/// <summary>
/// Retrieves the visible containers in a LongListSelector and adds them to <paramref name="items"/>.
/// </summary>
/// <param name="list">LongListSelector that contains the items.</param>
/// <param name="itemsPanel">Direct parent of the items.</param>
/// <param name="items">List to populate with the containers currently in the viewport</param>
/// <param name="selectContent">
/// Specifies whether to return the container or its content.
/// For headers, we can't apply projections on the container directly (or everything will go blank),
/// so we will apply them on the content instead.
/// </param>
private static void AddVisibileContainers(LongListSelector list, Canvas itemsPanel, List <KeyValuePair <double, FrameworkElement> > items, bool selectContent)
{
foreach (DependencyObject obj in VisualTreeExtensions.GetVisualChildren(itemsPanel))
{
ContentPresenter container = obj as ContentPresenter;
if (container != null &&
(!selectContent ||
(VisualTreeHelper.GetChildrenCount(container) == 1 &&
VisualTreeHelper.GetChild(container, 0) is FrameworkElement)))
{
GeneralTransform itemTransform = null;
try
{
itemTransform = container.TransformToVisual(list);
}
catch (ArgumentException)
{
// Ignore failures when not in the visual tree
break;
}
Rect boundingBox = new Rect(itemTransform.Transform(new Point()), itemTransform.Transform(new Point(container.ActualWidth, container.ActualHeight)));
if (boundingBox.Bottom > 0 && boundingBox.Top < list.ActualHeight)
{
items.Add(
new KeyValuePair <double, FrameworkElement>(
boundingBox.Top,
selectContent
? (FrameworkElement)VisualTreeHelper.GetChild(container, 0)
: container));
}
}
}
}
/// <summary>
/// Helper function to see if any portion of the given frame is on screen.
/// </summary>
/// <param name="viewport">Where the viewport currently exists, in teh child's coordinates</param>
/// <param name="content">The UI element of the thing we are trying to see if is in view.</param>
/// <returns>True if the content is in the view port of the scroll bar.</returns>
private bool isInFrame(Rect viewport, ContentPresenter content)
{
var transform = content.TransformToVisual(_itemContainer);
var childBounds = transform.TransformBounds(new Rect(new Point(0, 0), content.RenderSize));
childBounds.Intersect(viewport);
return(!childBounds.IsEmpty);
}
/// <summary>
/// Get the current visual bounds of the content.
/// </summary>
/// <returns>The current visual bounds of the content</returns>
private Rect GetContentBounds()
{
Rect bounds = VisualTreeHelper.GetDescendantBounds(_content);
GeneralTransform generalTransform = _content.TransformToVisual(this);
Point topLeft = generalTransform.Transform(bounds.TopLeft);
Point bottomRight = generalTransform.Transform(bounds.BottomRight);
return(new Rect(topLeft, bottomRight));
}
private async Task RecognizeInkerText()
{
try
{
var inkRecognizer = new InkRecognizerContainer();
var recognitionResults = await inkRecognizer.RecognizeAsync(_inker.InkPresenter.StrokeContainer, InkRecognitionTarget.All);
List <TextBox> boxes = new List <TextBox>();
var ttv = _contentPresenter.TransformToVisual(Window.Current.Content);
Point offsetCoords = ttv.TransformPoint(new Point(0, 0));
foreach (var result in recognitionResults)
{
List <UIElement> elements = new List <UIElement>(
VisualTreeHelper.FindElementsInHostCoordinates(
new Rect(
new Point(
result.BoundingRect.X + offsetCoords.X,
result.BoundingRect.Y + offsetCoords.Y),
new Size(result.BoundingRect.Width, result.BoundingRect.Height)),
_contentPresenter));
// find one with overlap
var textBoxes = elements.Where(el => el is TextBox && (el as TextBox).IsEnabled);
var maxOverlapArea = 0d;
TextBox box = null;
foreach (var textBox in textBoxes)
{
var bounds = textBox.TransformToVisual(_contentPresenter).TransformBounds(new Rect(0, 0, textBox.RenderSize.Width, textBox.RenderSize.Height));
var xOverlap = Math.Max(0, Math.Min(result.BoundingRect.Right, bounds.Right) - Math.Max(result.BoundingRect.Left, bounds.Left));
var yOverlap = Math.Max(0, Math.Min(result.BoundingRect.Bottom, bounds.Bottom) - Math.Max(result.BoundingRect.Top, bounds.Top));
var overlapArea = xOverlap * yOverlap;
if (overlapArea > maxOverlapArea)
{
maxOverlapArea = overlapArea;
box = textBox as TextBox;
}
}
//TextBox box = elements.Where(el => el is TextBox && (el as TextBox).IsEnabled).FirstOrDefault() as TextBox;
if (box != null)
{
var text = result.GetTextCandidates().FirstOrDefault().Trim();
if (!boxes.Contains(box))
{
boxes.Add(box);
box.Text = text;
}
else
{
box.Text += " " + text;
}
}
}
}
catch (Exception ex)
{
if (Debugger.IsAttached)
{
Debugger.Break();
}
}
finally
{
_inker.InkPresenter.StrokeContainer.Clear();
}
}