HOW TO：攔截圖案或 Decorator 上的點選

發行項
02/22/2013

下列程序將示範如何攔截中的，按一下 [在圖形或圖示裝飾。您可以攔截按一下、按兩下、拖曳和其他筆勢，以回應的項目。

在圖形上的截距按鍵動作

在 Dsl 專案中，產生的程式碼檔案中，不同的程式碼檔中寫入 shape 類別的部分類別定義。覆寫OnDoubleClick()或具有名稱開頭的方法之一來On...。例如：

public partial class MyShape // change
  {
    public override void OnDoubleClick(DiagramPointEventArgs e)
    {
      base.OnDoubleClick(e);
      System.Windows.Forms.MessageBox.Show("Click");
      e.Handled = true;
  }  }

注意事項
設定e.Handled到true，除非您想要傳遞至包含圖形或圖表的事件。

在 [裝飾的截距按鍵動作

影像裝飾都會有的 OnDoubleClick 方法的 ImageField 類別的執行個體上執行。如果您撰寫的 ImageField 子類別，您可以攔截按下滑鼠。欄位會設定在 InitializeShapeFields 方法中。因此，您必須變更您的子類別，而非一般的 ImageField 具現化該方法。 InitializeShapeFields 方法是在產生的程式碼的 shape 類別。如果您設定，您可以覆寫 shape 類別及其Generates Double Derived屬性，如下列程序所述。

雖然 InitializeShapeFields 執行個體方法，它會呼叫一次每個類別。因此，每個類別，每個圖案在圖表中不包含一個執行個體中每個欄位具有 ClickableImageField 只能有一個執行個體。當使用者按兩下執行個體時，您必須識別被叫用哪一個執行個體，如範例所示的程式碼所示。

若要攔截中的，按一下 [圖示裝飾

開啟或建立一個 DSL 的解決方案。
選擇或建立的圖形圖示裝飾，並將它對應至網域類別。

程式碼檔案中的檔案與不同GeneratedCode資料夾中，建立新的子類別的 ImageField：

using Microsoft.VisualStudio.Modeling;
using Microsoft.VisualStudio.Modeling.Design;
using Microsoft.VisualStudio.Modeling.Diagrams;
using System.Collections.Generic;
using System.Linq;

namespace Fabrikam.MyDsl { // Change to your namespace
internal class ClickableImageField : ImageField
{
  // You can also override OnClick and so on.
  public override void OnDoubleClick(DiagramPointEventArgs e)
  {
    base.OnDoubleClick(e);
    // Work out which instance was hit.
    MyShape shapeHit = e.HitDiagramItem.Shape as MyShape;
    if (shapeHit != null)
    {
      MyDomainClass element = 
          shapeHit.ModelElement as MyDomainClass;
      System.Windows.Forms.MessageBox.Show(
         "Double click on shape for " + element.Name);
      // If we do not set Handled, the event will
      // be passed to the containing shape:
      e.Handled = true;
    }
  }

   public ClickableImageField(string fieldName)
     : base(fieldName)
   { }
}

您應該設定為 true，如果您不想要傳遞至包含圖形事件 Handled。

藉由新增下列的部分類別定義會覆寫您的圖形 classs 的 InitializeShapeFields 方法。

public partial class MyShape // change
{
 protected override void InitializeShapeFields
      (IList<ShapeField> shapeFields)
 {
  base.InitializeShapeFields(shapeFields);
  // You can see the above method in MyShapeBase 
  // in the generated Shapes.cs
  // It has already added fields for the Icons.
  // So you will have to retrieve them and replace with your own.
  ShapeField unwantedField = shapeFields.First
      (field => field.Name == "IconDecorator1");
  shapeFields.Remove(unwantedField);

  // Now replicate the generated code from the base class 
  // in Shape.cs, but with your own image constructor.
  ImageField field2 = new ClickableImageField("IconDecorator1");      
  field2.DefaultImage = ImageHelper.GetImage(
    MyDslDomainModel.SingletonResourceManager
    .GetObject("MyShapeIconDecorator1DefaultImage"));
      shapeFields.Add(field2);
}

建置並執行方案。
連按兩下圖案的執行個體上的圖示。您的測試訊息應該會出現。

攔截按一下並拖曳 CompartmentShape 清單

下列範例允洏峈各區間圖案中的項目重新排序拖放。若要執行這段程式碼：

藉由建立新的 DSL 方案類別圖表方案範本。

您也可以使用您自己的方案包含文件圖案區間。這段程式碼會假設為內嵌的關聯性的圖案所代表的模型項目和表示分隔的清單項目中的項目之間。
設定會產生雙衍生的區間圖案的屬性。
在檔案中加入下列程式碼Dsl專案。
調整網域類別和圖形名稱，在這段程式碼，以符合您的 DSL。

