ActiveX controls are programmable objects that you can use to add functionality to a drawing. For example, you might insert standard Microsoft Windows dialog box controls, such as option buttons, check boxes, or list boxes; or custom controls that provide more complex functionality, such as animation.

To program a control, you typically write event procedures in the drawing's Microsoft Visual Basic for Applications project to handle the control's events, and you can get or set the control's properties or invoke its methods in other procedures.

Most controls come with a Setup program that installs and automatically registers the control. If you copy an ActiveX control (a file with an .ocx or .dll extension) from an installation disk or from a network without using a Setup program, the control might not be registered or appear in the Controls list. You must register the control before you use it.

Notes

Use caution when you are adding ActiveX controls to your document. ActiveX controls may be designed in such a way that their use could pose a security risk. We recommend that you use controls from trusted sources only.

When the security level for Microsoft Office Visio is set to Medium or High and an ActiveX control is not from a trusted source, you and other users might not be able to insert the ActiveX control in the document and the control might not load when the document opens. Users with Medium and High security level settings also might experience problems reading a document that contains an embedded ActiveX control. If you embed a control from an untrusted source in your document, other people might not be able to use the document.

For more information about ActiveX controls, see the Visual Basic Editor Help.