private void Thumb_DragDelta(object sender, DragDeltaEventArgs e)
{
GanttChartView ganttChartView;
ScrollViewer scrollViewer;
GanttChartItem dataContext = this.Thumb.DataContext as GanttChartItem;
if (dataContext != null)
{
ganttChartView = dataContext.GanttChartView as GanttChartView;
if ((ganttChartView != null) && !dataContext.HasChildren)
{
this.horizontalChange = e.HorizontalChange;
scrollViewer = ganttChartView.ScrollViewer;
if (!this.isDuringInternalScrollOperation)
{
double x = this.originalHorizontalPosition + this.horizontalChange;
double itemHeight = ganttChartView.ItemHeight;
Point p = new Point(x, 0.0);
this.isDuringInternalScrollOperation = true;
base.Dispatcher.BeginInvoke((Action)(() =>
{
double previousHorizontalOffset = scrollViewer.HorizontalOffset;
ScrollContentPresenter visual = ganttChartView.ScrollContentPresenter;
if ((scrollViewer != null) && (visual != null))
{
try
{
p = this.TransformToVisual(visual).Transform(p);
if (p.X < itemHeight)
{
scrollViewer.ScrollToHorizontalOffset(scrollViewer.HorizontalOffset - itemHeight);
}
if (p.X > (scrollViewer.ViewportWidth - itemHeight))
{
scrollViewer.ScrollToHorizontalOffset(scrollViewer.HorizontalOffset + itemHeight);
}
}
catch
{
}
}
this.Dispatcher.BeginInvoke((Action)(() =>
{
this.originalHorizontalPosition -= scrollViewer.HorizontalOffset - previousHorizontalOffset;
this.isDuringInternalScrollOperation = false;
}));
}));
}
switch (this.Role)
{
case DragTaskThumbRole.UpdateFinish:
if (!dataContext.IsMilestone)
{
double num3 = ganttChartView.GetPosition(dataContext.Finish) + e.HorizontalChange;
dataContext.Finish = ganttChartView.GetPreviousVisibleWorkingTime(ganttChartView.GetUpdateScaleTime(ganttChartView.GetDateTime(num3)));
return;
}
return;
case DragTaskThumbRole.UpdateCompletedFinish:
if (!dataContext.IsMilestone)
{
double num4 = ganttChartView.GetPosition(dataContext.CompletedFinish) + e.HorizontalChange;
dataContext.CompletedFinish = ganttChartView.GetPreviousVisibleWorkingTime(ganttChartView.GetUpdateScaleTime(ganttChartView.GetDateTime(num4)));
return;
}
return;
}
double position = ganttChartView.GetPosition(dataContext.Start) + e.HorizontalChange;
TimeSpan effort = dataContext.Effort;
TimeSpan completedEffort = dataContext.CompletedEffort;
dataContext.Start = ganttChartView.GetNextVisibleWorkingTime(ganttChartView.GetUpdateScaleTime(ganttChartView.GetDateTime(position)));
if (!dataContext.IsMilestone)
{
dataContext.Effort = effort;
dataContext.CompletedEffort = completedEffort;
}
}
}
}
