[Felgo User]

I create an AppButton then each time user click it, it change the text of the button to the next char/string in an array like this

import Felgo 3.0
import QtQuick 2.0
AppButton{
 id:questButton
 property var arrayOfChar = ['a', 'b', 'c', 'd', 'e', 'f']

 property string testChar
 
 onClicked: {
 var numOfChar = entry.length
 var random = utils.generateRandomValueBetween(0, numOfChar-1)
 var testChar = entry[random]
 questButton.text = testChar
 }
}

I guessed the text changing will happened easily but I got this errors V_Play_Desktop_Qt_5_11_1_MinGW-Debug/qml/QuestButton.qml:20: Error: Cannot assign [undefined] to QString. What wrong I have done and is there a more standard way to do like I said?

[GüntherFelgo Team]

You can do something like this, if you face this error, there’s probably an issue in your user code. Sounds like the value you are trying to fetch does not exist in the array.

[Felgo User]

Thank you for the hint. The problem now can be solved by add Math.round

var random = Math.round(utils.generateRandomValueBetween(0,numOfChar - 1))

I didn’t test the output of function generateRandomValueBetween and misunderstanding that it will generate only integer.