Some of ClearSCADA's functions and properties use the legacy term "head" to identify a particular monitor in a multi-monitor setup. To enable these functions to operate as intended, you need to allocate head numbers to the Window Containers included in the Startup Configuration File.This will allow a Window Container to emulate the role of a head.
If a function uses a head number that does not correspond to a Window Container, the associated script will return a diagnostic message.
The functions and properties that use the term "head" are:
- App.Head (a property of the Application script object)
- App.OpenWindowOnHead (a function of the Application script object)
- App.NavigateOnHead (a function of the Application script object)
- HEAD (an expressions function).
If any of these are implemented in your ClearSCADA system, you need to determine how the head definitions are used and assign matching head numbers to the Window Containers configured in the Startup Configuration File.
To specify a head number for a Window Container, use the LegacyHead element.
Example:
The following line of script uses the App.OpenWindowOnHead function to display a mimic on head 2.
App.OpenWindowOnHead (2,"SCX:////CMimic/.System Overview")
To enable this function to work correctly on a system using Window Containers, you would need to set the LegacyHead element to 2 for the appropriate Window Container.
<SecondaryWindowContainer Monitor="2" LegacyHead="2" Name="Left" />
Attention: If a head number is not specified for a Window Container, the system will automatically assign a number based on the order in which the Window Containers are defined in the Startup Configuration File. This may produce unexpected results. To avoid this situation, you should manually assign head numbers to Window Containers.