void OnScrollAreaDragging(Point newDraggingPoint)
{
if (IsDragging == false)
{
return;
}
DraggingPoint = newDraggingPoint;
refToViewModel.DraggingPoint = DraggingPoint;
var deltaPointForScrollToHorizontalOffset = DraggingPoint - DraggingPointPreviousForScrollToHorizontalOffset;
ContentHorizontalOffsetDesired += deltaPointForScrollToHorizontalOffset.X;
ScrollAreaScrollViewer.ScrollToHorizontalOffset(-ContentHorizontalOffsetDesired);
DraggingPointPreviousForScrollToHorizontalOffset = DraggingPoint;
UpdateDraggingVelocity();
}
void OnScrollAreaDispatcherTimerUpdateScrolling()
{
if (IsDragging)
{
UpdateDraggingVelocity();
}
else
{
FlickingCursorVelocity = FlickingCursorVelocityEmaAlphaInDeltaTime * FlickingCursorVelocity;
ContentHorizontalOffsetDesired += FlickingCursorVelocity.X * TimerIntervalTotalSeconds;
ScrollAreaScrollViewer.ScrollToHorizontalOffset(-ContentHorizontalOffsetDesired);
if (Math.Abs(FlickingCursorVelocity.X) < 1e-5)
{
DragVelocityEstimationAndFlickScrollingDispatcherTimer.Stop();
}
}
}
void InitializeScrollArea()
{
DragVelocityEstimationAndFlickScrollingDispatcherTimer.Interval = TimeSpan.FromSeconds(TimerIntervalTotalSeconds);
UpdateFlickingCursorVelocityEmaAlphaInDeltaTime();
ScrollAreaListView.SizeChanged += (sender, e) =>
{
ContentHorizontalOffsetDesired = -ScrollAreaListView.ActualWidth / 2;
ScrollAreaScrollViewer.ScrollToHorizontalOffset(-ContentHorizontalOffsetDesired);
};
// TODO: In Windows 7, flick gesture is unavailable in the first execution of this application.
if (ApplicationCommonSettings.IsToEmulateReportByActualMouseRawInputToDebugViews)
{
ScrollAreaListView.MouseLeftButtonDown += (sender, e) => { OnScrollAreaDragStarted(e.GetPosition(ScrollAreaScrollViewer)); };
ScrollAreaListView.MouseMove += (sender, e) => { OnScrollAreaDragging(e.GetPosition(ScrollAreaScrollViewer)); };
ScrollAreaListView.MouseLeftButtonUp += (sender, e) => { if (IsDragging)
{
OnScrollAreaDragEndedFlickStarted();
}
};
ScrollAreaListView.MouseLeave += (sender, e) => { if (IsDragging)
{
OnScrollAreaDragEndedFlickStarted();
}
};
}
else
{
ScrollAreaListView.TouchDown += (sender, e) => { OnScrollAreaDragStarted(e.GetTouchPoint(ScrollAreaScrollViewer).Position); };
ScrollAreaListView.TouchMove += (sender, e) => { OnScrollAreaDragging(e.GetTouchPoint(ScrollAreaScrollViewer).Position); };
ScrollAreaListView.TouchUp += (sender, e) => { if (IsDragging)
{
OnScrollAreaDragEndedFlickStarted();
}
};
ScrollAreaListView.TouchLeave += (sender, e) => { if (IsDragging)
{
OnScrollAreaDragEndedFlickStarted();
}
};
}
if (false)
{
if (false)
{
ScrollAreaListView.ManipulationStarted += delegate { Debug.WriteLine("ManipulationStarted"); };
ScrollAreaListView.ManipulationDelta += delegate { Debug.WriteLine("ManipulationDelta"); };
ScrollAreaListView.ManipulationInertiaStarting += delegate { Debug.WriteLine("ManipulationInertiaStarting"); };
}
ScrollAreaListView.ManipulationStarted += (sender, e) => { OnScrollAreaDragStarted(e.ManipulationOrigin); };
ScrollAreaListView.ManipulationDelta += (sender, e) => { OnScrollAreaDragging(e.ManipulationOrigin); };
ScrollAreaListView.ManipulationInertiaStarting += (sender, e) => { if (IsDragging)
{
OnScrollAreaDragEndedFlickStarted();
}
};
}
DragVelocityEstimationAndFlickScrollingDispatcherTimer.Tick += (sender, e) => { OnScrollAreaDispatcherTimerUpdateScrolling(); };
}