Filter a lookup field based upon another lookup field in the same form

Filter a lookup field based upon another lookup field in the same form

Hopefully someone can help me. I have 3 forms: 
  • Project Info -- contains high-level information about a project.
  • Course Info -- contains information about each course associated with a project. There may be multiple courses associated with one project, and each course MUST be associated with a project. The Course Info form contains a lookup field which points to Project_Name in the Project Info table. 
  • Task Manager Test -- In this form, I want the user to be able to first select a Project Name. Then, based upon that Project Name, select a course. I have a lookup field that points to Project_Name in the Project Info table. I want to limit the courses that appear in the Course Name lookup field to only those courses associated with the previously-selected project name. 
  • I'm trying to do this with the Set Filter choice, using what SEEMS to be the terminology suggested by help documentation (which does not appear to actually reference the current programming build, sigh), and edited after I save the form (For example, the ".toLong()" function was added by the system). The code I'm trying to use is: Project_Name == "course_info.Project_Name.toLong()"
  • However, when I access the application and select a Project from the Project Name dropdown, the Course Name field remains empty, no matter what I do. 
Help a newbie out please??? 

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