總之，程式碼如下所示。在這個範例中， ClassShape區間圖案的名稱。

滑鼠事件處理常式的一組附加至每一個區間的執行個體建立時。
ClassShape.MouseDown事件會儲存目前的項目。
當滑鼠移出目前的項目，建立 MouseAction 的執行個體時，可設定的游標和捕捉到滑鼠，直到釋放它為止。

若要避免干擾其他的滑鼠動作，例如選取文字的項目，直到滑鼠離開了原始的項目，不會建立 MouseAction。

建立 MouseAction 的替代方式是只接聽 MouseUp。不過，這會無法正常運作如果使用者釋放滑鼠按鈕之後將它拖曳外區間。 MouseAction 都能執行適當的動作，則不論放開滑鼠時。
當使用者放開滑鼠時，MouseAction.MouseUp 會重新排列模型元素之間的連結的順序。
角色順序的變更就會引發的規則，以更新顯示畫面。這種行為已經被定義，並沒有額外的程式碼是必要的。

using Microsoft.VisualStudio.Modeling;
using Microsoft.VisualStudio.Modeling.Design;
using Microsoft.VisualStudio.Modeling.Diagrams;
using System.Collections.Generic;
using System.Linq;

// This sample allows users to re-order items in a compartment shape by dragging.

// This example is built on the "Class Diagrams" solution template of VMSDK (DSL Tools).
// You will need to change the following domain class names to your own:
// ClassShape = a compartment shape
// ClassModelElement = the domain class displayed using a ClassShape
// This code assumes that the embedding relationships 
// displayed in the compartments don't use inheritance 
// (don't have base or derived domain relationships).

namespace Company.CompartmentDrag
{
 /// <summary>
 /// Manage the mouse while dragging a compartment item.
 /// </summary>
 public class CompartmentDragMouseAction : MouseAction
 {
  private ModelElement sourceChild;
  private ClassShape sourceShape;
  private RectangleD sourceCompartmentBounds;

  public CompartmentDragMouseAction(ModelElement sourceChildElement, ClassShape sourceParentShape, RectangleD bounds)
   : base (sourceParentShape.Diagram)
  {
   sourceChild = sourceChildElement;
   sourceShape = sourceParentShape;
   sourceCompartmentBounds = bounds; // For cursor.
  }
   
  /// <summary>
  /// Call back to the source shape to drop the dragged item.
  /// </summary>
  /// <param name="e"></param>
  protected override void OnMouseUp(DiagramMouseEventArgs e)
  {
   base.OnMouseUp(e);
   sourceShape.DoMouseUp(sourceChild, e);
   this.Cancel(e.DiagramClientView);
   e.Handled = true;
  }

  /// <summary>
  /// Ideally, this shouldn't happen. This action should only be active
  /// while the mouse is still pressed. However, it can happen if you
  /// move the mouse rapidly out of the source shape, let go, and then 
  /// click somewhere else in the source shape.
  /// </summary>
  /// <param name="e"></param>
  protected override void OnMouseDown(DiagramMouseEventArgs e)
  {
   base.OnMouseDown(e);
   this.Cancel(e.DiagramClientView);
   e.Handled = false;
  }

  /// <summary>
  /// Display an appropriate cursor while the drag is in progress:
  /// Up-down arrow if we are inside the original compartment.
  /// No entry if we are elsewhere.
  /// </summary>
  /// <param name="currentCursor"></param>
  /// <param name="diagramClientView"></param>
  /// <param name="mousePosition"></param>
  /// <returns></returns>
  public override System.Windows.Forms.Cursor GetCursor(System.Windows.Forms.Cursor currentCursor, DiagramClientView diagramClientView, PointD mousePosition)
  {
   // If the cursor is inside the original compartment, show up-down cursor.
   return sourceCompartmentBounds.Contains(mousePosition) 
    ? System.Windows.Forms.Cursors.SizeNS // Up-down arrow.
    : System.Windows.Forms.Cursors.No;
  }
 }

 /// <summary>
 /// Override some methods of the compartment shape.
 /// *** GenerateDoubleDerived must be set for this shape in DslDefinition.dsl. ****
 /// </summary>
 public partial class ClassShape
 {
  /// <summary>
  /// Model element that is being dragged.
  /// </summary>
  private static ClassModelElement dragStartElement = null;
  /// <summary>
  /// Absolute bounds of the compartment, used to set the cursor.
  /// </summary>
  private static RectangleD compartmentBounds;

  /// <summary>
  /// Attach mouse listeners to the compartments for the shape.
  /// This is called once per compartment shape.
  /// The base method creates the compartments for this shape.
  /// </summary>
  public override void EnsureCompartments()
  {
   base.EnsureCompartments();
   foreach (Compartment compartment in this.NestedChildShapes.OfType<Compartment>())
   {
    compartment.MouseDown += new DiagramMouseEventHandler(compartment_MouseDown);
    compartment.MouseUp += new DiagramMouseEventHandler(compartment_MouseUp);
    compartment.MouseMove += new DiagramMouseEventHandler(compartment_MouseMove);
   }
  }


