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//---------------------------------------------------------------------------
//
// <copyright file="MultiBinding.cs" company="Microsoft">
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
// Description: Defines MultiBinding object, uses a collection of bindings together.
//
// Specs: http://avalon/connecteddata/M5%20Specs/UIBinding.mht
//
//---------------------------------------------------------------------------
using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Diagnostics;
using System.Globalization;
using System.Windows.Controls; // Validation
using System.Windows.Markup;
using MS.Internal.Controls; // Validation
using MS.Internal.Data;
using MS.Utility;
namespace System.Windows.Data
{
/// <summary>
/// Describes a collection of bindings attached to a single property.
/// The inner bindings contribute their values to the MultiBinding,
/// which combines/converts them into a resultant final value.
/// In the reverse direction, the target value is tranlated to
/// a set of values that are fed back into the inner bindings.
/// </summary>
[ContentProperty("Bindings")]
public class MultiBinding : BindingBase, IAddChild
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
/// <summary> Default constructor </summary>
public MultiBinding()
{
_bindingCollection = new BindingCollection(this, new BindingCollectionChangedCallback(OnBindingCollectionChanged));
}
#region IAddChild
///<summary>
/// Called to Add the object as a Child.
///</summary>
///<param name="value">
/// Object to add as a child - must have type BindingBase
///</param>
void IAddChild.AddChild(Object value)
{
BindingBase binding = value as BindingBase;
if (binding != null)
Bindings.Add(binding);
else
throw new ArgumentException(SR.Get(SRID.ChildHasWrongType, this.GetType().Name, "BindingBase", value.GetType().FullName), "value");
}
///<summary>
/// Called when text appears under the tag in markup
///</summary>
///<param name="text">
/// Text to Add to the Object
///</param>
void IAddChild.AddText(string text)
{
XamlSerializerUtil.ThrowIfNonWhiteSpaceInAddText(text, this);
}
#endregion IAddChild
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
/// <summary> List of inner bindings </summary>
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public Collection<BindingBase> Bindings
{
get { return _bindingCollection; }
}
/// <summary>
/// This method is used by TypeDescriptor to determine if this property should
/// be serialized.
/// </summary>
[EditorBrowsable(EditorBrowsableState.Never)]
public bool ShouldSerializeBindings()
{
return (Bindings != null && Bindings.Count > 0);
}
/// <summary> Binding type </summary>
[DefaultValue(BindingMode.Default)]
public BindingMode Mode
{
get
{
switch (GetFlagsWithinMask(BindingFlags.PropagationMask))
{
case BindingFlags.OneWay: return BindingMode.OneWay;
case BindingFlags.TwoWay: return BindingMode.TwoWay;
case BindingFlags.OneWayToSource: return BindingMode.OneWayToSource;
case BindingFlags.OneTime: return BindingMode.OneTime;
case BindingFlags.PropDefault: return BindingMode.Default;
}
Debug.Assert(false, "Unexpected BindingMode value");
return 0;
}
set
{
CheckSealed();
ChangeFlagsWithinMask(BindingFlags.PropagationMask, FlagsFrom(value));
}
}
/// <summary> Update type </summary>
[DefaultValue(UpdateSourceTrigger.PropertyChanged)]
public UpdateSourceTrigger UpdateSourceTrigger
{
get
{
switch (GetFlagsWithinMask(BindingFlags.UpdateMask))
{
case BindingFlags.UpdateOnPropertyChanged: return UpdateSourceTrigger.PropertyChanged;
case BindingFlags.UpdateOnLostFocus: return UpdateSourceTrigger.LostFocus;
