Interface Definition: Expression evaluation error at function a!dropdownField [line 9]

Hi,

One possible cause of this issue comes from casting. It's possible that the value selected is a different type than the choice values.

I hope this helps.

To clarify -

Consider the following code block.

a!dropdownField(
    choiceValues:{1,2,3,4},
    choiceLabels:{1,2,3,4},
    value:"2"
)...

This will give you an error of  - Interface Definition: Expression evaluation error at function a!dropdownField [line 12]: A dropdown component [label=“”] has an invalid value for “value”. All selected values must be present in the choiceValues array, but value was 2 and choiceValues was 1; 2; 3; 4.

This is because the value is a string, and not an integer, therefore it is not 2, it is "2".

By casting the value to the same type as the choiceValues (from a string to an integer), you would be able to fix this problem.

E.G: 

a!dropdownField(
    choiceValues:{1,2,3,4},
    choiceLabels:{1,2,3,4},
    value:tointeger("2")
)...

This may not be the solution to your problem, however without more context, that is the immediate problem that pops into mind for me.

Hope this is helpful!