Hi why Slider onValueChanged is being triggered on every state change? I think onValueChange must be called when user interacts with the slider isn’t it?

please file as a bug

I suppose it is changing when the position parameter changes, or when a user is dragging? The former would be a bug, the later would be expected behavior.

I see there another param

onValueChangeFinished

Then, should we store two values first is main value second is awaiting user interaction?

Why do you have a userPosition if you are not passing it to the slider?

There is a media player listener which updates position value

Oh,

onValueChangeFinished

doesn't have a value parameter, eww

Yes a bit strange ))

I am not following what the problem is. You are getting callbacks without moving the slider? Other than this bug I haven't seen anything like that in my slider.

Seems you are experiencing this issue: https://issuetracker.google.com/u/0/issues/175943373

That is the same issue I cited (which happens to be the one you alerted me to in January :) ) but I don't think it applies here (though I can't tell without more information). The slider will always tell you where it is so that you can update its movement, regardless of whether you want the "intermediate" values or not. You don't want the thumb to move until you stop dragging?

I think the linked issue is exactly what is happening here. The onValueChange lambda is getting called without touching the slider. The issue is currently preventing me from using the Compose slider, unfortunately.

For me, the linked issue only happens when I give the slider its initial value (and I was able to work around it). RUSTAM, can you post a minimal repro in text (in particular, how are

position

and

userPosition

declared)?

Hi @Rick Regan

I think onValueChange fires on any value change by user or by state.

At the moment it is called by user and by state changes, but the latter is a bug which was confirmed in the linked issue.

I constructed this code from your screenshots. First a question: does this capture your code, or am I missing an important element? If the latter, please post something that matches your problem.

@Composable
fun SliderTest() {
    println("SliderTest: Composed")
    var position by remember { mutableStateOf(0f) }
    var userPosition by remember { mutableStateOf(0f) }
    Slider(
        value = position,
        onValueChange = {
            userPosition = it
            println("SliderTest: Position changed: userPosition = $userPosition (position = $position)")
        },
        onValueChangeFinished = {
            position = userPosition
            println("SliderTest: User selected position: (position = $position)")
        }
    )
}

@Rick Regan Yes exactly . But then I removed userPosition

I had assumed something was different with my code because when I run it (beta01) the slider can be moved right, but not left! Is that what you saw too? Here's a look at example output of the code I posted. To make the messages easier to decipher (i.e., fewer of them) I just clicked the mouse at one point on the slider. First note that upon initialization, bug 75943373 hits:

...I/System.out: SliderTest: Composed
...I/System.out: SliderTest: Position changed: userPosition = 0.0 (position = 0.0)

Clicking to the right (the thumb jumps as expected) gives:

...I/System.out: SliderTest: Position changed: userPosition = 0.8638611 (position = 0.0)
...I/System.out: SliderTest: User selected position: (position = 0.8638611)
...I/System.out: SliderTest: Composed

But then clicking to the left (the thumb doesn't move) gives:

...I/System.out: SliderTest: Position changed: userPosition = 0.087005615 (position = 0.8638611)
...I/System.out: SliderTest: Position changed: userPosition = 0.8638611 (position = 0.8638611)
...I/System.out: SliderTest: User selected position: (position = 0.8638611)

Thomas, that second callback is likely bug 75943373 as well, as you suspected. It overrides the position with the old position. I don't know why it only happens in that direction though. This has not been a problem in my app (except at initialization), maybe because I don't use

onValueChangeFinished.

Yes. The same happened with my code. When I declared two variable states

I'm hoping now that beta's here that some of the

Slider

issues will be addressed.