private void ResizeSelectedShapes_Executed(DragDeltaThumbEvent e)
{
if (this.Parent != null)
{
this.Parent.ResizeSelectedShapes(e);
}
}
public void ResizeThumb_DragDelta(object sender, DragDeltaThumbEvent e)
{
if (this.mResizeSelectedShapes != null)
{
// Call the bound (ShapeSizeViewModel) to implement this change via (XAML) command binding
if (this.mResizeSelectedShapes.CanExecute(null))
{
this.mResizeSelectedShapes.Execute(e);
}
}
}
/// <summary>
/// The resize shape function resizes all currently selected
/// shapes in accordance to the delta contained in the supplied
/// <paramref name="e"/> parameter.
///
/// Method is based on resize method in
/// http://www.codeproject.com/Articles/23871/WPF-Diagram-Designer-Part-3
/// </summary>
/// <param name="e"></param>
void IShapeParent.ResizeSelectedShapes(DragDeltaThumbEvent e)
{
if (SelectedItem.Shapes.Count == 0)
{
return;
}
double minLeft = double.MaxValue;
double minTop = double.MaxValue;
double minDeltaHorizontal = double.MaxValue;
double minDeltaVertical = double.MaxValue;
double dragDeltaVertical, dragDeltaHorizontal;
// filter for those items that contain a height property and
// find the min of their min (Height, Width) properties
foreach (var item in this.SelectedItem.Shapes)
{
ShapeSizeViewModelBase shape = item as ShapeSizeViewModelBase;
if (shape == null) // filter for those items that have a height or width
{
continue;
}
minLeft = Math.Min(shape.Left, minLeft);
minTop = Math.Min(shape.Top, minTop);
minDeltaVertical = Math.Min(minDeltaVertical, shape.Height - shape.MinHeight);
minDeltaHorizontal = Math.Min(minDeltaHorizontal, shape.Width - shape.MinWidth);
}
// Resize currently selected items with regard to min height and width determined before
foreach (var item in this.SelectedItem.Shapes)
{
ShapeSizeViewModelBase shape = item as ShapeSizeViewModelBase;
if (shape == null) // filter for those items that have a height or width
{
continue;
}
switch (e.VerticalAlignment)
{
// Changing an element at its bottom changes the its height only
case VerticalAlignment.Bottom:
dragDeltaVertical = Math.Min(-e.VerticalChange, minDeltaVertical);
shape.Height = shape.Height - dragDeltaVertical;
break;
// Changing an element at its top changes the Y position and the height
case VerticalAlignment.Top:
dragDeltaVertical = Math.Min(Math.Max(-minTop, e.VerticalChange), minDeltaVertical);
shape.Top = shape.Top + dragDeltaVertical;
shape.Height = shape.Height - dragDeltaVertical;
break;
}
switch (e.HorizontalAlignment)
{
// Changing an element at its left side changes the x position and its width
case HorizontalAlignment.Left:
dragDeltaHorizontal = Math.Min(Math.Max(-minLeft, e.HorizontalChange), minDeltaHorizontal);
shape.Left = shape.Left + dragDeltaHorizontal;
shape.Width = shape.Width - dragDeltaHorizontal;
break;
// Changing an element at its right side changes the its width only
case HorizontalAlignment.Right:
dragDeltaHorizontal = Math.Min(-e.HorizontalChange, minDeltaHorizontal);
shape.Width = shape.Width - dragDeltaHorizontal;
break;
}
}
}