private void OnDragDelta(object sender, DragDeltaEventArgs e)
{
var block = DataContext as BlockViewModel;
var diagram = VisualTreeHelper.GetParent(block) as DiagramCanvas;
if (block != null && diagram != null && block.IsSelected)
{
double minLeft = double.MaxValue;
double minTop = double.MaxValue;
// only move blocks
var blocks = from element in diagram.SelectedElements
where element is BlockViewModel
select element;
// Sets left and top position
foreach (BlockViewModel element in blocks)
{
var left = Canvas.GetLeft(element);
var top = Canvas.GetTop(element);
minLeft = double.IsNaN(left) ? 0 : Math.Min(left, minLeft);
minTop = double.IsNaN(top) ? 0 : Math.Min(top, minTop);
}
// Calculate delta movement
var deltaHorizontal = Math.Max(-minLeft, e.HorizontalChange);
var deltaVertical = Math.Max(-minTop, e.VerticalChange);
// Set moved postion
foreach (BlockViewModel element in blocks)
{
var left = Canvas.GetLeft(element);
var top = Canvas.GetTop(element);
if (double.IsNaN(left))
{
left = 0;
}
if (double.IsNaN(top))
{
top = 0;
}
element.BlockModel.Position = new Point(left + deltaHorizontal, top + deltaVertical);
DiagramCanvas.UpdatePosition(element);
}
diagram.InvalidateMeasure();
e.Handled = true;
}
}
private void OnModelChanged(object sender, PropertyChangedEventArgs e)
{
if (e.PropertyName == "Height")
{
Height = blockModel.Height;
}
if (e.PropertyName == "Width")
{
Width = blockModel.Width;
}
DiagramCanvas.UpdatePosition(this);
}