Rockwell Automation 9301 Series RSView32 Users Guide - Manual (Page 366)

Creating graphic displays
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11–73
Creating and editing ActiveX objects
An ActiveX object is a software component that is supplied
independently from RSView32 through products such as Microsoft
®
Visual Basic, Office 97, and many other third–party applications. An
ActiveX object provides functions that can be accessed through the
object’s properties, events, and methods. By embedding an ActiveX
object in an RSView32 graphic display and then assigning properties
or specifying handlers for the object’s events, the object can interact
with RSView32. Information is passed between an ActiveX object and
RSView32 using RSView32 tags.
For example, you can embed a third-party gauge in an RSView32
graphic display and attach an RSView32 tag to the gauge’s Value
property. As the tag’s value changes, the gauge’s needle changes
position to reflect the tag’s value.
To pass information between an ActiveX object and RSView32,
information must be in the same format as the RSView32 tags, that is,
an analog or digital number, or a string. RSView32 does not support
pointer parameters in an ActiveX object.
An ActiveX object has three types of attributes:
Properties: named characteristics and values of an object such as
shape, color, position, or number. For details about attaching control
to an object’s properties, see page 12-36.
Events: actions triggered by the ActiveX object in response to an
external action on the object, such as a mouse click. In RSView32 you
can use events to change the value of an RSView32 tag or to run an
RSView32 command or a macro. When the event happens, the
command or macro runs. To use the ActiveX object to change a tag’s
value, associate the tag with one of the object’s event parameters. For
details about attaching control to an object’s events, see page 12-38.
Methods: functions implemented in the ActiveX object that allow
external actions to change the object’s appearance, behavior, or
properties. A call to a method might be made in response to events