/// <summary>
/// Sets focus to the first focusable element in the details template
/// </summary>
private void FocusFirstFocusableElementInDetails()
{
if (GetTemplateChild(PartDetailsPanel) is DependencyObject details)
{
var focusableElement = FocusManager.FindFirstFocusableElement(details);
(focusableElement as Control)?.Focus(FocusState.Programmatic);
}
}
/// <summary>
/// Sets focus to the first focusable element in the details template
/// </summary>
private void FocusFirstFocusableElementInDetails()
{
if (GetTemplateChild(PART_DETAILS_PANE) is DependencyObject details)
{
DependencyObject focusableElement = FocusManager.FindFirstFocusableElement(details);
(focusableElement as Control)?.Focus(FocusState.Programmatic);
}
}
private async Task FocusPicker()
{
var element = FocusManager.FindFirstFocusableElement(_rootGrid);
if (element != null)
{
await FocusManager.TryFocusAsync(element, FocusState.Programmatic);
}
}
private void inputButton_KeyDown(object sender, KeyRoutedEventArgs e)
{
DependencyObject candidate;
if (e.Key == Windows.System.VirtualKey.Down)
{
e.Handled = true;
candidate = FocusManager.FindNextFocusableElement(FocusNavigationDirection.Down);
if (candidate != null)
{
(candidate as Control).Focus(FocusState.Keyboard);
}
else
{
candidate = FocusManager.FindFirstFocusableElement(candidate);
if (candidate != null)
{
(candidate as Control).Focus(FocusState.Keyboard);
}
}
}
else if (e.Key == Windows.System.VirtualKey.Up)
{
e.Handled = true;
candidate = FocusManager.FindNextFocusableElement(FocusNavigationDirection.Up);
if (candidate != null)
{
(candidate as Control).Focus(FocusState.Keyboard);
}
else
{
candidate = FocusManager.FindLastFocusableElement(candidate);
if (candidate != null)
{
(candidate as Control).Focus(FocusState.Keyboard);
}
}
}
}
Control FindFocusCandidate(int clearedIndex, out UIElement focusedChild)
{
// Walk through all the children and find elements with index before and after the cleared index.
// Note that during a delete the next element would now have the same index.
int previousIndex = int.MinValue;
int nextIndex = int.MaxValue;
UIElement nextElement = null;
UIElement previousElement = null;
var children = m_owner.Children;
for (int i = 0; i < children.Count; ++i)
{
var child = children[i];
var virtInfo = ItemsRepeater.TryGetVirtualizationInfo(child);
if (virtInfo != null && virtInfo.IsHeldByLayout)
{
int currentIndex = virtInfo.Index;
if (currentIndex < clearedIndex)
{
if (currentIndex > previousIndex)
{
previousIndex = currentIndex;
previousElement = child;
}
}
else if (currentIndex >= clearedIndex)
{
// Note that we use >= above because if we deleted the focused element,
// the next element would have the same index now.
if (currentIndex < nextIndex)
{
nextIndex = currentIndex;
nextElement = child;
}
}
}
}
// Find the next element if one exists, if not use the previous element.
// If the container itself is not focusable, find a descendent that is.
Control focusCandidate = null;
focusedChild = null;
if (nextElement != null)
{
focusedChild = nextElement as UIElement;
focusCandidate = nextElement as Control;
if (focusCandidate == null)
{
var firstFocus = FocusManager.FindFirstFocusableElement(nextElement);
if (firstFocus != null)
{
focusCandidate = firstFocus as Control;
}
}
}
if (focusCandidate == null && previousElement != null)
{
focusedChild = previousElement as UIElement;
focusCandidate = previousElement as Control;
if (previousElement == null)
{
var lastFocus = FocusManager.FindLastFocusableElement(previousElement);
if (lastFocus != null)
{
focusCandidate = lastFocus as Control;
}
}
}
return(focusCandidate);
}
