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//---------------------------------------------------------------------------
//
// <copyright file="ClrBindingWorker.cs" company="Microsoft">
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
// Description: Defines ClrBindingWorker object, workhorse for CLR bindings
//
//---------------------------------------------------------------------------
using System;
using System.Collections;
using System.Reflection;
using System.Globalization;
using System.Windows.Threading;
using System.Threading;
using System.ComponentModel;
using System.Diagnostics;
using System.Windows;
using System.Windows.Controls; // Validation
using System.Windows.Data;
using System.Windows.Markup; // for GetTypeFromName
using MS.Internal.Controls; // Validation
using MS.Internal.Utility; // for GetTypeFromName
using MS.Utility;
namespace MS.Internal.Data
{
internal class ClrBindingWorker : BindingWorker
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
internal ClrBindingWorker(BindingExpression b, DataBindEngine engine) : base(b)
{
PropertyPath path = ParentBinding.Path;
if (ParentBinding.XPath != null)
{
path = PrepareXmlBinding(path);
}
if (path == null)
{
path = new PropertyPath(String.Empty);
}
if (ParentBinding.Path == null)
{
ParentBinding.UsePath(path);
}
_pathWorker = new PropertyPathWorker(path, this, IsDynamic, engine);
_pathWorker.SetTreeContext(ParentBindingExpression.TargetElementReference);
}
// separate method to avoid loading System.Xml if not needed
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
PropertyPath PrepareXmlBinding(PropertyPath path)
{
if (path == null)
{
DependencyProperty targetDP = TargetProperty;
Type targetType = targetDP.PropertyType;
string pathString;
if (targetType == typeof(Object))
{
if (targetDP == System.Windows.Data.BindingExpression.NoTargetProperty ||
targetDP == System.Windows.Controls.Primitives.Selector.SelectedValueProperty ||
targetDP.OwnerType == typeof(LiveShapingList)
)
{
// these properties want the "value" - i.e. the text of
// the first (and usually only) XmlNode
pathString = "/InnerText";
}
else if (targetDP == FrameworkElement.DataContextProperty ||
targetDP == CollectionViewSource.SourceProperty)
{
// these properties want the entire collection
pathString = String.Empty;
}
else
{
// most object-valued properties want the (current) XmlNode itself
pathString = "/";
}
}
else if (targetType.IsAssignableFrom(typeof(XmlDataCollection)))
{
// these properties want the entire collection
pathString = String.Empty;
}
else
{
// most other properties want the "value"
pathString = "/InnerText";
}
path = new PropertyPath(pathString);
}
// don't bother to create XmlWorker if we don't even have a valid path
if (path.SVI.Length > 0)
{
// tell Xml Worker if desired result is collection, in order to get optimization
SetValue(Feature.XmlWorker, new XmlBindingWorker(this, path.SVI[0].drillIn == DrillIn.Never));
}
return path;
}
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
internal override Type SourcePropertyType
{
get
{
return PW.GetType(PW.Length - 1);
}
}
internal override bool IsDBNullValidForUpdate
{
get
{
return PW.IsDBNullValidForUpdate;
}
}
internal override object SourceItem
{
get
{
return PW.SourceItem;
}
}
internal override string SourcePropertyName
{
get
{
return PW.SourcePropertyName;
}
}
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
internal override bool CanUpdate
{
get
{
PropertyPathWorker ppw = PW;
int k = PW.Length - 1;
if (k < 0)
return false;
object item = ppw.GetItem(k);
if (item == null || item == BindingExpression.NullDataItem)
return false;
object accessor = ppw.GetAccessor(k);
if (accessor == null ||
(accessor == DependencyProperty.UnsetValue && XmlWorker == null))
return false;
return true;
}
}
internal override void AttachDataItem()
{
object item;
if (XmlWorker == null)
{
item = DataItem;
}
else
{
XmlWorker.AttachDataItem();
item = XmlWorker.RawValue();
}
PW.AttachToRootItem(item);
if (PW.Length == 0)
{
ParentBindingExpression.SetupDefaultValueConverter(item.GetType());
}
}
internal override void DetachDataItem()
{
PW.DetachFromRootItem();
if (XmlWorker != null)
{
XmlWorker.DetachDataItem();
}
// cancel any pending async requests. If it has already completed,
// but is now waiting in the dispatcher queue, it will be ignored because
// we set _pending*Request to null.
