[JavaScript知识库]如何复制NodeViewModel

if (contentContainer.RenderTransform is ScaleTransform)

{

GeneralTransform transform = this.TransformToDescendant(contentContainer);

return transform.TransformBounds(new Rect(0, 0, this.ActualWidth, this.ActualHeight));

}

上面这段代码是计算,如果粘贴的画布做了缩大发小之后需要确定鼠标的位置.

一、 public partial class NetworkView : IViewFor<NetworkViewModel>：

private void miCopy_Click(object sender, RoutedEventArgs e) { 
var item = sender as MenuItem; Point mousePos = Mouse.GetPosition(dragCanvas); 
this.ViewModel.CopyNodes = this.ViewModel.SelectedNodes.Items.ToArray(); 
Console.WriteLine(e); 
} 
private void miPaste_Click(object sender, RoutedEventArgs e) {
 Point mousePos = Mouse.GetPosition(dragCanvas); 
if (contentContainer.RenderTransform is ScaleTransform) { 
GeneralTransform transform = this.TransformToDescendant(contentContainer); 
mousePos= transform.Transform(mousePos);
 }

 this.ViewModel.PasteSelectedNodes(mousePos); 
}

二、<UserControl x:Class="NodeNetwork.Views.NetworkView"

<controls:DragCanvas Zoom="DragCanvas_OnZoom" x:Name="dragCanvas" MouseLeftButtonDown="OnClickCanvas" Background="Green"> 
<controls:DragCanvas.ContextMenu>
 <ContextMenu DataContext="{Binding ViewModel.NetworkViewModel}"> 
<MenuItem Header="复制" x:Name="miCopy" Click="miCopy_Click"> 
</MenuItem> <MenuItem Header="粘贴" x:Name="miPaste" Click="miPaste_Click"> 
</MenuItem> </ContextMenu>
 </controls:DragCanvas.ContextMenu>

三、public class MainViewModel : ReactiveObject

public MainViewModel(){
 //when copySelectedNodes is Inooked,

 NetworkViewModel.PasteSelectedNodes = new Action<Point>(f => {
 Point firstPosition = f; 
int i = 0; do { 
var copyNode = NetworkViewModel.CopyNodes[i];
 var nodeTemplate = ListViewModel.NodeTemplates.Items.FirstOrDefault(f => f.Instance.GetType() == copyNode.GetType());
 var node = nodeTemplate.Factory(); 
if (i == 0) {
 node.Position = f;
 firstPosition = copyNode.Position;
 } else { 
var newPositionX = copyNode.Position.X - firstPosition.X;

 var newPositionY = copyNode.Position.Y - firstPosition.Y; 
node.Position = new Point(f.X + newPositionX, f.Y + newPositionY); 
} NetworkViewModel.Nodes.Add(node);
 node.IsSelected = true; i++; 
} while (i<NetworkViewModel.CopyNodes.Length );
});

private NodeViewModel[] CopyNodes;