protected override void OnPreviewMouseDown(MouseButtonEventArgs e)
{
base.OnPreviewMouseDown(e);
//更新选择项。
var designer = DesignerCanvas.GetOwnerCanvas(this);
if (designer != null)
{
designer.HandleMouseSelection(this);
}
e.Handled = false;
}
private DesignerItemContainer[] GetSelectedContainers()
{
DesignerItemContainer[] selectedDesignerItems = null;
var designerItem = this.DataContext as DesignerItemContainer;
if (designerItem != null && designerItem.IsSelected)
{
var designer = DesignerCanvas.GetOwnerCanvas(designerItem);
if (designer != null)
{
// only resize DesignerItems
selectedDesignerItems = designer.SelectedItems.OfType <DesignerItemContainer>().ToArray();
}
}
return(selectedDesignerItems);
}
void DragThumb_DragDelta(object sender, DragDeltaEventArgs e)
{
var designerItem = DesignerItemContainer.GetItemContainer(this);
if (designerItem != null && designerItem.IsSelected)
{
var designer = DesignerCanvas.GetOwnerCanvas(designerItem);
if (designer != null)
{
//只移动 DesignerItem
var designerItems = designer.SelectedItems.OfType <DesignerItemContainer>();
//以下代码不知何意，暂留。
//double minLeft = double.MaxValue;
//double minTop = double.MaxValue;
//foreach (var item in designerItems)
//{
// double left = GetDouble(item, Canvas.LeftProperty);
// double top = GetDouble(item, Canvas.TopProperty);
// minLeft = Math.Min(left, minLeft);
// minTop = Math.Min(top, minTop);
//}
//double deltaHorizontal = Math.Max(-minLeft, e.HorizontalChange);
//double deltaVertical = Math.Max(-minTop, e.VerticalChange);
double deltaHorizontal = e.HorizontalChange;
double deltaVertical = e.VerticalChange;
foreach (var item in designerItems)
{
double left = GetDouble(item, Canvas.LeftProperty);
double top = GetDouble(item, Canvas.TopProperty);
Canvas.SetLeft(item, left + deltaHorizontal);
Canvas.SetTop(item, top + deltaVertical);
}
designer.InvalidateMeasure();
e.Handled = true;
}
}
}