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using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Windows.Media;
using System.Windows.Input;
using MS.Internal;
namespace System.Windows
{
internal abstract class ReverseInheritProperty
{
internal ReverseInheritProperty(
DependencyPropertyKey flagKey,
CoreFlags flagCache,
CoreFlags flagChanged)
: this(flagKey, flagCache, flagChanged, CoreFlags.None, CoreFlags.None)
{
}
internal ReverseInheritProperty(
DependencyPropertyKey flagKey,
CoreFlags flagCache,
CoreFlags flagChanged,
CoreFlags flagOldOriginCache,
CoreFlags flagNewOriginCache)
{
FlagKey = flagKey;
FlagCache = flagCache;
FlagChanged = flagChanged;
FlagOldOriginCache = flagOldOriginCache;
FlagNewOriginCache = flagNewOriginCache;
}
internal abstract void FireNotifications(UIElement uie, ContentElement ce, UIElement3D uie3D, bool oldValue);
internal void OnOriginValueChanged(DependencyObject oldOrigin, DependencyObject newOrigin, ref DeferredElementTreeState oldTreeState)
{
OnOriginValueChanged(oldOrigin, newOrigin, null, ref oldTreeState, null);
}
internal void OnOriginValueChanged(DependencyObject oldOrigin,
DependencyObject newOrigin,
IList<DependencyObject> otherOrigins,
ref DeferredElementTreeState oldTreeState,
Action<DependencyObject, bool> originChangedAction)
{
DeferredElementTreeState treeStateLocalCopy = oldTreeState;
oldTreeState = null;
// Determine if one needs to raise notifications of elements
// affected by the origin change irrespective of other origins
bool setOriginCacheFlag = ((originChangedAction != null) &&
(FlagOldOriginCache != CoreFlags.None) &&
(FlagNewOriginCache != CoreFlags.None));
// Step #1
// Update the cache flags for all elements in the ancestry
// of the element that got turned off and record the changed nodes
if (oldOrigin != null)
{
SetCacheFlagInAncestry(oldOrigin, false, treeStateLocalCopy, true, setOriginCacheFlag);
}
// Step #2
// Update the cache flags for all elements in the ancestry
// of the element that got turned on and record the changed nodes
if (newOrigin != null)
{
SetCacheFlagInAncestry(newOrigin, true, null, true, setOriginCacheFlag);
}
int otherCount = (otherOrigins != null) ? otherOrigins.Count : 0;
for (int i = 0; i < otherCount; i++)
{
// setOriginCacheFlag is false, because these flags should not be affected by other origins
SetCacheFlagInAncestry(otherOrigins[i], true, null, false, /*setOriginCacheFlag*/ false);
}
// Step #3
// Fire value changed on elements in the ancestry of the element that got turned off.
if (oldOrigin != null)
{
FirePropertyChangeInAncestry(oldOrigin, true /* oldValue */, treeStateLocalCopy, originChangedAction);
}
// Step #4
// Fire value changed on elements in the ancestry of the element that got turned on.
if (newOrigin != null)
{
FirePropertyChangeInAncestry(newOrigin, false /* oldValue */, null, originChangedAction);
}
if (oldTreeState == null && treeStateLocalCopy != null)
{
// Now that we have applied the old tree state, throw it away.
treeStateLocalCopy.Clear();
oldTreeState = treeStateLocalCopy;
}
}
private void SetCacheFlagInAncestry(DependencyObject element,
bool newValue,
DeferredElementTreeState treeState,
bool shortCircuit,
bool setOriginCacheFlag)
{
UIElement uie;
ContentElement ce;
UIElement3D uie3D;
CastElement(element, out uie, out ce, out uie3D);
bool isFlagSet = IsFlagSet(uie, ce, uie3D, FlagCache);
bool isFlagOriginCacheSet = (setOriginCacheFlag ? IsFlagSet(uie, ce, uie3D, (newValue ? FlagNewOriginCache : FlagOldOriginCache)) : false);
// If the cache flag value is undergoing change, record it and
// propagate the change to the ancestors.
if ((newValue != isFlagSet) ||
(setOriginCacheFlag && !isFlagOriginCacheSet) ||
!shortCircuit)
{
if (newValue != isFlagSet)
{
SetFlag(uie, ce, uie3D, FlagCache, newValue);
// NOTE: we toggle the changed flag instead of setting it so that that way common
// ancestors show resultant unchanged and do not receive any change notification.
SetFlag(uie, ce, uie3D, FlagChanged, !IsFlagSet(uie, ce, uie3D, FlagChanged));
}
if (setOriginCacheFlag && !isFlagOriginCacheSet)
{
SetFlag(uie, ce, uie3D, (newValue ? FlagNewOriginCache : FlagOldOriginCache), true);
}
// Check for block reverse inheritance flag, elements like popup want to set this.
if (BlockReverseInheritance(uie, ce, uie3D))
{
return;
}
// Propagate the flag up the visual and logical trees. Note our
// minimal optimization check to avoid walking both the core
// and logical parents if they are the same.
