Note that when using a Declare Trigger to run a trigger activity, the activity does not have a parameter page. This has the following effects:
Any reference to a parameter will cause the activity to fail with a Java nullPointerException.
Any use of looping constructs will also cause a Java nullPointerException, as PRPC will attempt to create and update properties such as Param.pyForEachCount.
Local variables are acceptable. If you need to loop, call a child activity (normal, not trigger) which will have its own parameter page. If you need to pass parameters into this child activity you will have to do it directly (rather than set the parameter values and ticking the “Pass current parameter page” checkbox as this won’t work).
PRPC will not generate any compilation warnings if parameters are used but the activity will fail at run time immediately upon hitting one.