How to return reactive expression in Shiny module

[Samuel Bohman]

If I have a module that needs to return a list of reactive expressions from the module server function, is this the correct syntax?

return(list(exp_1, exp_2, exp_3))

And a follow up question is how do you use such a list of multiple reactive expressions in the server function of the Shiny app? Garrett Grolemund explains in this video tutorial that you should save the callModule() data in a variable, and then "crack" open that variable with ()' when you are going to use it. But what do you do if you have a list of several reactive expressions that contain return values for different purposes in the main app?

Thanks in advance.

[Joe Cheng]

That's correct. And if the module that returns that is called "foo" then you'd use it like this:

fooResult <- callModule(foo, "id")
fooResult$exp_1()

(You'd have to do that second line in a reactive expression or observer but hopefully you get the idea...?)

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[Samuel Bohman]

Thanks Joe. My app is running without any warnings or error messages in the Console. However, I am still not getting the results I am trying to achieve. I am using the reactive expressions in an observer, like so: https://gist.github.com/samuel-bohman/959e17e70eedb0bae527771ee7c0719a

[Joe Cheng]

That should work. Try calling str() on some of those results and make sure you're seeing the values you're expecting?

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[Samuel Bohman]

How and when do I do that while the app is running? I'm sorry, I'm a beginner in Shiny!

[Samuel Bohman]

Here is the link: https://xplor.shinyapps.io/xplor/ My current hypothesis is that input$alt is empty because it is rendered through a renderUI in the module server. This causes the app not to work because of the null_check() function in server.R. I'm planning to eliminate the null check functions and use req() instead, but it has not worked out for me so far. Thanks again Joe, you are very helpful and I appreciate your help a lot!