Hi all, with the new safe args in compose navigation 2.8.0, I could not find a way to access the rei...

# compose-android

[alexhelder]

Hi all, with the new safe args in compose navigation 2.8.0, I could not find a way to access the reified T in the activity destination builder(kotlin DSL ), anyone know how?:

activity<Foo> {
  val foo:Foo = ?
  action = <http://foo.xxx|foo.xxx>
  data = <http://foo.xxx|foo.xxx>
}

[Ian Lake]

There is no instance of Foo when you are building the graph, so there is no instance to refer to at all here.

The way to extract information out of the class is via the dataPattern , which uses the {field} syntax to fill in part of the data with an argument from your class: https://developer.android.com/guide/navigation/design/activity-destinations#dynamic-arguments

[alexhelder]

Thanks Ian for the reply! If I understand, this app:dataPattern will work for Activities declared in my manifest, in general, how would I go about creating an activity<Foo> { } destination where the resolved Activity would be in another app?

[Ian Lake]

What makes you think the data pattern has any restrictions on what app is started?

[Ian Lake]

There's no such restriction at all - in fact, that same page actually specifically calls out that you need to set the targetPackage if you want to restrict it to only your own package

[alexhelder]

Ah, I got confused, thought this was a AndroidManifest xml block …

[alexhelder]

Ian BTW, the think you provided, both data and dataPattern links 404 for me https://developer.android.com/reference/androidx/navigation/ActivityNavigator.Destination%23setDataPattern(java.lang.String)

[Ian Lake]

They're linking to the right page for me, weird

[Ian Lake]

Ah, interesting, I do see an issue in an incognito window

[Ian Lake]

hopefully you figured out that you can just go to the ActivityNavigator.Destination page directly: https://developer.android.com/reference/androidx/navigation/ActivityNavigator.Destination

[alexhelder]

Ian are there any example snippets on how to use public inline fun <reified T : Any> NavGraphBuilder.activity anywhere, I still am confused about how to do

activity<Foo> {
    action = Intent.ACTION_VIEW
    data = something in Foo
}

[Ian Lake]

dataPattern = "<http://www.example.com/{name}|www.example.com/{name}>" where Foo has a field called name

[alexhelder]

OK Thanks Ian, I wound up with

fun NavGraphBuilder.viewLinkRoute() {
    activity<ViewLinkRoute> {
        action = Intent.ACTION_VIEW
        dataPattern = "{uri}"
    }
}

@Serializable
data class ViewLinkRoute(
    val uri: String
)

But get runtime exception No Activity found to handle Intent … just trying to do:

context.startActivity(
    Intent(Intent.ACTION_VIEW, uri)
)

but I’m getting closer. Thanks for your help so far.

[Ian Lake]

If you're really just trying to handle a generic Uri, I don't know why you are trying to use an activity destination at all. Generally you'd just use Compose's `LocalUriHandler`: https://developer.android.com/reference/kotlin/androidx/compose/ui/platform/package-summary?hl=en#LocalUriHandler() and call openUri on it

[alexhelder]

had no idea that existed, thanks!