Is making impossible for me to have an AdapterList and add new values for my MutableList with a Button. I keep getting:

Functions which invoke @Composable functions must be marked with the @Composable annotation

Any ideas?

if I remove the comment, sends the error cc @Adam Powell

Hi guys, Compose already have a easy way to do Shared Element Transition? Like Hero widget in Flutter or ActivityOptions.makeSceneTransitionAnimation

What sort of preview speeds are you guys getting? What can be done to speed them up?

dear composegeeks. Is https://cs.android.com/androidx/platform/frameworks/support/+/androidx-master-dev:ui/ui-android-view/src/main/java/androidx/ui/androidview/ComposedView.kt still the best example on how to put an android view underneath a Compose component? When I tried using it I get: java.lang.IllegalStateException: Could not convert androidx.ui.androidview.AndroidViewHolder to an Emittable at androidx.compose.ViewApplyAdapter.end(ViewComposer.kt:119) at androidx.compose.Applier.up(Applier.kt:51) at androidx.compose.Composer$realizeSlots$12.invoke(Composer.kt:1377) ... at androidx.ui.material.DrawerKt.ModalDrawerLayout(Drawer.kt:113) at com.geeksville.mesh.ui.MeshAppKt$MeshApp$2.invoke(MeshApp.kt:160) at com.geeksville.mesh.ui.MeshAppKt$MeshApp$2.invoke(Unknown Source:3) at androidx.compose.AmbientKt.Providers(Ambient.kt:176) at androidx.ui.core.TextKt.CurrentTextStyleProvider(Text.kt:386) at androidx.ui.material.MaterialThemeKt$MaterialTheme$1$invoke$1.invoke(MaterialTheme.kt:92) at androidx.ui.material.MaterialThemeKt$MaterialTheme$1$invoke$1.invoke(Unknown Source:3) at androidx.compose.AmbientKt.Providers(Ambient.kt:176) at androidx.ui.material.MaterialThemeKt$MaterialTheme$1.invoke(MaterialTheme.kt:92) at androidx.ui.material.MaterialThemeKt$MaterialTheme$1.invoke(Unknown Source:3) at androidx.compose.AmbientKt.Providers(Ambient.kt:176) at androidx.ui.material.ColorKt.ProvideColorPalette(Color.kt:328) at androidx.ui.material.MaterialThemeKt.MaterialTheme(MaterialTheme.kt:92) at androidx.ui.material.MaterialThemeKt.MaterialTheme$default(MaterialTheme.kt:43) at com.geeksville.mesh.ui.MeshAppKt.MeshApp(MeshApp.kt:201) at com.geeksville.mesh.ui.MeshAppKt$MeshApp$5.invoke(Unknown Source:0) at com.geeksville.mesh.ui.MeshAppKt$MeshApp$5.invoke(Unknown Source:3) at androidx.compose.RecomposeScope.compose(Composer.kt:208) at androidx.compose.Composer.composeScope(Composer.kt:1239) at androidx.compose.Composer.recomposeComponentRange(Composer.kt:1185) at androidx.compose.Composer.skipCurrentGroup(Composer.kt:1234) at androidx.compose.Composer.recompose(Composer.kt:1303) at androidx.compose.Recomposer.performRecompose(Recomposer.kt:93) at androidx.compose.Recomposer.dispatchRecomposes(Recomposer.kt:119) at androidx.compose.AndroidRecomposer.access$dispatchRecomposes$1(Unknown Source:0) at androidx.compose.AndroidRecomposer$frameCallback$1.doFrame(AndroidRecomposer.kt:27) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:964) at android.view.Choreographer.doCallbacks(Choreographer.java:790) at android.view.Choreographer.doFrame(Choreographer.java:721)

I'm getting handleWindowVisibility: no activity for token android.os.BinderProxy, when trying to launch an activity within a compose activity. Is it possible to define a function that gets a composable function as a parameter and launches an activity that uses that function? This will allow to have modal windows that can be reused across the app. Like lets say edituser(id user)=launchactivity(composable userUI). Like having a helper activity just to display a modal window.

