private void OnManipulationDelta(ManipulationDeltaRoutedEventArgs e)
{
e.Handled = true;
try
{
float?factor = null;
var offsetX = startHorizontalOffset - e.Cumulative.Translation.X;
var offsetY = startVerticalOffset - e.Cumulative.Translation.Y;
var currentScale = e.Cumulative.Scale;
if (currentScale != 1F)
{
factor = startZoomFactor * currentScale;
offsetX = offsetX * currentScale + startPosition.X * (currentScale - 1F);
offsetY = offsetY * currentScale + startPosition.Y * (currentScale - 1F);
}
AssociatedViewer.ChangeView(offsetX, offsetY, factor);
}
catch (Exception ex)
{
Debug.WriteLine($"Failed to reflect changes of ManipulationDalta.\r\n{ex}");
}
}
private void RestoreInViewerPosition(Point inViewerPosition, Point inSelectorPosition, float viewerZoomFactor, bool checkesItemInViewport = false)
{
var offsetX = inSelectorPosition.X * viewerZoomFactor - inViewerPosition.X;
var offsetY = inSelectorPosition.Y * viewerZoomFactor - inViewerPosition.Y;
if (checkesItemInViewport)
{
var left = offsetX / viewerZoomFactor;
var right = left + AssociatedViewer.ActualWidth / viewerZoomFactor;
var top = offsetY / viewerZoomFactor;
var bottom = top + AssociatedViewer.ActualHeight / viewerZoomFactor;
var existsItemInViewport = AssociatedSelector.GetDescendantsOfType <SelectorItem>()
.Select(item => item.TransformToVisual(AssociatedSelector).TransformPoint(default(Point)))
.Any(position => (left < position.X) && (position.X < right) && (top < position.Y) && (position.Y < bottom));
if (!existsItemInViewport)
{
return;
}
}
try
{
AssociatedViewer.ChangeView(offsetX, offsetY, viewerZoomFactor);
}
catch (Exception ex)
{
Debug.WriteLine($"Failed to restore position and zoom factor.\r\n{ex}");
}
}
private void OnManipulationDelta(ManipulationDeltaRoutedEventArgs e)
{
e.Handled = true;
try
{
float?factor = null;
var offsetX = _startHorizontalOffset - e.Cumulative.Translation.X;
var offsetY = _startVerticalOffset - e.Cumulative.Translation.Y;
var currentScale = e.Cumulative.Scale;
if (currentScale != 1F)
{
factor = _startZoomFactor * currentScale;
offsetX = offsetX * currentScale + _startPosition.X * (currentScale - 1F);
offsetY = offsetY * currentScale + _startPosition.Y * (currentScale - 1F);
}
//Debug.WriteLine("OffsetX:{0} OffsetY:{1} factor:{2}", offsetX, offsetY, factor);
AssociatedViewer.ChangeView(offsetX, offsetY, factor);
}
catch (Exception ex)
{
Debug.WriteLine("Failed to reflect changes of ManipulationDalta. {0}", ex);
throw new Exception("Failed to reflect changes of ManipulationDelta.", ex);
}
}
private void OnPointerMoved(PointerRoutedEventArgs e)
{
e.Handled = true;
var position = e.GetCurrentPoint(AssociatedViewer).Position;
var offsetX = startHorizontalOffsetPosition - position.X;
var offsetY = startVerticalOffsetPosition - position.Y;
AssociatedViewer.ChangeView(offsetX, offsetY, null);
}
private void OnPointerMoved(PointerRoutedEventArgs e)
{
e.Handled = true;
var position = e.GetCurrentPoint(AssociatedViewer).Position;
var offsetX = _startHorizontalOffsetPosition - position.X;
var offsetY = _startverticalOffsetPosition - position.Y;
//Debug.WriteLine("OffsetX:{0} OffsetY:{1}", offsetX, offsetY);
AssociatedViewer.ChangeView(offsetX, offsetY, null);
}