I want to ask about an issue of DialogFragment. I ...

# compose

[Cash Hsiao]

I want to ask about an issue of DialogFragment. I create a DialogFragment using ComposeView which is normally work in alpha10:

class TestDialogFragment : DialogFragment() {
    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ) = ComposeView(requireContext()).apply {
        setContent {
            Surface {
                TestDialogLayout()
            }
        }
    }
}

It's all normal with the deploy Preview

@Preview
@Compose
fun PreviewTestDialog() {
    TestDialogLayout()
}

But when I navigate from other fragment like:

TestDialogFragment().show(childFragmentManager, "Test")

or navigation way:

findNavController().navigate(MainFragmentDirections.actionToTestDialog())

Both calls gave me this crash log:

java.lang.IllegalStateException: ViewTreeLifecycleOwner not found from DecorView@bec849f[MainActivity]
        at androidx.compose.ui.platform.WindowRecomposerKt.createLifecycleAwareViewTreeRecomposer(WindowRecomposer.kt:231)
        at androidx.compose.ui.platform.WindowRecomposerKt.access$createLifecycleAwareViewTreeRecomposer(WindowRecomposer.kt:1)
        at androidx.compose.ui.platform.WindowRecomposerFactory$Companion$LifecycleAware$1.createRecomposer(WindowRecomposer.kt:115)
        at androidx.compose.ui.platform.WindowRecomposerPolicy.createAndInstallWindowRecomposer$ui_release(WindowRecomposer.kt:168)
        at androidx.compose.ui.platform.WindowRecomposerKt.getWindowRecomposer(WindowRecomposer.kt:216)
        at androidx.compose.ui.platform.AbstractComposeView.ensureCompositionCreated(ComposeView.kt:184)
        at androidx.compose.ui.platform.AbstractComposeView.onAttachedToWindow(ComposeView.kt:215)
        at android.view.View.dispatchAttachedToWindow(View.java:19553)

I'm not sure what happened during the alpha10 to alpha12... anyone has idea?

[Vitor Prado]

you should be using appcompat 1.3.0-beta1

[Vitor Prado]

https://kotlinlang.slack.com/archives/CJLTWPH7S/p1613144837328700

[Vitor Prado]

see the thread above

[Ian Lake]

Dialogs (and specifically dialogs owned by DialogFragments) don't have the ViewTree APIs called on their decorView so you'd need to do that yourself. Do you mind filing an issue against Fragments so that we can do that for you? https://issuetracker.google.com/issues/new?component=460964&template=1182267

[Vitor Prado]

did you have and example of how to set ViewTreeLifecycle into decorView?

[Ian Lake]

ViewTreeLifecycleOwner.set(dialog.decorView, lifecycleOwner)

[Ian Lake]

Not sure when is the right time to call that though, I'd probably first try an OnShowListener

[Vitor Prado]

the decorView is my rootview?

[Vitor Prado]

this works for me:

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
    dialog?.window?.decorView?.let { 
        ViewTreeLifecycleOwner.set(it, viewLifecycleOwner)
    }
}

[Ian Lake]

Yep

[Cash Hsiao]

I've create the issue
https://issuetracker.google.com/issues/180691023
And setting ViewTreeLifecycleOwner at the beginning of onCreateView works fine! Thanks!
(BTW setting in OnShowListener is too late)

[Jeremy Woods]

We fixed this for DialogFragment earlier this week. You can try it out with snapshot buildId 7166224 to make sure your use case works.