Component used: Navigation
Version used: androidx.navigation:navigation-*:2.6.0 and above
Devices/Android versions reproduced on: Not applicable

This commit b1ac7d6 introduced a regression in how the title is dynamically rendered, and more precisely how the Bundle containing parameters is accessed.

Previously, it used the default Bundle.get(key) method:

if (argType == NavType.ReferenceType) {
    val value = context.resources.getString(arguments[argName] as Int)
    title.append(value)
} else {
    title.append(arguments[argName].toString())
}

But after this commit, it now uses Bundle.getString(key):

if (argType == NavType.ReferenceType) {
    val value = context.getString(bundle.getInt(argName))
    builder.append(value)
} else {
    builder.append(bundle.getString(argName))
}

Unfortunately, this breaks basic usage, with other types than String, since Bundle.getString(key) will return null.

Here is a very simple example:

<navigation>
    <fragment android:label="Album #{albumId}">
        <argument android:name="albumId" app:argType="long" />
    </fragment>
</navigation>

Previously it would have correctly set the title to "Album #42" (for example).
But since this update, it will render "Album #null"!