}
// Visuals can't be placed in both Header and Content, but data can
if (!(item is Visual) && (HeaderIsItem || !HasNonDefaultValue(HeaderProperty)))
{
Header = item;
HeaderIsItem = true;
}
if (itemTemplate != null)
SetValue(HeaderTemplateProperty, itemTemplate);
if (itemTemplateSelector != null)
SetValue(HeaderTemplateSelectorProperty, itemTemplateSelector);
if (stringFormat != null)
SetValue(HeaderStringFormatProperty, stringFormat);
}
else
{
ContentIsNotLogical = false;
}
}
/// <summary>
/// Undo the effect of PrepareHeaderedContentControl.
/// </summary>
internal void ClearHeaderedContentControl(object item)
{
if (item != this)
{
if (ContentIsItem)
{
Content = BindingExpressionBase.DisconnectedItem;
}
if (HeaderIsItem)
{
Header = BindingExpressionBase.DisconnectedItem;
}
}
}
#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;
string contentText = String.Empty;
bool valuesDefined = false;
// Accessing Header's content may be thread sensitive
if (CheckAccess())
{
headerText = ContentControl.ContentObjectToString(Header);
contentText = ContentControl.ContentObjectToString(Content);
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);
contentText = ContentControl.ContentObjectToString(Content);
valuesDefined = true;
return null;
}), null);
}
// If header and content text are defined
if (valuesDefined)
{
return SR.Format(SR.ToStringFormatString_HeaderedContentControl, typeText, headerText, contentText);
}
// Not able to access the dispatcher
return typeText;
}
#endregion
#region DTypeThemeStyleKey
// Returns the DependencyObjectType for the registered DefaultStyleKey's default
// value. Controls will override this method to return approriate types.
internal override DependencyObjectType DTypeThemeStyleKey
{
get { return _dType; }
}
private static DependencyObjectType _dType;
#endregion DTypeThemeStyleKey
}
}
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