case BindingFlags.UpdateExplicitly: return UpdateSourceTrigger.Explicit;
case BindingFlags.UpdateDefault: return UpdateSourceTrigger.Default;
}
Debug.Assert(false, "Unexpected UpdateSourceTrigger value");
return 0;
}
set
{
CheckSealed();
ChangeFlagsWithinMask(BindingFlags.UpdateMask, FlagsFrom(value));
}
}
/// <summary> Raise SourceUpdated event whenever a value flows from target to source </summary>
[DefaultValue(false)]
public bool NotifyOnSourceUpdated
{
get
{
return TestFlag(BindingFlags.NotifyOnSourceUpdated);
}
set
{
bool currentValue = TestFlag(BindingFlags.NotifyOnSourceUpdated);
if (currentValue != value)
{
CheckSealed();
ChangeFlag(BindingFlags.NotifyOnSourceUpdated, value);
}
}
}
/// <summary> Raise TargetUpdated event whenever a value flows from source to target </summary>
[DefaultValue(false)]
public bool NotifyOnTargetUpdated
{
get
{
return TestFlag(BindingFlags.NotifyOnTargetUpdated);
}
set
{
bool currentValue = TestFlag(BindingFlags.NotifyOnTargetUpdated);
if (currentValue != value)
{
CheckSealed();
ChangeFlag(BindingFlags.NotifyOnTargetUpdated, value);
}
}
}
/// <summary> Raise ValidationError event whenever there is a ValidationError on Update</summary>
[DefaultValue(false)]
public bool NotifyOnValidationError
{
get
{
return TestFlag(BindingFlags.NotifyOnValidationError);
}
set
{
bool currentValue = TestFlag(BindingFlags.NotifyOnValidationError);
if (currentValue != value)
{
CheckSealed();
ChangeFlag(BindingFlags.NotifyOnValidationError, value);
}
}
}
/// <summary> Converter to convert the source values to/from the target value</summary>
[DefaultValue(null)]
public IMultiValueConverter Converter
{
get { return (IMultiValueConverter)GetValue(Feature.Converter, null); }
set { CheckSealed(); SetValue(Feature.Converter, value, null); }
}
/// <summary>
/// The parameter to pass to converter.
/// </summary>
/// <value></value>
[DefaultValue(null)]
public object ConverterParameter
{
get { return GetValue(Feature.ConverterParameter, null); }
set { CheckSealed(); SetValue(Feature.ConverterParameter, value, null); }
}
/// <summary> Culture in which to evaluate the converter </summary>
[DefaultValue(null)]
[TypeConverter(typeof(System.Windows.CultureInfoIetfLanguageTagConverter))]
public CultureInfo ConverterCulture
{
get { return (CultureInfo)GetValue(Feature.Culture, null); }
set { CheckSealed(); SetValue(Feature.Culture, value, null); }
}
/// <summary>
/// Collection<ValidationRule> is a collection of ValidationRule
/// instances on either a Binding or a MultiBinding. Each of the rules
/// is checked for validity on update
/// </summary>
public Collection<ValidationRule> ValidationRules
{
get
{
if (!HasValue(Feature.ValidationRules))
SetValue(Feature.ValidationRules, new ValidationRuleCollection());
return (ValidationRuleCollection)GetValue(Feature.ValidationRules, null);
}
}
/// <summary>
/// This method is used by TypeDescriptor to determine if this property should
/// be serialized.
/// </summary>
[EditorBrowsable(EditorBrowsableState.Never)]
public bool ShouldSerializeValidationRules()
{
return (HasValue(Feature.ValidationRules) && ValidationRules.Count > 0);
}
/// <summary>
/// called whenever any exception is encountered when trying to update
/// the value to the source. The application author can provide its own
/// handler for handling exceptions here. If the delegate returns
/// null - don’t throw an error or provide a ValidationError.
/// Exception - returns the exception itself, we will fire the exception using Async exception model.
/// ValidationError - it will set itself as the BindingInError and add it to the element’s Validation errors.