Please take a look at this function at jetpack compose sample: https://github.com/android/compose-samples/blob/master/JetNews/app/src/main/java/com/example/jetnews/ui/home/HomeScreen.kt#L97

@Composable
private fun HomeScreenTopSection(post: Post) {
    ProvideEmphasis(emphasis = EmphasisLevels().high) {
        Text(
            modifier = LayoutPadding(start = 16.dp, top = 16.dp, end = 16.dp, bottom = 0.dp),
            text = "Top stories for you",
            style = MaterialTheme.typography().subtitle1
        )
    }
    Ripple(bounded = true) {
        Clickable(onClick = {
            navigateTo(Screen.Article(post.id))
        }) {
            PostCardTop(post = post)
        }
    }
    HomeScreenDivider()
}

As you see it's an incomplete composable function because we are calling 3 other functions without a Row or Column, and

HomeScreenTopSection

can draw correctly just because the parent has called it inside a column: https://github.com/android/compose-samples/blob/master/JetNews/app/src/main/java/com/example/jetnews/ui/home/HomeScreen.kt#L88

Column(modifier = modifier) {
            HomeScreenTopSection(post = postTop)
            HomeScreenSimpleSection(posts = postsSimple)
            HomeScreenPopularSection(posts = postsPopular)
            HomeScreenHistorySection(posts = postsHistory)
        }

So if I call

HomeScreenTopSection

outside a column or row, there are multiple possible solutions: 1) the compose framework can decide to put it inside a Row for example 2) Keep the first one and throw away others and seems that compose follows this approach at the moment. 3) Threw error I think first and second solutions are not appropriate solutions and seems that throwing compile time error is not possible and just remains run time error. Our functions return Unit, if they return something the

HomeScreenTopSection

should return a list and the problem is solved we can throw compile time errors. but with returning functions we loose lots of its benefits so that's not an option here, but what about adding annotations like

ThisShouldBeCalledInsideRowOrColumn

(I know it's a worst naming you ever seen 😬) ?

I am trying to understand how focus works in CompseUI. Say I have 4 Textfields and I want the user to enter values then press the action key and move to the next one. Is there any example of what parts of compose UI to use for this?

Is there currently any support for specifying sizes/spaces as percentages of the parent component/available space? If not, is such support being considered for the future?

Is it possible to change TopAppBar's height without creating new one? it doesn't accept modifier and in source code the height is hardcoded

Surface(color = color, contentColor = contentColor, elevation = elevation, shape = shape) {
        Row(
            LayoutWidth.Fill + LayoutPadding(
                start = AppBarHorizontalPadding,
                end = AppBarHorizontalPadding
            ) + LayoutHeight(AppBarHeight),
            arrangement = Arrangement.SpaceBetween,
            children = children
        )
    }

I can't understand what is

Semantics

from the documentation: for example here:

Box(LayoutHeight.Fill + LayoutFlexible(1f), gravity = ContentGravity.BottomStart) {
            val baselineOffset = with(DensityAmbient.current) { TitleBaselineOffset.toDp() }
            AlignmentLineOffset(alignmentLine = LastBaseline, after = baselineOffset) {
                Semantics(container = true) {
                    CurrentTextStyleProvider(value = MaterialTheme.typography().h6) {
                        Row {
                            title()
                        }
                    }
                }
            }
        }

Can you please explain what is

Semantics

?

ClassCastException happened when sorting is made in DataTable of dev-06. Worked fine on dev-04. My composition function looks like this.

@Preview
@Composable
fun FullFeaturedTable() {
    val numbers = mutableListOf(1, 2, 100, 500)
    DataTable(
        columns = 1,
        sorting = DefaultDataTableSorting(
            sortableColumns = setOf(0),
            onSortRequest = { column , isAscending ->
                if (isAscending) {
                    numbers.sortBy { it }
                } else {
                    numbers.sortByDescending { it }
                }
            })
    ) {
        headerRow { Text(text = "Number") }

        for (number in numbers) {
            dataRow { Text("$number") }
        }
    }
}

Lin Min Phyo, your composition works fine on dev-06 (4.1-alpha02)

......
SetContent{
    ......
    FullFeaturedTable()
    ......
}
  


@Composable
fun FullFeaturedTable() {
    val numbers = mutableListOf(1, 2, 100, 500)
    DataTable(
        columns = 1,
        sorting = DefaultDataTableSorting(
            sortableColumns = setOf(0),
            onSortRequest = { column , isAscending ->
                if (isAscending) {
                    numbers.sortBy { it }
                } else {
                    numbers.sortByDescending { it }
                }
            })
    ) {
        headerRow { Text(text = "Number") }
        for (number in numbers) {
            dataRow { Text("$number") }
        }
    }
}

@Preview
@Composable
fun FeaturedTable() {
    FullFeaturedTable()
}

I am trying to use a two module setup for room and compose, but - eek I have errors during kaptGenerateStubsDebugKotlin :<(

Is there any way to print incoming constraints?

I'm playing with constraints to see how it works so I set the minWidth to

200.ipx

and MaxWidth to 300.ipx but the when I print the constraints minWidth is

0.ipx

, MaxWidth's value is 300.ipx as expected.

