/// <summary>
/// Initializes dragging of a line segment.
/// </summary>
/// <seealso cref="AutoPosModeOnly"/>
/// <param name="e">The <see cref="T:System.Windows.Input.MouseButtonEventArgs"/> that contains the event data. This event data reports details about the mouse button that was pressed and the handled state.</param>
protected override void OnMouseDown(MouseButtonEventArgs e)
{
if (e.ChangedButton == MouseButton.Left && !AutoPosModeOnly)
{
segmentDragging = true;
dragLast = e.GetPosition(XCaseCanvas);
int i = JunctionGeometryHelper.FindHitSegmentIndex(dragLast, Points);
affectedPoints = new JunctionPoint[] { Points[i], Points[i + 1] };
startPositions = new Dictionary <DragThumb, rPoint>();
if (affectedPoints[0].Movable)
{
startPositions[affectedPoints[0]] = new rPoint(affectedPoints[0].Position)
{
tag = affectedPoints[0].Placement
}
}
;
if (affectedPoints[1].Movable)
{
startPositions[affectedPoints[1]] = new rPoint(affectedPoints[1].Position)
{
tag = affectedPoints[1].Placement
}
}
;
this.CaptureMouse();
}
base.OnMouseDown(e);
}
void viewHelperPointsCollection_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e is ObservablePointCollection.PointCollectionChangedEventArgs &&
((ObservablePointCollection.PointCollectionChangedEventArgs)e).PointPositionsMovedOnly)
{
for (int i = 0; i < viewHelperPointsCollection.Count; i++)
{
Point point = viewHelperPointsCollection[i];
Points[i].X = point.X;
Points[i].Y = point.Y;
}
}
else
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
if (e.NewItems.Count != 1)
{
throw new ArgumentOutOfRangeException("e", "Only one added point expected.");
}
BreakLine(viewHelperPointsCollection[e.NewStartingIndex], e.NewStartingIndex);
break;
case NotifyCollectionChangedAction.Remove:
if (e.OldItems.Count != 1)
{
throw new ArgumentOutOfRangeException("e", "Only one removed point expected.");
}
StraightenLine(e.OldStartingIndex);
break;
case NotifyCollectionChangedAction.Replace:
if (e.NewItems.Count != 1)
{
throw new ArgumentOutOfRangeException("e", "Only one replaced point expected.");
}
rPoint newPoint = (rPoint)e.NewItems[0];
if (newPoint.tag is EPlacementKind)
{
Points[e.NewStartingIndex].Placement = (EPlacementKind)newPoint.tag;
}
viewHelperPointsCollection[e.NewStartingIndex].Set(newPoint);
break;
case NotifyCollectionChangedAction.Reset:
break;
default:
throw new ArgumentOutOfRangeException("e", "Unknown action.");
}
}
}