/// </summary>
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public UpdateSourceExceptionFilterCallback UpdateSourceExceptionFilter
{
get { return (UpdateSourceExceptionFilterCallback)GetValue(Feature.ExceptionFilterCallback, null); }
set { SetValue(Feature.ExceptionFilterCallback, value, null); }
}
/// <summary> True if an exception during source updates should be considered a validation error.</summary>
[DefaultValue(false)]
public bool ValidatesOnExceptions
{
get
{
return TestFlag(BindingFlags.ValidatesOnExceptions);
}
set
{
bool currentValue = TestFlag(BindingFlags.ValidatesOnExceptions);
if (currentValue != value)
{
CheckSealed();
ChangeFlag(BindingFlags.ValidatesOnExceptions, value);
}
}
}
/// <summary> True if a data error in the source item should be considered a validation error.</summary>
[DefaultValue(false)]
public bool ValidatesOnDataErrors
{
get
{
return TestFlag(BindingFlags.ValidatesOnDataErrors);
}
set
{
bool currentValue = TestFlag(BindingFlags.ValidatesOnDataErrors);
if (currentValue != value)
{
CheckSealed();
ChangeFlag(BindingFlags.ValidatesOnDataErrors, value);
}
}
}
/// <summary> True if a data error from INotifyDataErrorInfo source item should be considered a validation error.</summary>
[DefaultValue(true)]
public bool ValidatesOnNotifyDataErrors
{
get
{
return TestFlag(BindingFlags.ValidatesOnNotifyDataErrors);
}
set
{
bool currentValue = TestFlag(BindingFlags.ValidatesOnNotifyDataErrors);
if (currentValue != value)
{
CheckSealed();
ChangeFlag(BindingFlags.ValidatesOnNotifyDataErrors, value);
}
}
}
//------------------------------------------------------
//
// Protected Methods
//
//------------------------------------------------------
/// <summary>
/// Create an appropriate expression for this Binding, to be attached
/// to the given DependencyProperty on the given DependencyObject.
/// </summary>
internal override BindingExpressionBase CreateBindingExpressionOverride(DependencyObject target, DependencyProperty dp, BindingExpressionBase owner)
{
if (Converter == null && String.IsNullOrEmpty(StringFormat))
throw new InvalidOperationException(SR.Get(SRID.MultiBindingHasNoConverter));
for (int i = 0; i < Bindings.Count; ++i)
{
CheckTrigger(Bindings[i]);
}
return MultiBindingExpression.CreateBindingExpression(target, dp, this, owner);
}
internal override ValidationRule LookupValidationRule(Type type)
{
return LookupValidationRule(type, ValidationRulesInternal);
}
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
internal object DoFilterException(object bindExpr, Exception exception)
{
UpdateSourceExceptionFilterCallback callback = (UpdateSourceExceptionFilterCallback)GetValue(Feature.ExceptionFilterCallback, null);
if (callback != null)
return callback(bindExpr, exception);
return exception;
}
internal static void CheckTrigger(BindingBase bb)
{
Binding binding = bb as Binding;
if (binding != null)
{
if (binding.UpdateSourceTrigger != UpdateSourceTrigger.PropertyChanged &&
binding.UpdateSourceTrigger != UpdateSourceTrigger.Default)
throw new InvalidOperationException(SR.Get(SRID.NoUpdateSourceTriggerForInnerBindingOfMultiBinding));
}
}
internal override BindingBase CreateClone()
{
return new MultiBinding();
}
internal override void InitializeClone(BindingBase baseClone, BindingMode mode)
{
MultiBinding clone = (MultiBinding)baseClone;
CopyValue(Feature.Converter, clone);
CopyValue(Feature.ConverterParameter, clone);
CopyValue(Feature.Culture, clone);
CopyValue(Feature.ValidationRules, clone);
CopyValue(Feature.ExceptionFilterCallback, clone);
for (int i=0; i<=_bindingCollection.Count; ++i)
{
clone._bindingCollection.Add(_bindingCollection[i].Clone(mode));
}
base.InitializeClone(baseClone, mode);
}
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
// same as the public ValidationRules property, but
// doesn't try to create an instance if there isn't one there
internal override Collection<ValidationRule> ValidationRulesInternal
{
get
{
return (ValidationRuleCollection)GetValue(Feature.ValidationRules, null);
}
}
internal override CultureInfo ConverterCultureInternal
{
get { return ConverterCulture; }
}
internal override bool ValidatesOnNotifyDataErrorsInternal
{
get { return ValidatesOnNotifyDataErrors; }
}
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
private void OnBindingCollectionChanged()
{
CheckSealed();
}
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
BindingCollection _bindingCollection;
}
}
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