WithConstraints { constraints ->
        Log.d("Constraints", constraints.toString())
        with(DensityAmbient.current) {
            Container( modifier = LayoutWidth.Constrain(200.ipx.toDp(), 300.ipx.toDp())) {
                    WithConstraints { constraints2 ->
                        Log.d("Constraints2", constraints2.toString())
                        Column() {
                            Text("Test1")
                            Text("Test2")
                        }
                    }
                }
            }
        }

The log:

D/Constraints: Constraints(minWidth=0.ipx, maxWidth=800.ipx, minHeight=0.ipx, maxHeight=1173.ipx)

D/Constraints2: Constraints(minWidth=0.ipx, maxWidth=300.ipx, minHeight=0.ipx, maxHeight=1173.ipx)

Hi, I'd really like to be able to use my Model data classes in my junit tests. (where I'm not running under compose). Is there a way to prevent the following error in this case? java.lang.IllegalStateException: Not in a frame at androidx.compose.frames.FramesKt.currentFrame(Frames.kt:180) at androidx.compose.frames.FramesKt.readable(Frames.kt:448) at androidx.compose.frames.FramesKt._readable(Frames.kt:456) at com.geeksville.mesh.model.Channel.getSettings(UIState.kt) at com.geeksville.mesh.model.Channel.getChannelUrl(UIState.kt:60) at com.geeksville.mesh.model.ChannelTest.channelUrlGood(ChannelTest.kt:11) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50) ... at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)

I get

e: java.lang.NoSuchMethodError: org.jetbrains.kotlin.codegen.state.GenerationState$Builder.isIrBackend(Z)Lorg/jetbrains/kotlin/codegen/state/GenerationState$Builder;

Hello composer, I made a sample news app. I am using room, retrofit, livedata, viewmodel and compose dev-06. Please look into this project and any new idea or approach will be appreciated. https://github.com/amar1995/ModularNewsApp

I have a question about how to deal with state in an

AdapterList

. If I have actions in the individual row items that should update the view state, I’ve found that using a

MutableState

for the individual row views does not work. I’m guessing this is because even if the row view tries to set its state it still needs the state of the AdapterList to update in order to trigger the recomposition. My question then, is how should the state be updated for the

AdapterList

? In the

itemCallback

of

AdapterList

we only get the item passed to the lambda, not an index. Is it safe to grab the index of the item from within the

itemCallback

to update the list state?

I just updated to dev07 and tried to replace my custom RotateModifier with drawLayer modifier but realised that it does allow specifying the pivots points for the rotation. Will this be included in the next pre-alpha release?

I just tried to update to dev07 and my list example that worked perfectly okay in dev06 is now broken where I can see only 1 row of the list 😓

java.lang.NoSuchMethodError: No static method setContent(Landroid/app/Activity;Lkotlin/jvm/functions/Function0;)Landroidx/compose/Composition; in class Landroidx/ui/core/WrapperKt; or its super classes

Does anyone have any idea why this happens when calling setContent { }? I have tried: • 0.1.0-dev05, dev06 and dev07 • Kotlin 1.3.61 and 1.3.70 • with and without buildFeatures { compose true } and/or composeOptions

The

OnChildPositionedModifier

seems surprising to me. Given that a node can have any number of children, I'm glad the kdoc calls out that the callback will be invoked once for every child. But it would seem a lot more intuitive (and more consistent with the

Layout

composable) to invoke the callback once per layout pass, and instead pass in the list of

LayoutCoordinates

corresponding to all the children laid out in that pass. The current API makes it difficult to determine if two given callback invocations correspond to two siblings in the same pass or the same child in subsequent passes. What's the reasoning behind this API design?

Hi, what is the proper way to paint a Vectorial images in the version dev07?

I'm getting

java.lang.IllegalStateException: Couldn't find composer parameter

, any ideas? (stack trace in thread)

Another issue: I have an AdapterList and the scroll is very very slow in dev07. Any idea? Does anyone else have this problem?

Padding with negative values used to work before, now it crashes runtime (no compilation warnings given):

LayoutPadding(bottom = (-10).dp, end = (-5).dp)

Beyond the crash, what's the suggested way to achieve the same positioning?

(Draw)Image used to have

tint

parameter, which is gone now. I see

colorFilter

which needs a

BlendMode

beyond just passing the color. Looking at the possible values,

hue

is the one I guess I should use (commented "The effect is to tint the destination image with the source image."). To my disappointment this is how it looks:

hue(null), // Not Supported

Is there any other suitable replacement to achieve tinting the image?