Hi ! As a experiment and in order to understand why a part of my project does not work, I've created this ColorSquare experiment. 1. It is a simple `@Composable`which outputs a

Surface

with solid background color, and a

Button

. 2. When the user clicks on the button, the expected behaviour is that the square changes its color. 3. In this experiment, things are a bit more complicated : I'm using a

ColorSquareState

class, with a method

chooseNextColor

, and I'm storing a `mutableState`on an instance of this class. But when the `chooseNextColor`is called, it does not force recomposition. Why ? Is there a simple workaround keeping the use of `ColorSquareState`as long as method

chooseNextColor

?

The field you update should be backed by

State

. In your snippet the whole

ColorSquareState

is wrapped in the

State

and Compose are subscribed to it’s changes, but you are mutating the property inside

ColorSquareState

, which is not a

State

. So try the following: 1. Declare the property as

State

:

var bgColor by mutableStateOf(blue)

2. Remove unnecessary

mutableStateOf

for the whole state:

val color by remember { ColorSquareState() }

Thank you I'm gonna try now 🙂