Is there a way to "detach" a value from a

@Model

so that it stops getting updated when the field it is read from changes?

Just curious, are there any recommendations on how navigation should be handled in a compose app?

Align + Column behaviour isn't working as i would expect it to

Are there any plans to make something similar to XML's

@tools:sample

with tools-provided sample data that are only available in

@Preview

Composables and that aren't shipped to the actual builds? 😍 I'd especially like this with regards to image resources. Strings I can hard code in my previews. 🙂

Editor is a bit flaky at times

Is there a way to batch

@Model

mutations so that the component sees multiple var changes at the same time?

Tooling question: I like that it's easy to navigate specifically to classes in Studio (Ctrl-N) as separate from navigating to a file (Ctrl-Shift-N). Will there be first-party support for navigating specifically to a

@Composable

by name in the future, you reckon?

For some reason i keep getting the following exception each time i add a call to the function

vectorResouce

or

stringResource

java.lang.IllegalStateException: Backend Internal error: Exception during code generation

Has anyone had the same issue before?

during gradle sync in IDEA (latest eap version)

Cannot convert string value 'JETPACK_COMPOSE' to an enum value of type 'com.android.builder.model.AndroidGradlePluginProjectFlags$BooleanFlag' (valid case insensitive values: APPLICATION_R_CLASS_CONSTANT_IDS, TEST_R_CLASS_CONSTANT_IDS, TRANSITIVE_R_CLASS)

happened to anyone? build itself succeeds

Is there any way to add a background color to a Column or Row without wrapping them in a surface?

The compiler chokes on when-in expressions.

So, effects and the unaryPlus have been removed. How would the following code be rewritten to follow the latest fashion in Compose? I think it was originally written in an article by @Luca Nicoletti and doesn't compile anymore on Dev04:

// general purpose observe effect. this will likely be provided by LiveData. effect API for
// compose will also simplify soon.
fun <T> observe(data: LiveData<T>) = effectOf<T?> {
    val result = +state<T?> { data.value }
    val observer = +memo { Observer<T> { result.value = it } }

    +onCommit(data) {
        data.observeForever(observer)
        onDispose { data.removeObserver(observer) }
    }

    result.value
}

Ref: https://medium.com/swlh/android-mvi-with-jetpack-compose-b0890f5156ac

So I know there was a session, I think that @Leland Richardson [G] did at DevSummit about how Compose actually implements its Builders, is there a document? also, lemme cast a vote for an example that shows a builder (domain-specific) that fronts compose…

any known issues with DrawVector?

in term of future plans, could compose be used in iOS?

which sample apps and tutorials are you guys using to get the hang of compose so far?

image.png

i think someone else also reported this bug. i believe it is a bug in IR implementation (specifically, using the

in range

syntax in a when expression)

There is a way to rotate a text ? Something like: Rotate(90){ Text("This is a test") }

@Composable fun Outer(i: Int, onClick: () -> Unit) {
        @Composable fun Capturing() {
            Text(i.toString())
        }
        Capturing()
        Button(onClick = onClick) {
            Text("me " + i)
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            Column {
                var i by state { 0 }
                Outer(i, {
                    i += 1
                })
            }
        }

it seems nested functions can be defined but they are not working properly,

Capturing

is considered not depending on any parameters, so it will not update when recompose

hi ya'll! I'm a compose noob (but a fair amount of kotlin experience) who is trying to convert my app over to compose - partly as an experiment and partly because I love reactive frameworks. A question: What is the best "compose way" to run code when the view changes? i.e. based on changes to a "screen" model variable it nicely changes which content gets generated. But when I change to my "bluetooth scan screen" I need to start the android BTLE scan operation (with a callback that gets invoked to add elements to my model "list of bluetooth devices"). When that screen goes away (because the screen variable got changed). I need to run some code to stop and destroy the BLE scanner class.

when (screen) {
    is Screen.Home -> HomeContent()
    is Screen.SelectRadio -> BTScanScreen()
    // Question: how to get hooks invoked when this screen gets shown/removed?
    // i.e. I need to start/stop a bluetooth scan operation. depending on the
    // appearance/disappearance of this screen.
}

Is it not possible to read from a

@Model

var outside a

@Composable

?

does it recycle?

before I make something (possibly ugly) myself, is there something like a WithActivity {} or WithApplication {} Compose functions to provide the current activity or application context (which is sometimes needed for low level android calls). I've looked through https://developer.android.com/reference/kotlin/androidx/compose but so far no luck.

Another question (heh): How do I enable/disable a component in compose? Is there some sort of Composable I nest it inside or some other concept? (In my case I have a list of bluetooth devices RadioGroupTextItems inside of a RadioGroup. And I want some of those items to be drawn grey/disabled because they are not yet paired with the phone (so I want the user to know they exist, but you can't yet select them)

I noticed there’s a

Padding

composable, but also a modifier

LayoutPadding

. When would you use one over the other? Are there plans to deprecate one of them?

And another question: What’s the current way to add Opacity to a text?

dev-03

used

withOpacity

but that was marked as a hack. Is the

Opacity

composable the only way to do it in

dev-04

?

hi, this may well be nothing but the Jetpack Compose tutorial (https://developer.android.com/jetpack/compose/tutorial) at one point outlines using a

DrawImage

compose call inside another composable. No issue up until this point but

DrawImage

comes up as an unresolved reference. Is the tutorial not up to date?

So in my app which I'm Composemotizing, I've been using the Google sign View (which looks like a button but from looking at the .class file is actually a FrameLayout. the xml style instantiation looks like:

<com.google.android.gms.common.SignInButton
 android:id="@+id/sign_in_button"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content" />

Is there any way in Compose for me to create View instances as a child of a Compose frame? From looking at the docs, I see https://developer.android.com/reference/kotlin/androidx/compose/adapters/package-summary which sounds interesting, but I'm not sure what the intended usage is?

Greetings composers! still messing with compose quite a bit, was wondering what you guys think of making more complex UI such as this fretboard chart in screenie. Questions is - Should be done using high level composables

Container

,

ColoredRect

etc or should something like this be done with low level

Canvas

draw routines?