<onvariable> Element

This element defines the data type of the variable which triggers the creation of the HMI symbol instance or symbol group on the HMI page or the folder under the 'Application' node in the PLANT.

Parent elements: <group>, <symbol>, <folder>

Attributes:

Attribute Description Type / Required

id Unique identifier that defines the data type of the variable instance that triggers the creation of the HMI symbol instance or symbol group defined by the parent <symbol> or <group> element or the folder defined by the parent <folder> element. Type: string
Required: yes

name Defines the name of the variable that triggers the creation of the symbol instance/symbol group. Type: string
Required: no

unique Specifies whether the symbol instance/symbol group/folder should be created once or as many times the variable exists.
If set to "true", the symbol instance/symbol group/folder is created once, even if the triggering variable exists two or more times in the project. Type: boolean true or false (default)
Required: no

level Specifies the level of the function block or program instance as represented in the PLANT that contains the variable that triggers the creation. You can use this attribute to limit the creation to a specific node level.

Further Info
For details on the node level and how to use the attribute, see the description of the <onfunctionblock> element.

Type: string
Required: no