AsyncGetValueRequest pendingGetValueRequest = (AsyncGetValueRequest)GetValue(Feature.PendingGetValueRequest, null);
if (pendingGetValueRequest != null)
{
pendingGetValueRequest.Cancel();
ClearValue(Feature.PendingGetValueRequest);
}
AsyncSetValueRequest pendingSetValueRequest = (AsyncSetValueRequest)GetValue(Feature.PendingSetValueRequest, null);
if (pendingSetValueRequest != null)
{
pendingSetValueRequest.Cancel();
ClearValue(Feature.PendingSetValueRequest);
}
}
internal override object RawValue()
{
object rawValue = PW.RawValue();
SetStatus(PW.Status);
return rawValue;
}
internal override void RefreshValue()
{
PW.RefreshValue();
}
internal override void UpdateValue(object value)
{
int k = PW.Length - 1;
object item = PW.GetItem(k);
if (item == null || item == BindingExpression.NullDataItem)
return;
// if the binding is async, post a request to set the value
if (ParentBinding.IsAsync && !(PW.GetAccessor(k) is DependencyProperty))
{
RequestAsyncSetValue(item, value);
return;
}
PW.SetValue(item, value);
}
internal override void OnCurrentChanged(ICollectionView collectionView, EventArgs args)
{
if (XmlWorker != null)
XmlWorker.OnCurrentChanged(collectionView, args);
PW.OnCurrentChanged(collectionView);
}
internal override bool UsesDependencyProperty(DependencyObject d, DependencyProperty dp)
{
return PW.UsesDependencyProperty(d, dp);
}
internal override void OnSourceInvalidation(DependencyObject d, DependencyProperty dp, bool isASubPropertyChange)
{
PW.OnDependencyPropertyChanged(d, dp, isASubPropertyChange);
}
internal override bool IsPathCurrent()
{
object item = (XmlWorker == null) ? DataItem : XmlWorker.RawValue();
return PW.IsPathCurrent(item);
}
//------------------------------------------------------
//
// Internal Properties - callbacks from PropertyPathWorker
//
//------------------------------------------------------
internal bool TransfersDefaultValue
{
get { return ParentBinding.TransfersDefaultValue; }
}
internal bool ValidatesOnNotifyDataErrors
{
get { return ParentBindingExpression.ValidatesOnNotifyDataErrors; }
}
//------------------------------------------------------
//
// Internal Methods - callbacks from PropertyPathWorker
//
//------------------------------------------------------
internal void CancelPendingTasks()
{
ParentBindingExpression.CancelPendingTasks();
}
internal bool AsyncGet(object item, int level)
{
if (ParentBinding.IsAsync)
{
RequestAsyncGetValue(item, level);
return true;
}
else
return false;
}
internal void ReplaceCurrentItem(ICollectionView oldCollectionView, ICollectionView newCollectionView)
{
// detach from old view
if (oldCollectionView != null)
{
CurrentChangedEventManager.RemoveHandler(oldCollectionView, ParentBindingExpression.OnCurrentChanged);
if (IsReflective)
{
CurrentChangingEventManager.RemoveHandler(oldCollectionView, ParentBindingExpression.OnCurrentChanging);
}
}
// attach to new view
if (newCollectionView != null)
{
CurrentChangedEventManager.AddHandler(newCollectionView, ParentBindingExpression.OnCurrentChanged);
if (IsReflective)
{
CurrentChangingEventManager.AddHandler(newCollectionView, ParentBindingExpression.OnCurrentChanging);
}
}
}
internal void NewValueAvailable(bool dependencySourcesChanged, bool initialValue, bool isASubPropertyChange)
{
SetStatus(PW.Status);
BindingExpression parent = ParentBindingExpression;
// this method is called when the last item in the path is replaced.
