The name of the Webroutine to be invoked when the weblet is clicked.
Default value
Blank – a Webroutine name must be specified.
Valid values
The name of a Webroutine in single quotes. The Webroutine must exist in the WAM specified in the on_click_wamname property. A list of known Webroutines can be displayed by clicking the corresponding dropdown button on the property sheet.