{
DependencyObject coreParent = DeferredElementTreeState.GetInputElementParent(element, treeState);
DependencyObject logicalParent = DeferredElementTreeState.GetLogicalParent(element, treeState);
if (coreParent != null)
{
SetCacheFlagInAncestry(coreParent, newValue, treeState, shortCircuit, setOriginCacheFlag);
}
if (logicalParent != null && logicalParent != coreParent)
{
SetCacheFlagInAncestry(logicalParent, newValue, treeState, shortCircuit, setOriginCacheFlag);
}
}
}
}
private void FirePropertyChangeInAncestry(DependencyObject element,
bool oldValue,
DeferredElementTreeState treeState,
Action<DependencyObject, bool> originChangedAction)
{
UIElement uie;
ContentElement ce;
UIElement3D uie3D;
CastElement(element, out uie, out ce, out uie3D);
bool flagChanged = IsFlagSet(uie, ce, uie3D, FlagChanged);
bool isFlagOldOriginCacheSet = ((FlagOldOriginCache == CoreFlags.None) ? false : IsFlagSet(uie, ce, uie3D, FlagOldOriginCache));
bool isFlagNewOriginCacheSet = ((FlagNewOriginCache == CoreFlags.None) ? false : IsFlagSet(uie, ce, uie3D, FlagNewOriginCache));
if (flagChanged || isFlagOldOriginCacheSet || isFlagNewOriginCacheSet)
{
if (flagChanged)
{
// if FlagChanged bit is set, then the value has changed effectively
// after considering all the origins. Hence change the property value
// and fire notifications.
SetFlag(uie, ce, uie3D, FlagChanged, false);
if (oldValue)
{
element.ClearValue(FlagKey);
}
else
{
element.SetValue(FlagKey, true);
}
FireNotifications(uie, ce, uie3D, oldValue);
}
if (isFlagOldOriginCacheSet || isFlagNewOriginCacheSet)
{
SetFlag(uie, ce, uie3D, FlagOldOriginCache, false);
SetFlag(uie, ce, uie3D, FlagNewOriginCache, false);
if (isFlagOldOriginCacheSet != isFlagNewOriginCacheSet)
{
// if either FlagOldOriginCache or FlagNewOriginCache
// are set, then the origin change has affected this node
// and hence originChangedAction should be executed.
Debug.Assert(originChangedAction != null);
originChangedAction(element, oldValue);
}
}
// Check for block reverse inheritance flag, elements like popup want to set this.
if (BlockReverseInheritance(uie, ce, uie3D))
{
return;
}
// Call FirePropertyChange up the visual and logical trees.
// Note our minimal optimization check to avoid walking both
// the core and logical parents if they are the same.
{
DependencyObject coreParent = DeferredElementTreeState.GetInputElementParent(element, treeState);
DependencyObject logicalParent = DeferredElementTreeState.GetLogicalParent(element, treeState);
if (coreParent != null)
{
FirePropertyChangeInAncestry(coreParent, oldValue, treeState, originChangedAction);
}
if (logicalParent != null && logicalParent != coreParent)
{
FirePropertyChangeInAncestry(logicalParent, oldValue, treeState, originChangedAction);
}
}
}
}
/////////////////////////////////////////////////////////////////////
private static bool BlockReverseInheritance(UIElement uie, ContentElement ce, UIElement3D uie3D)
{
if (uie != null)
{
return uie.BlockReverseInheritance();
}
else if (ce != null)
{
return ce.BlockReverseInheritance();
}
else if (uie3D != null)
{
return uie3D.BlockReverseInheritance();
}
return false;
}
/////////////////////////////////////////////////////////////////////
private static void SetFlag(UIElement uie, ContentElement ce, UIElement3D uie3D, CoreFlags flag, bool value)
{
if (uie != null)
{
uie.WriteFlag(flag, value);
}
else if (ce != null)
{
ce.WriteFlag(flag, value);
}
else if (uie3D != null)
{
uie3D.WriteFlag(flag, value);
}
}
/////////////////////////////////////////////////////////////////////
private static bool IsFlagSet(UIElement uie, ContentElement ce, UIElement3D uie3D, CoreFlags flag)
{
if (uie != null)
{
return uie.ReadFlag(flag);
}
else if (ce != null)
{
return ce.ReadFlag(flag);
}
else if (uie3D != null)
{
return uie3D.ReadFlag(flag);
}
return false;
}
/////////////////////////////////////////////////////////////////////
private static void CastElement(DependencyObject o, out UIElement uie, out ContentElement ce, out UIElement3D uie3D)
{
uie = o as UIElement;
ce = (uie != null) ? null : o as ContentElement;
uie3D = (uie != null || ce != null) ? null : o as UIElement3D;
}
/////////////////////////////////////////////////////////////////////
protected DependencyPropertyKey FlagKey;
protected CoreFlags FlagCache;
protected CoreFlags FlagChanged;
protected CoreFlags FlagOldOriginCache; // Flag to keep track of elements in the path of old origin
protected CoreFlags FlagNewOriginCache; // Flag to keep track of elements in the path of new origin
}
}
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