// BindingGroup also wants to know about this.
BindingGroup bindingGroup = parent.BindingGroup;
if (bindingGroup != null)
{
bindingGroup.UpdateTable(parent);
}
if (dependencySourcesChanged)
{
ReplaceDependencySources();
}
if (Status != BindingStatusInternal.AsyncRequestPending)
{
// if there's a revised value (i.e. not during initialization
// and shutdown), transfer it.
if (!initialValue)
{
parent.ScheduleTransfer(isASubPropertyChange);
}
else
{
// "initialValue" should really be called "suppressTransfer".
// It's true when we don't want to transfer the new value:
// a) initial activation
// b) shutdown
// c) DataContext={DisconnectedItem}
// Even in these cases, at least clear the pending flag,
// so that future source changes aren't ignored (DDVSO 850536)
SetTransferIsPending(false);
}
}
}
internal void SetupDefaultValueConverter(Type type)
{
ParentBindingExpression.SetupDefaultValueConverter(type);
}
internal bool IsValidValue(object value)
{
return TargetProperty.IsValidValue(value);
}
internal void OnSourcePropertyChanged(object o, string propName)
{
int level;
// ignore changes that don't affect this binding.
// This test must come before any marshalling to the right context (bug 892484)
if (!IgnoreSourcePropertyChange && (level = PW.LevelForPropertyChange(o, propName)) >= 0)
{
// if notification was on the right thread, just do the work (normal case)
if (Dispatcher.Thread == Thread.CurrentThread)
{
PW.OnPropertyChangedAtLevel(level);
}
else
{
// otherwise invoke an operation to do the work on the right context
SetTransferIsPending(true);
if (ParentBindingExpression.TargetWantsCrossThreadNotifications)
{
LiveShapingItem lsi = TargetElement as LiveShapingItem;
if (lsi != null)
{
lsi.OnCrossThreadPropertyChange(TargetProperty);
}
}
Engine.Marshal(
new DispatcherOperationCallback(ScheduleTransferOperation),
null);
}
}
}
internal void OnDataErrorsChanged(INotifyDataErrorInfo indei, string propName)
{
// if notification was on the right thread, just do the work (normal case)
if (Dispatcher.Thread == Thread.CurrentThread)
{
ParentBindingExpression.UpdateNotifyDataErrors(indei, propName, DependencyProperty.UnsetValue);
}
else if (!ParentBindingExpression.IsDataErrorsChangedPending)
{
// otherwise invoke an operation to do the work on the right context
ParentBindingExpression.IsDataErrorsChangedPending = true;
Engine.Marshal(
(arg) => { object[] args = (object[])arg;
ParentBindingExpression.UpdateNotifyDataErrors((INotifyDataErrorInfo)args[0], (string)args[1], DependencyProperty.UnsetValue);
return null; },
new object[]{indei, propName});
}
}
// called by the child XmlBindingWorker when an xml change is detected
// but the identity of raw value has not changed.
