List Error: is not a uistring

I see this type of error A LOT when we are using Lists:
setProperty() id parameter refers to an id (“txtError”) which does not exist. You should be able to find the list of all the possible ids in the dropdown (unless you created the element inside your code).WARNING: Line: 10: setNumber() value parameter value (90,100,85,77) is not a number.WARNING: Line: 10: setText() text parameter value (90,100,85,77) is not a uistring…]
Can someone explain please? Thank you in advance!

What I’ve tried: [replace with a detailed description of what you’ve already tried to do to solve the problem]

You have this line of code

var gradeList = [90, 100, 85];

and then this

	setNumber("gradeOutput", gradeList);

Think about what type of parameters setNumber expects. Try putting console.log(gradeList); in front of that call to setNumber to see what you are sending it.

Ok thanks! It’s a list (as expected) [90, 100, 85, 77] So how do you display the lists in the labels then? What type is it? I have tried setText and set Property… same error.
I also have looked through Lesson U5 L3 and all of the example problems print out to the console… I am not seeing one that shows a list in a label?
I am guessing I need to loop and add each element to the label output… one at at time?
Thanks for your time and help.

Go back to setText. (Look at line 4.) App Lab is really good at changing things into strings.

One reason you might want to use a loop is to format it differently from what App Lab does.