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HOW DOES ROM WITH A VIEW USE ACTIVEX ?
ACTIVEX CONTROL OBJECT
There several methods available to insert an ActiveX Control.
A brief wizard will assist in defining specific properties
of an ActiveX Control.
The two following methods will bring up the Insert Object
Wizard with the first page asking what type of Object is being
inserted:
- In the Treeview or Page Editor, right-click on the Page
and select New, then Object.
- In the Treeview or Page Editor, if there are already Objects:
right-click the Object, select New , then Object.
Select ActiveX Control, click Next. The Add an ActiveX Control
pages will appear. The two following methods will skip the
first page of the Insert Object Wizard:
- From the Menu Bar, click the Insert Menu, and select Insert
ActiveX Control.
- From the Toolbar, single click the image that highlights
as Insert ActiveX Control.
ACTIVEX CONTROL WIZARD
The first page of the Wizard asks what ActiveX Control is
to be inserted. The list generated includes the ROM With
a View suite of ActiveX Controls as well as any
registered ActiveX Controls on your WIN 95/98 machine. Any
of these ActiveX Controls can be easily incorporated into
a project.
To select an ActiveX: scroll through the generated list or
use the Find button to browse. When an ActiveX is selected,
the location and Class ID of the control will appear in the
lower right corner of the Wizard page.
After selecting the ActiveX Control to be inserted, click
Finished. The ActiveX Control will appear on the Treeview;
on the Page Editor the Control is displayed as a gray rectangle
in the upper left corner (0,0). To reposition the Control
click and drag it to the desired location; to resize the control,
click a corner or edge and drag to create the desired size.
Once the ActiveX Control has been added, the next step is
to insert the appropriate Events, Methods, and Properties
to enable the Control to function.
The more familiar one is with the ActiveX Control being
used, the easier it is to use its Methods, Properties, and
Events.
INCLUDING ACTIVEX CONTROLS ON THE
CD
In order for an ActiveX Control in a ROM With a View
application to work on the end user’s computer, the ActiveX
Control must exist and be registered on that computer. In
the event that a ROM With a View application encounters
a requirement for an ActiveX Control that the computer
does not have, the application will simply ignore the command
and proceed to the next step.
A ROM With a View application using ActiveX Controls
requires the following:
- Knowledge of the ActiveX Control(s) being used in the
application (name of Control, the class ID, and the version
number)
- The ability to check the end user’s computer for
the ActiveX Control(s) being used
- The ability to write any missing ActiveX Control(s) to
the end user’s Hard Drive
- The ability to register the new ActiveX Control(s) added
to the Hard Drive
Note: Some ActiveX Controls may have licensing requirements
and involve entries in the System Registry. Licensed controls
usually come with setup programs that take care of these details.
The redistribution rights, proper installation, and registration
of the ActiveX Controls are the responsibility of you, the
author. Refer to the author or publisher of the ActiveX Control
to insure correct installation and use.
The inclusion of this information in a ROM With a View
application is easily done with a utility [Makecab] included
with the ROM With a View program. This .cab file includes
an .inf which will automatically check the end user’s
computer for the above information and take care of writing
and registering any ActiveX Control(s) that are found to be
missing. This can also be done manually.
ADDING OR CHANGING A PROPERTY OF AN
ACTIVEX CONTROL
Changing the Property of a Control is accomplished by adding
a Set Property ScriptItem to an Event.
Right-click the Event, select New, then select ScriptItem.
The ScriptItems page will appear, select SetProperty, click
OK.
On the SetProperty page use the drop down arrow to find the
ActiveX Control to be modified. Once the Control is selected,
click the Change Property button.
A Property page for the ActiveX Control will appear; this
page has four fields to fill out: Object, Property, Variable,
and New Value.
OBJECT
This is the Object whose property is being changed.
Note: The ActiveX Control selected on the previous
screen will be highlighted in this line.
PROPERTY
This is the property to be changed. Clicking the down arrow
will show a list of the properties applicable to the object
selected in the Object line.
