public static void EnumerateTree(Visual reference, EnumerateTreeFilterCallback filterCallback,
EnumerateTreeResultCallback enumeratorCallback, object misc)
{
if (reference == null)
{
throw new ArgumentNullException("reference");
}
DoEnumerateTree(reference, filterCallback, enumeratorCallback, misc);
}
static bool DoEnumerateTree(object reference, EnumerateTreeFilterCallback filterCallback,
EnumerateTreeResultCallback enumeratorCallback, object misc)
{
for (var i = 0; i < CommonTreeHelper.GetChildrenCount(reference); ++i)
{
var child = CommonTreeHelper.GetChild(reference, i);
var filterResult = HitTestFilterBehavior.Continue;
if (filterCallback != null)
{
filterResult = filterCallback(child, misc);
}
var enumerateSelf = true;
var enumerateChildren = true;
switch (filterResult)
{
case HitTestFilterBehavior.Continue:
break;
case HitTestFilterBehavior.ContinueSkipChildren:
enumerateChildren = false;
break;
case HitTestFilterBehavior.ContinueSkipSelf:
enumerateSelf = false;
break;
case HitTestFilterBehavior.ContinueSkipSelfAndChildren:
enumerateChildren = false;
enumerateSelf = false;
break;
default:
return(false);
}
if
(
(enumerateSelf && enumeratorCallback != null &&
enumeratorCallback(child, misc) == HitTestResultBehavior.Stop) ||
(enumerateChildren && !DoEnumerateTree(child, filterCallback, enumeratorCallback, misc))
)
{
return(false);
}
}
return(true);
}
private static bool DoEnumerateTree(DependencyObject reference, EnumerateTreeFilterCallback filterCallback, EnumerateTreeResultCallback enumeratorCallback, object misc)
{
for (var i = 0; i < VisualTreeHelper.GetChildrenCount(reference); ++i)
{
var child = VisualTreeHelper.GetChild(reference, i);
var filterResult = filterCallback?.Invoke(child, misc) ?? HitTestFilterBehavior.Continue;
var enumerateSelf = true;
var enumerateChildren = true;
switch (filterResult)
{
case HitTestFilterBehavior.Continue:
break;
case HitTestFilterBehavior.ContinueSkipChildren:
enumerateChildren = false;
break;
case HitTestFilterBehavior.ContinueSkipSelf:
enumerateSelf = false;
break;
case HitTestFilterBehavior.ContinueSkipSelfAndChildren:
enumerateChildren = false;
enumerateSelf = false;
break;
default:
return(false);
}
if ((enumerateSelf && enumeratorCallback?.Invoke(child, misc) == HitTestResultBehavior.Stop) ||
(enumerateChildren && DoEnumerateTree(child, filterCallback, enumeratorCallback, misc) == false))
{
return(false);
}
}
return(true);
}
public static void EnumerateTree(this Visual visual, EnumerateTreeFilterCallback filterCallback, EnumerateTreeResultCallback enumeratorCallback, object misc)
{
if (visual == null)
{
throw new ArgumentNullException(nameof(visual));
}
DoEnumerateTree(visual, filterCallback, enumeratorCallback, misc);
}
public static void EnumerateTree(this Visual @this, EnumerateTreeFilterCallback filterCallback, EnumerateTreeResultCallback enumeratorCallback, object misc)
{
if (@this == null)
{
throw new ArgumentNullException("this");
}
DoEnumerateTree(@this, filterCallback, enumeratorCallback, misc);
}