internal void OnXmlValueChanged()
{
// treat this as a property change at the top level
object item = PW.GetItem(0);
OnSourcePropertyChanged(item, null);
}
// called by the child XmlBindingWorker when there's a new raw value
internal void UseNewXmlItem(object item)
{
PW.DetachFromRootItem();
PW.AttachToRootItem(item);
if (Status != BindingStatusInternal.AsyncRequestPending)
{
ParentBindingExpression.ScheduleTransfer(false);
}
}
// called by the child XmlBindingWorker to get the current "result node"
internal object GetResultNode()
{
return PW.GetItem(0);
}
internal DependencyObject CheckTarget()
{
// if the target has been GC'd, this will shut down the binding
return TargetElement;
}
internal void ReportGetValueError(int k, object item, Exception ex)
{
if (TraceData.IsEnabled)
{
SourceValueInfo svi = PW.GetSourceValueInfo(k);
Type type = PW.GetType(k);
string parentName = (k>0)? PW.GetSourceValueInfo(k-1).name : String.Empty;
TraceData.Trace(ParentBindingExpression.TraceLevel,
TraceData.CannotGetClrRawValue(
svi.propertyName, type.Name,
parentName, AvTrace.TypeName(item)),
ParentBindingExpression, ex);
}
}
internal void ReportSetValueError(int k, object item, object value, Exception ex)
{
if (TraceData.IsEnabled)
{
SourceValueInfo svi = PW.GetSourceValueInfo(k);
Type type = PW.GetType(k);
TraceData.Trace(TraceEventType.Error,
TraceData.CannotSetClrRawValue(
svi.propertyName, type.Name,
AvTrace.TypeName(item),
AvTrace.ToStringHelper(value),
AvTrace.TypeName(value)),
ParentBindingExpression, ex);
}
}
internal void ReportRawValueErrors(int k, object item, object info)
{
if (TraceData.IsEnabled)
{
if (item == null)
{
// There is probably no data item; e.g. we've moved currency off of a list.
// the type of the missing item is supposed to be _arySVS[k].info.DeclaringType
// the property we're looking for is named _arySVS[k].name
TraceData.Trace(TraceEventType.Information, TraceData.MissingDataItem, ParentBindingExpression);
}
if (info == null)
{
// this no info problem should have been error reported at ReplaceItem already.
// this can happen when parent is Nullable with no value
// check _arySVS[k-1].info.ComponentType
//if (!IsNullableType(_arySVS[k-1].info.ComponentType))
TraceData.Trace(TraceEventType.Information, TraceData.MissingInfo, ParentBindingExpression);
}
if (item == BindingExpression.NullDataItem)
{
// this is OK, not an error.
// this can happen when detaching bindings.
// this can happen when binding has a Nullable data item with no value
TraceData.Trace(TraceEventType.Information, TraceData.NullDataItem, ParentBindingExpression);
}
}
}
internal void ReportBadXPath(TraceEventType traceType)
{
XmlBindingWorker xmlWorker = XmlWorker;
if (xmlWorker != null)
{
xmlWorker.ReportBadXPath(traceType);
}
}
//------------------------------------------------------
//
// Private Properties
//
//------------------------------------------------------
PropertyPathWorker PW { get { return _pathWorker; } }
XmlBindingWorker XmlWorker { get { return (XmlBindingWorker)GetValue(Feature.XmlWorker, null); } }
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
void SetStatus(PropertyPathStatus status)
{
switch (status)
{
case PropertyPathStatus.Inactive:
Status = BindingStatusInternal.Inactive;
break;
case PropertyPathStatus.Active:
Status = BindingStatusInternal.Active;
break;
case PropertyPathStatus.PathError:
Status = BindingStatusInternal.PathError;
break;
case PropertyPathStatus.AsyncRequestPending:
Status = BindingStatusInternal.AsyncRequestPending;
break;
}
}
void ReplaceDependencySources()
{
if (!ParentBindingExpression.IsDetaching)
{
int size = PW.Length;
if (PW.NeedsDirectNotification)
++size;
WeakDependencySource[] newSources = new WeakDependencySource[size];
int n = 0;
if (IsDynamic)
{
for (int k=0; k<PW.Length; ++k)
{
DependencyProperty dp = PW.GetAccessor(k) as DependencyProperty;
if (dp != null)
{
DependencyObject d = PW.GetItem(k) as DependencyObject;
if (d != null)
newSources[n++] = new WeakDependencySource(d, dp);
}
}
if (PW.NeedsDirectNotification)
{
// subproperty notifications can only arise from Freezables
// (as of today - 11/14/08), so we only need to propagate
// them when the raw value is a Freezable.
