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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.Specialized;
using System.ComponentModel;
using System.IO;
using System.Windows.Markup;
using MS.Utility;
using System;
using System.Diagnostics;
namespace System.Windows
{
/// <summary>
/// A multiple Style property conditional dependency driver
/// </summary>
[ContentProperty("Setters")]
public sealed class MultiTrigger : TriggerBase, IAddChild
{
/// <summary>
/// Conditions collection
/// </summary>
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public ConditionCollection Conditions
{
get
{
// Verify Context Access
VerifyAccess();
return _conditions;
}
}
/// <summary>
/// Collection of Setter objects, which describes what to apply
/// when this trigger is active.
/// </summary>
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public SetterBaseCollection Setters
{
get
{
// Verify Context Access
VerifyAccess();
if( _setters == null )
{
_setters = new SetterBaseCollection();
}
return _setters;
}
}
///<summary>
/// This method is called to Add a Setter object as a child of the Style.
///</summary>
///<param name="value">
/// The object to add as a child; it must be a Setter or subclass.
///</param>
void IAddChild.AddChild (Object value)
{
// Verify Context Access
VerifyAccess();
Setters.Add(Trigger.CheckChildIsSetter(value));
}
///<summary>
/// This method is called by the parser when text appears under the tag in markup.
/// As default Styles do not support text, calling this method has no effect.
///</summary>
///<param name="text">
/// Text to add as a child.
///</param>
void IAddChild.AddText (string text)
{
// Verify Context Access
VerifyAccess();
XamlSerializerUtil.ThrowIfNonWhiteSpaceInAddText(text, this);
}
internal override void Seal()
{
if (IsSealed)
{
return;
}
// Process the _setters collection: Copy values into PropertyValueList and seal the Setter objects.
ProcessSettersCollection(_setters);
if (_conditions.Count > 0)
{
// Seal conditions
_conditions.Seal(ValueLookupType.Trigger);
}
// Build conditions array from collection
TriggerConditions = new TriggerCondition[_conditions.Count];
for (int i = 0; i < TriggerConditions.Length; i++)
{
TriggerConditions[i] = new TriggerCondition(
_conditions[i].Property,
LogicalOp.Equals,
_conditions[i].Value,
(_conditions[i].SourceName != null) ? _conditions[i].SourceName : StyleHelper.SelfName);
}
// Set conditions array for all property triggers
for (int i = 0; i < PropertyValues.Count; i++)
{
PropertyValue propertyValue = PropertyValues[i];
propertyValue.Conditions = TriggerConditions;
// Put back modified struct
PropertyValues[i] = propertyValue;
}
base.Seal();
}
// evaluate the current state of the trigger
internal override bool GetCurrentState(DependencyObject container, UncommonField<HybridDictionary[]> dataField)
{
bool retVal = (TriggerConditions.Length > 0);
for( int i = 0; retVal && i < TriggerConditions.Length; i++ )
{
Debug.Assert( TriggerConditions[i].SourceChildIndex == 0,
"This method was created to handle properties on the containing object, more work is needed to handle templated children too." );
retVal = TriggerConditions[i].Match(container.GetValue(TriggerConditions[i].Property));
}
return retVal;
}
private ConditionCollection _conditions = new ConditionCollection();
private SetterBaseCollection _setters = null;
}
}
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