You can do that by randomizing the total number of items in array example if the items are 10, then randomize first and pass it to a variable. later use that variable to call the array value. Copy the code below and paste in Activity Create Sub and Run
Dim myArray As List ' Declare your Array
myArray.Initialize() ' Initialize array
myArray.AddAll(Array As String("January","February","March","April"))
'Since array values index starts from zero, then four items in a list will be from 0 to 3.
'So randomize 0 to 4
Dim randNum As Int
randNum = Rnd(1,4) 'Generating random number
Log ("Current RAndom Number is " & randNum) 'This will print the random number
'=========PRINT RESULT TO LOGCAT ======
'Since we are generating from 1 to 4, we use -1 (4-1=3 ie April ==Array index starts from 0 to 3)
Log(myArray.Get(randNum-1))