Non-repetitive random code that changes color

[Carlos_Andres_Medina (Carlos Andrés Medina)]

How can I design a non-repetitive random code that changes color when approved?

[Still-learning (1-2-3-4...)]

@Carlos_Andres_Medina

non-repetitive random code

Already @Taifun shared about this kind of stuffs in his snippets

App Inventor Code Snippets | Pura Vida Apps

[dora_paz (Dora)]

@Carlos_Andres_Medina

a non-repetitive random code

Do you mean something like random unique password ?

@Carlos_Andres_Medina

when approved?

approved by whom ?

[Carlos_Andres_Medina (Carlos Andrés Medina)]

requires the configuration of the qr code option to establish an order of command when it is accepted change to a different color and likewise when it is denied it put another color