private static IInputElement?GetPrevTabWithSameIndex(IInputElement e, IInputElement container)
{
int elementTabPriority = KeyboardNavigation.GetTabIndex(e);
var currElement = GetPreviousInTree(e, container);
while (currElement != null)
{
if (IsTabStopOrGroup(currElement) && KeyboardNavigation.GetTabIndex(currElement) == elementTabPriority && currElement != container)
{
return(currElement);
}
currElement = GetPreviousInTree(currElement, container);
}
return(null);
}
private static IInputElement?GetNextTabWithSameIndex(IInputElement e, IInputElement container)
{
var elementTabPriority = KeyboardNavigation.GetTabIndex(e);
var currElement = e;
while ((currElement = GetNextInTree(currElement, container)) != null)
{
if (IsTabStopOrGroup(currElement) && KeyboardNavigation.GetTabIndex(currElement) == elementTabPriority)
{
return(currElement);
}
}
return(null);
}
private static IInputElement?GetPrevTabWithPrevIndex(IInputElement e, IInputElement container, KeyboardNavigationMode tabbingType)
{
// Find the next max index in the tree
// max (index<currentTabIndex)
IInputElement?lastTabElement = null;
IInputElement?nextTabElement = null;
int elementTabPriority = KeyboardNavigation.GetTabIndex(e);
int maxIndexFirstTab = Int32.MaxValue;
int maxIndex = Int32.MaxValue;
var currElement = GetLastInTree(container);
while (currElement != null)
{
if (IsTabStopOrGroup(currElement) && currElement != container)
{
int currPriority = KeyboardNavigation.GetTabIndex(currElement);
if (currPriority < elementTabPriority)
{
if (currPriority > maxIndex || nextTabElement == null)
{
maxIndex = currPriority;
nextTabElement = currElement;
}
}
if (currPriority > maxIndexFirstTab || lastTabElement == null)
{
maxIndexFirstTab = currPriority;
lastTabElement = currElement;
}
}
currElement = GetPreviousInTree(currElement, container);
}
// Cycle groups: if not found - return first element
if (tabbingType == KeyboardNavigationMode.Cycle && nextTabElement == null)
{
nextTabElement = lastTabElement;
}
return(nextTabElement);
}
private static IInputElement?GetNextTabWithNextIndex(IInputElement e, IInputElement container, KeyboardNavigationMode tabbingType)
{
// Find the next min index in the tree
// min (index>currentTabIndex)
IInputElement?nextTabElement = null;
IInputElement?firstTabElement = null;
int minIndexFirstTab = int.MinValue;
int minIndex = int.MinValue;
int elementTabPriority = KeyboardNavigation.GetTabIndex(e);
IInputElement?currElement = container;
while ((currElement = GetNextInTree(currElement, container)) != null)
{
if (IsTabStopOrGroup(currElement))
{
int currPriority = KeyboardNavigation.GetTabIndex(currElement);
if (currPriority > elementTabPriority)
{
if (currPriority < minIndex || nextTabElement == null)
{
minIndex = currPriority;
nextTabElement = currElement;
}
}
if (currPriority < minIndexFirstTab || firstTabElement == null)
{
minIndexFirstTab = currPriority;
firstTabElement = currElement;
}
}
}
// Cycle groups: if not found - return first element
if (tabbingType == KeyboardNavigationMode.Cycle && nextTabElement == null)
{
nextTabElement = firstTabElement;
}
return(nextTabElement);
}
private static IInputElement?GetLastTabInGroup(IInputElement container)
{
IInputElement?lastTabElement = null;
int maxIndexFirstTab = int.MaxValue;
var currElement = GetLastInTree(container);
while (currElement != null && currElement != container)
{
if (IsTabStopOrGroup(currElement))
{
int currPriority = KeyboardNavigation.GetTabIndex(currElement);
if (currPriority > maxIndexFirstTab || lastTabElement == null)
{
maxIndexFirstTab = currPriority;
lastTabElement = currElement;
}
}
currElement = GetPreviousInTree(currElement, container);
}
return(lastTabElement);
}
private static IInputElement?GetFirstTabInGroup(IInputElement container)
{
IInputElement?firstTabElement = null;
int minIndexFirstTab = int.MinValue;
var currElement = container;
while ((currElement = GetNextInTree(currElement, container)) != null)
{
if (IsTabStopOrGroup(currElement))
{
int currPriority = KeyboardNavigation.GetTabIndex(currElement);
if (currPriority < minIndexFirstTab || firstTabElement == null)
{
minIndexFirstTab = currPriority;
firstTabElement = currElement;
}
}
}
return(firstTabElement);
}