  /// <summary>
  /// Remember which item the mouse was dragged from.
  /// We don't create an Action immediately, as this would inhibit the
  /// inline text editing feature. Instead, we just remember the details
  /// and will create an Action when/if the mouse moves off this list item.
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  void compartment_MouseDown(object sender, DiagramMouseEventArgs e)
  {
   dragStartElement = e.HitDiagramItem.RepresentedElements
     .OfType<ClassModelElement>().FirstOrDefault();
   compartmentBounds = e.HitDiagramItem.Shape.AbsoluteBoundingBox;
  }

  /// <summary>
  /// When the mouse moves away from the initial list item,
  /// but still inside the compartment, create an Action 
  /// to supervise the cursor and handle subsequent mouse events.
  /// Transfer the details of the initial mouse position to the Action.
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  void compartment_MouseMove(object sender, DiagramMouseEventArgs e)
  {
   if (dragStartElement != null)
   {
    if (dragStartElement != e.HitDiagramItem.RepresentedElements.OfType<ClassModelElement>().FirstOrDefault())
    {
     e.DiagramClientView.ActiveMouseAction = new CompartmentDragMouseAction(dragStartElement, this, compartmentBounds);
     dragStartElement = null;
    }
   }
  }

  /// <summary>
  /// User has released the mouse button. 
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  void compartment_MouseUp(object sender, DiagramMouseEventArgs e)
  {
    dragStartElement = null;
  }

  /// <summary>
  /// Forget the source item if mouse up occurs outside the
  /// compartment.
  /// </summary>
  /// <param name="e"></param>
  public override void OnMouseUp(DiagramMouseEventArgs e)
  {
   base.OnMouseUp(e);
   dragStartElement = null;
  }


  /// <summary>
  /// Called by the Action when the user releases the mouse.
  /// If we are still on the same compartment but in a different list item,
  /// move the starting item to the position of the current one.
  /// </summary>
  /// <param name="dragFrom"></param>
  /// <param name="e"></param>
  public void DoMouseUp(ModelElement dragFrom, DiagramMouseEventArgs e)
  {
   // Original or "from" item:
   ClassModelElement dragFromElement = dragFrom as ClassModelElement;
   // Current or "to" item:
   ClassModelElement dragToElement = e.HitDiagramItem.RepresentedElements.OfType<ClassModelElement>().FirstOrDefault();
   if (dragFromElement != null && dragToElement != null)
   {
    // Find the common parent model element, and the relationship links:
    ElementLink parentToLink = GetEmbeddingLink(dragToElement);
    ElementLink parentFromLink = GetEmbeddingLink(dragFromElement);
    if (parentToLink != parentFromLink && parentFromLink != null && parentToLink != null)
    {
     // Get the static relationship and role (= end of relationship):
     DomainRelationshipInfo relationshipFrom = parentFromLink.GetDomainRelationship();
     DomainRoleInfo parentFromRole = relationshipFrom.DomainRoles[0];
     // Get the node in which the element is embedded, usually the element displayed in the shape:
     ModelElement parentFrom = parentFromLink.LinkedElements[0];

     // Same again for the target:
     DomainRelationshipInfo relationshipTo = parentToLink.GetDomainRelationship();
     DomainRoleInfo parentToRole = relationshipTo.DomainRoles[0];
     ModelElement parentTo = parentToLink.LinkedElements[0];

     // Mouse went down and up in same parent and same compartment:
     if (parentTo == parentFrom && relationshipTo == relationshipFrom)
     {
      // Find index of target position:
      int newIndex = 0;
      var elementLinks = parentToRole.GetElementLinks(parentTo);
      foreach (ElementLink link in elementLinks)
      {
       if (link == parentToLink) { break; }
       newIndex++;
      }

      if (newIndex < elementLinks.Count)
      {
       using (Transaction t = parentFrom.Store.TransactionManager.BeginTransaction("Move list item"))
       {
        parentFromLink.MoveToIndex(parentFromRole, newIndex);
        t.Commit();
       }
      }
     }
    }
   }
  }

  /// <summary>
  /// Get the embedding link to this element.
  /// Assumes there is no inheritance between embedding relationships.
  /// (If there is, you need to make sure you've got the relationship
  /// that is represented in the shape compartment.)
  /// </summary>
  /// <param name="child"></param>
  /// <returns></returns>
  ElementLink GetEmbeddingLink(ClassModelElement child)
  {
   foreach (DomainRoleInfo role in child.GetDomainClass().AllEmbeddedByDomainRoles)
   {
    foreach (ElementLink link in role.OppositeDomainRole.GetElementLinks(child))
    {
     // Just the assume the first embedding link is the only one.
     // Not a valid assumption if one relationship is derived from another.
     return link;
    }
   }
   return null;
  }
 }
}

共用方式為