CanGroup Property

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public virtual bool CanGroup {get;}

'Declaration
 
Public Overridable ReadOnly Property CanGroup As Boolean

'Usage
 
Dim instance As AnnAutomation
Dim value As Boolean
 
value = instance.CanGroup

public virtual bool CanGroup {get;}

 get_CanGroup();

public:
virtual property bool CanGroup {
   bool get();
}

Property Value

true if this AnnAutomation is in a state where objects can be grouped together; false otherwise.

The AnnAutomation is in a state where objects can be grouped together when 2 or more objects are in an edit state.

Call the Group method to group the objects currently being edited together.

Note, when you select one or more objects in this AnnAutomation through the user interface, an AnnGroupObject will be created and the selected objects are moved from the Container to this AnnGroupObject. This AnnGroupObject is a temporary group and will be ungrouped (by calling AnnGroupObject.Ungroup) and added back to the Container when the objects are not selected anymore (for example, by clicking somewhere in the container outside the group or by calling the user interface or by calling SelectNone). To check if the current editing object is the temporary group, first check if the CurrentEditObject is an AnnGroupObject, then check if the AnnGroupObject.Temporary value is set to true.

For more information about grouping and ungrouping, refer to Grouping and Ungrouping Annotation Objects.

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Public Sub AnnAutomation_CanGroup(ByVal automation As AnnAutomation)
   ShowStatus(automation)
   ' first, add two objects to the automation
   Dim rectObj As AnnRectangleObject = New AnnRectangleObject()
   rectObj.Bounds = New AnnRectangle(100, 100, 100, 100, AnnUnit.Pixel)
   rectObj.Pen = New AnnPen(Color.Blue, New AnnLength(1, AnnUnit.Pixel))
   rectObj.Brush = Nothing
   automation.Container.Objects.Add(rectObj)
   automation.Viewer.Invalidate(rectObj.InvalidRectangle)
   ShowStatus(automation)

   Dim lineObj As AnnLineObject = New AnnLineObject()
   lineObj.StartPoint = New AnnPoint(100, 100, AnnUnit.Pixel)
   lineObj.EndPoint = New AnnPoint(200, 200, AnnUnit.Pixel)
   lineObj.Pen = New AnnPen(Color.Red, New AnnLength(1, AnnUnit.Pixel))
   automation.Container.Objects.Add(lineObj)
   automation.Viewer.Invalidate(lineObj.InvalidRectangle)
   ShowStatus(automation)

   ' "select" both objects
   automation.StartEditing(rectObj, False)
   ShowStatus(automation)

   automation.StartEditing(lineObj, True)
   ShowStatus(automation)

   ' make this group object a true group
   If automation.CanGroup Then
      automation.Group()
      ShowStatus(automation)
   End If

   ' ungroup to again to the origina 2 objects
   If automation.CanUngroup Then
      automation.Ungroup()
      ShowStatus(automation)
   End If
End Sub

Private Sub ShowStatus(ByVal automation As AnnAutomation)
   Dim sb As System.Text.StringBuilder = New System.Text.StringBuilder()
   sb.Append("Number of objects: ")
   sb.Append(automation.Container.Objects.Count)
   sb.Append(Environment.NewLine)

   sb.Append("Object currently being edited: ")
   If Not automation.CurrentEditObject Is Nothing Then
      sb.Append(automation.CurrentEditObject.GetType().Name)
      If TypeOf automation.CurrentEditObject Is AnnGroupObject Then
         sb.Append(", Temporary: ")
         Dim group As AnnGroupObject = CType(IIf(TypeOf automation.CurrentEditObject Is AnnGroupObject, automation.CurrentEditObject, Nothing), AnnGroupObject)
         sb.Append(group.Temporary)
      End If
   Else
      sb.Append("None")
   End If

   sb.Append(Environment.NewLine)

   sb.Append("CanGroup: ")
   sb.Append(automation.CanGroup)
   sb.Append(", CanUngroup: ")
   sb.Append(automation.CanUngroup)

   MessageBox.Show(sb.ToString())
End Sub

public void AnnAutomation_CanGroup(AnnAutomation automation)
{
   ShowStatus(automation);
   // first, add two objects to the automation
   AnnRectangleObject rectObj = new AnnRectangleObject();
   rectObj.Bounds = new AnnRectangle(100, 100, 100, 100, AnnUnit.Pixel);
   rectObj.Pen = new AnnPen(Color.Blue, new AnnLength(1, AnnUnit.Pixel));
   rectObj.Brush = null;
   automation.Container.Objects.Add(rectObj);
   automation.Viewer.Invalidate(rectObj.InvalidRectangle);
   ShowStatus(automation);

   AnnLineObject lineObj = new AnnLineObject();
   lineObj.StartPoint = new AnnPoint(100, 100, AnnUnit.Pixel);
   lineObj.EndPoint = new AnnPoint(200, 200, AnnUnit.Pixel);
   lineObj.Pen = new AnnPen(Color.Red, new AnnLength(1, AnnUnit.Pixel));
   automation.Container.Objects.Add(lineObj);
   automation.Viewer.Invalidate(lineObj.InvalidRectangle);
   ShowStatus(automation);

   // "select" both objects
   automation.StartEditing(rectObj, false);
   ShowStatus(automation);

   automation.StartEditing(lineObj, true);
   ShowStatus(automation);

   // make this group object a true group
   if(automation.CanGroup)
   {
      automation.Group();
      ShowStatus(automation);
   }

   // ungroup to again to the origina 2 objects
   if(automation.CanUngroup)
   {
      automation.Ungroup();
      ShowStatus(automation);
   }
}

private void ShowStatus(AnnAutomation automation)
{
   System.Text.StringBuilder sb = new System.Text.StringBuilder();
   sb.Append("Number of objects: ");
   sb.Append(automation.Container.Objects.Count);
   sb.Append(Environment.NewLine);

   sb.Append("Object currently being edited: ");
   if(automation.CurrentEditObject != null)
   {
      sb.Append(automation.CurrentEditObject.GetType().Name);
      if(automation.CurrentEditObject is AnnGroupObject)
      {
         sb.Append(", Temporary: ");
         AnnGroupObject group = automation.CurrentEditObject as AnnGroupObject;
         sb.Append(group.Temporary);
      }
   }
   else
      sb.Append("None");

   sb.Append(Environment.NewLine);

   sb.Append("CanGroup: ");
   sb.Append(automation.CanGroup);
   sb.Append(", CanUngroup: ");
   sb.Append(automation.CanUngroup);

   MessageBox.Show(sb.ToString());
}

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

AnnAutomation Class
AnnAutomation Members