DependencyObject d = PW.RawValue() as Freezable;
if (d != null)
newSources[n++] = new WeakDependencySource(d, DependencyObject.DirectDependencyProperty);
}
}
ParentBindingExpression.ChangeWorkerSources(newSources, n);
}
}
#region Async
void RequestAsyncGetValue(object item, int level)
{
// get information about the property whose value we want
string name = GetNameFromInfo(PW.GetAccessor(level));
Invariant.Assert(name != null, "Async GetValue expects a name");
// abandon any previous request
AsyncGetValueRequest pendingGetValueRequest = (AsyncGetValueRequest)GetValue(Feature.PendingGetValueRequest, null);
if (pendingGetValueRequest != null)
{
pendingGetValueRequest.Cancel();
}
// issue the new request
pendingGetValueRequest =
new AsyncGetValueRequest(item, name, ParentBinding.AsyncState,
DoGetValueCallback, CompleteGetValueCallback,
this, level);
SetValue(Feature.PendingGetValueRequest, pendingGetValueRequest);
Engine.AddAsyncRequest(TargetElement, pendingGetValueRequest);
}
static object OnGetValueCallback(AsyncDataRequest adr)
{
AsyncGetValueRequest request = (AsyncGetValueRequest)adr;
ClrBindingWorker worker = (ClrBindingWorker)request.Args[0];
object value = worker.PW.GetValue(request.SourceItem, (int)request.Args[1]);
if (value == PropertyPathWorker.IListIndexOutOfRange)
throw new ArgumentOutOfRangeException("index");
return value;
}
static object OnCompleteGetValueCallback(AsyncDataRequest adr)
{
AsyncGetValueRequest request = (AsyncGetValueRequest)adr;
ClrBindingWorker worker = (ClrBindingWorker)request.Args[0];
DataBindEngine engine = worker.Engine;
if (engine != null) // could be null if binding has been detached
{
engine.Marshal(CompleteGetValueLocalCallback, request);
}
return null;
}
static object OnCompleteGetValueOperation(object arg)
{
AsyncGetValueRequest request = (AsyncGetValueRequest)arg;
ClrBindingWorker worker = (ClrBindingWorker)request.Args[0];
worker.CompleteGetValue(request);
return null;
}
void CompleteGetValue(AsyncGetValueRequest request)
{
AsyncGetValueRequest pendingGetValueRequest = (AsyncGetValueRequest)GetValue(Feature.PendingGetValueRequest, null);
if (pendingGetValueRequest == request)
{
ClearValue(Feature.PendingGetValueRequest);
int k = (int)request.Args[1];
// if the target has gone away, ignore the request (DDVSO 195760)
if (CheckTarget() == null)
return;
switch (request.Status)
{
case AsyncRequestStatus.Completed:
PW.OnNewValue(k, request.Result);
SetStatus(PW.Status);
if (k == PW.Length - 1)
ParentBindingExpression.TransferValue(request.Result, false);
break;
case AsyncRequestStatus.Failed:
ReportGetValueError(k, request.SourceItem, request.Exception);
PW.OnNewValue(k, DependencyProperty.UnsetValue);
break;
}
}
}
void RequestAsyncSetValue(object item, object value)
{
// get information about the property whose value we want
string name = GetNameFromInfo(PW.GetAccessor(PW.Length-1));
Invariant.Assert(name != null, "Async SetValue expects a name");
// abandon any previous request
AsyncSetValueRequest pendingSetValueRequest = (AsyncSetValueRequest)GetValue(Feature.PendingSetValueRequest, null);
if (pendingSetValueRequest != null)
{
pendingSetValueRequest.Cancel();
}
// issue the new request
pendingSetValueRequest =
new AsyncSetValueRequest(item, name, value, ParentBinding.AsyncState,
DoSetValueCallback, CompleteSetValueCallback,
this);
SetValue(Feature.PendingSetValueRequest, pendingSetValueRequest);
Engine.AddAsyncRequest(TargetElement, pendingSetValueRequest);
}
static object OnSetValueCallback(AsyncDataRequest adr)
{
AsyncSetValueRequest request = (AsyncSetValueRequest)adr;
ClrBindingWorker worker = (ClrBindingWorker)request.Args[0];
