At first glance, MutableState and MutableStateFlow work equally well in Composable. What is better to use?

In my observations/opinion, the Compose compiler plugin generates some stubs to redraws only things whose state have been changed. You can always collect a state flow with a

.collectAsState()

to get state representation of the StateFlow. As far as I understood, every event fires redraw event of all the children UI elements, but only whose state changed actually gets executed and changed. When using a StateFlow, and directly calling

StateFlow.value

you'll be redrawing the UI for every single event like mouse move, mouse enter, mouse click, to the element you are using it with, even if the value wasn't changed.

I don't seem to understand their mechanisms. I made an experiment to check the repetition of redrawing when the value did not change and got no redrawing at all even when the value changed... I'll look at this in more detail

Have you checkedJetpack Compse doc? Path way is very good starting point https://developer.android.com/courses/pathways/compose

I would reach for Flow-based tools first, since they rely on less magic and are easier to test with, imo. It also keeps the non-compose bits of your code compose-free, which can make it easier to refactor modules later on.

For everything outside of a

@Compose

function, I use

Flow

(or whichever subclass is appropriate, e.g.

StateFlow

), because

Flow

is fairly universal. However, the first few lines of my

@Compose

functions all convert those to

State

via

collectAsState()

because I know the composables will properly handle updates to

State

.