Note: To the left of the Property line is a box
that will display the variable type of the selected Property.
VARIABLE
If the selected Property is to be modified by a variable,
select the variable.
Note: If no variables have been created, this
line will be grayed out.
Note: To the left of the Variable line is a box that
will display the variable type of the selected Variable.
NEW VALUE
This is the new value of the Property being changed.
Note: The new value variable type must agree
with the variable type shown in the box to the left of the
selected Property.
Set the fields, click OK.
A SetProperty ScriptItem will appear below the Event.
USING OBJECT EVENTS TO CALL ACTIVEX
METHODS
Any Object (Button, Image, Text) can be used to trigger an
ActiveX Control.
Adding the appropriate ScriptItem to the Object’s Event
[Call ActiveX Method or Set Property] will enable the
Object to trigger the ActiveX Control.
USING RETURN VALUES WITH ACTIVEX
CONTROLS
In order for a Return Value to be of use, there must be notification
that the Return Value was received and recognized. This can
be done by creating a variable to which the Return Value is
written when a specific Method is called. Once the information
is received and written to a variable, the information can
then be utilized by the Global Event OnChange. OnChange can
be scripted to look for a specific change (the new value of
the variable) and when found, perform the desired tasks.
The first step is to create the variable. This is done by
using the ScriptItem, Create Variable.
Note: We recommend that the variable types
of the Return Value and the Variable agree
Once you have created the variable, add the corresponding
Property or Method to receive the Return Value. On the Call
ActiveX Method ScriptItem page is a dialog box to designate
the name of the variable to write a Return Value. Select the
Method to be called; select the variable to write the Return
Value; click Ok. You can add additional script items as you
choose.
Now the OnChange event can be scripted to perform a task
based upon the Return Value of the ActiveX Control. To make
use of the OnChange Event the following must be added to the
event:
The Property or Method of the ActiveX Control whose change
is being monitored.
The comparison Item or Variable.
The Script(s) of what will happen when the change occurs.
THE BASICS OF ADDING FUNCTION TO
AN ACTIVEX CONTROL
Depending on the ActiveX Control being used, Methods, Properties,
and Events will need to be added in order for the Control
to work properly.
To Add an Event to an ActiveX Control:
Right-click the ActiveX and select New, then select Event.
The Add Events page will appear with a list of all the events
specific to the ActiveX Control. This list is generated by
the program querying the ActiveX Control and the Control answering
with what it is capable of doing. This list can vary from
a few events to a very long list. An example of a control
with many Events is the Microsoft Office Spreadsheet ActiveX.
Select the Event to add, click OK.
The Event will appear on the Treeview below the ActiveX Control.
To enable the Event one or more ScriptItems will need to
be added. The types of ScriptItems generally added are: Call
ActiveX Method, and SetProperty.
To Add a Method to an ActiveX Control:
A Method is called by adding the ScriptItem Call ActiveX
Method to an Event of the Control. Right-click the Event that
will call the Method and select New, then select ScriptItem.
The ScriptItems page will appear, select Call ActiveX Method,
click OK. The Call ActiveX Method Properties page will appear.
On the left is a drop down list containing all the ActiveX
Controls on the current page of the project. Select the ActiveX
Control for which the Method is being called. Once the Control
is selected, the list to the right will present the corresponding
Methods available for that Control. When the Method is selected,
the known parameters of the Method will appear in the box
to the left of the list.
If a Parameter needs to be designated for the Method, click
the Parameter tab.
If a Return Value is associated with the Method being called,
the Return Value tab will appear.
To designate the variable for writing of the Return Value,
click the tab and select the variable to be used.
Once the Method, Parameter(s), and or Return Values are designated,
click OK.
The CallActiveXMethod ScriptItem will appear below the Event
to which it was added.
Note: A Call ActiveX Method ScriptItem
can be associated with any type of Event on any type of Object.
The Event does not have to be an ActiveX Control, any Objects’
Events can Call an ActiveX Method and trigger the Control.
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