Windows.KeyDown Event (Visio)
Occurs when a keyboard key is pressed.
Private Sub expression _'KeyDown'(ByVal KeyCode As Long , ByVal KeyButtonState As Long , ByVal CancelDefault As Boolean)
expression A variable that represents a Windows object.
|KeyCode||Required||Long||The key that was pressed. See Remarks for possible values.|
|KeyButtonState||Required||Long||The state of the SHIFT and CTRL keys for the event. See Remarks for possible values.|
|CancelDefault||Required||Boolean||False if Microsoft Visio should process the message it receives from this event; otherwise, True .|
Possible values for KeyCode are declared in KeyCodeConstants in the Microsoft Visual Basic for Applications (VBA) library.
Possible values for KeyButtonState can be a combination of the values shown in the following table, which are declared in VisKeyButtonFlags in the Visio type library. For example, if KeyButtonState returns 12, it indicates that the user held down both SHIFT and CTRL.
If you set CancelDefault to True , Visio will not process the message received when the mouse button is clicked.
Unlike some other Visio events, KeyDown does not have the prefix "Query," but it is nevertheless a query event. That is, you can cancel processing the message sent by KeyDown , either by setting CancelDefault to True , or, if you are using the VisEventProc method to handle the event, by returning True . For more information, see the topics for the VisEventProc method and for any of the query events (for example, the QueryCancelSuspend event) in this Automation Reference.
Pressing an accelererator key combination, for example, CTRL + C, does not fire the KeyDown event.
If you are using VBA, the syntax in this topic describes a common, efficient way to handle events.
If you want to create your own Event objects, use the Add or AddAdvise method. To create an Event object that runs an add-on, use the Add method as it applies to the EventList collection. To create an Event object that receives notification, use the AddAdvise method. To find an event code for the event you want to create, seeEvent codes.
This class module shows how to define a sink class called KeyboardListener that listens for events fired by keyboard actions in the active window. It declares the object variable vsoWindow by using the WithEvents keyword. The class module also contains event handlers for the KeyDown , KeyPress , and KeyUp events.
To run this example, insert a new class module in your VBA project, name it KeyboardListener , and insert the following code in the module.
Dim WithEvents vsoWindow As Visio.Window Private Sub Class_Initialize() Set vsoWindow = ActiveWindow End Sub Private Sub Class_Terminate() Set vsoWindow = Nothing End Sub Private Sub vsoWindow_KeyDown(ByVal KeyCode As Long, ByVal KeyButtonState As Long, CancelDefault As Boolean) Debug.Print "KeyCode is "; KeyCode Debug.Print "KeyButtonState is" ; KeyButtonState End Sub Private Sub vsoWindow_KeyPress(ByVal KeyAscii As Long, CancelDefault As Boolean) Debug.Print "KeyAscii value is "; KeyAscii End Sub Private Sub vsoWindow_KeyUp(ByVal KeyCode As Long, ByVal KeyButtonState As Long, CancelDefault As Boolean) Debug.Print "KeyCode is "; KeyCode Debug.Print "KeyButtonState is" ; KeyButtonState End Sub
Then, insert the following code in the ThisDocument project.
Dim myKeyboardListener As KeyboardListener Private Sub Document_DocumentSaved(ByVal doc As IVDocument) Set myKeyboardListener = New KeyboardListener End Sub Private Sub Document_BeforeDocumentClose(ByVal doc As IVDocument) Set myKeyboardListener = Nothing End Sub
Save the document to initialize the class, and then press any key to fire a KeyDown event. In the Immediate window, the handler prints the code of the key that was pressed to fire the event and the state of the SHIFT and CTRL keys at the time the event fired.