Leadtools.Annotations Requires Document/Medical product license | Send comments on this topic. | Back to Introduction - All Topics | Help Version 15.10.31
UndoRedoChanged Event
See Also  Example
Leadtools.Annotations Namespace > AnnAutomation Class : UndoRedoChanged Event




Occurs when the undo or redo buffer changes.

Syntax

Visual Basic (Declaration) 
Public Event UndoRedoChanged() As EventHandler
Visual Basic (Usage)Copy Code
Dim instance As AnnAutomation
Dim handler As EventHandler
 
AddHandler instance.UndoRedoChanged, handler
C# 
public event EventHandler UndoRedoChanged()
Managed Extensions for C++ 
public: __event EventHandler* UndoRedoChanged();
C++/CLI 
public:
event EventHandler^ UndoRedoChanged();

Example

This example updates an Undo and Redo menu handler's status.

Visual BasicCopy Code
Public Sub AnnAutomation_UndoRedoChanged(ByVal manager As AnnAutomationManager)
   ' subscribe to the UndoRedoChanged event of all automations
   For Each automation As AnnAutomation In manager.Automations
      AddHandler automation.UndoRedoChanged, AddressOf automation_UndoRedoChanged
   Next automation
End Sub
Private Sub automation_UndoRedoChanged(ByVal sender As Object, ByVal e As EventArgs)
   Dim automation As AnnAutomation = CType(IIf(TypeOf sender Is AnnAutomation, sender, Nothing), AnnAutomation)

   ' assume _menuItemUndo is the Undo menu, and _menuItemRedo is the Redo menu
   _menuItemUndo.Enabled = automation.CanUndo
   _menuItemRedo.Enabled = automation.CanRedo
End Sub
C#Copy Code
public void AnnAutomation_UndoRedoChanged(AnnAutomationManager manager) 

   // subscribe to the UndoRedoChanged event of all automations 
   foreach(AnnAutomation automation in manager.Automations) 
      automation.UndoRedoChanged += new EventHandler(automation_UndoRedoChanged); 

private void automation_UndoRedoChanged(object sender, EventArgs e) 

   AnnAutomation automation = sender as AnnAutomation; 
 
   // assume _menuItemUndo is the Undo menu, and _menuItemRedo is the Redo menu 
   _menuItemUndo.Enabled = automation.CanUndo; 
   _menuItemRedo.Enabled = automation.CanRedo; 
}

Remarks

This event will be fired when the undo/redo buffer changes. This gives the application a chance to update the user interface if needed.

The undo/redo buffer changes whenever an object inside the Container changes either by user interaction through the user interface or by code.

You can use the CanUndo and CanRedo property to determine whether this AnnAutomation can undo or redo an operation.

For more information, refer to Undoing Automation Operations.

Requirements

Target Platforms: Microsoft .NET Framework 2.0, Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

Leadtools.Annotations requires a Document or Medical toolkit license and unlock key. For more information, refer to: Raster Pro/Document/Medical Features