worker.PW.SetValue(request.TargetItem, request.Value);
return null;
}
static object OnCompleteSetValueCallback(AsyncDataRequest adr)
{
AsyncSetValueRequest request = (AsyncSetValueRequest)adr;
ClrBindingWorker worker = (ClrBindingWorker)request.Args[0];
DataBindEngine engine = worker.Engine;
if (engine != null) // could be null if binding has been detached
{
engine.Marshal(CompleteSetValueLocalCallback, request);
}
return null;
}
static object OnCompleteSetValueOperation(object arg)
{
AsyncSetValueRequest request = (AsyncSetValueRequest)arg;
ClrBindingWorker worker = (ClrBindingWorker)request.Args[0];
worker.CompleteSetValue(request);
return null;
}
void CompleteSetValue(AsyncSetValueRequest request)
{
AsyncSetValueRequest pendingSetValueRequest = (AsyncSetValueRequest)GetValue(Feature.PendingSetValueRequest, null);
if (pendingSetValueRequest == request)
{
ClearValue(Feature.PendingSetValueRequest);
// if the target has gone away, ignore the request (DDVSO 195760)
if (CheckTarget() == null)
return;
switch (request.Status)
{
case AsyncRequestStatus.Completed:
break;
case AsyncRequestStatus.Failed:
object filteredException = ParentBinding.DoFilterException(ParentBindingExpression, request.Exception);
Exception exception = filteredException as Exception;
ValidationError validationError;
if (exception != null)
{
if (TraceData.IsEnabled)
{
int k = PW.Length - 1;
object value = request.Value;
ReportSetValueError(k, request.TargetItem, request.Value, exception);
}
}
else if ( (validationError = filteredException as ValidationError) != null )
{
Validation.MarkInvalid(ParentBindingExpression, validationError);
}
break;
}
}
}
string GetNameFromInfo(object info)
{
MemberInfo mi;
PropertyDescriptor pd;
DynamicObjectAccessor doa;
if ((mi = info as MemberInfo) != null)
return mi.Name;
if ((pd = info as PropertyDescriptor) != null)
return pd.Name;
if ((doa = info as DynamicObjectAccessor) != null)
return doa.PropertyName;
return null;
}
#endregion Async
#region Callbacks
private object ScheduleTransferOperation(object arg)
{
PW.RefreshValue();
return null;
}
#endregion Callbacks
//------------------------------------------------------
//
// Private Enums, Structs, Constants
//
//------------------------------------------------------
static readonly AsyncRequestCallback DoGetValueCallback = new AsyncRequestCallback(OnGetValueCallback);
static readonly AsyncRequestCallback CompleteGetValueCallback = new AsyncRequestCallback(OnCompleteGetValueCallback);
static readonly DispatcherOperationCallback CompleteGetValueLocalCallback = new DispatcherOperationCallback(OnCompleteGetValueOperation);
static readonly AsyncRequestCallback DoSetValueCallback = new AsyncRequestCallback(OnSetValueCallback);
static readonly AsyncRequestCallback CompleteSetValueCallback = new AsyncRequestCallback(OnCompleteSetValueCallback);
static readonly DispatcherOperationCallback CompleteSetValueLocalCallback = new DispatcherOperationCallback(OnCompleteSetValueOperation);
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
PropertyPathWorker _pathWorker;
}
internal class WeakDependencySource
{
internal WeakDependencySource(DependencyObject item, DependencyProperty dp)
{
_item = BindingExpressionBase.CreateReference(item);
_dp = dp;
}
internal WeakDependencySource(WeakReference wr, DependencyProperty dp)
{
_item = wr;
_dp = dp;
}
internal DependencyObject DependencyObject { get { return (DependencyObject)BindingExpressionBase.GetReference(_item); } }
internal DependencyProperty DependencyProperty { get { return _dp; } }
object _item;
DependencyProperty _dp;
}
}
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