如何使用外部图中在嵌套图中声明的全局操作？

Question

我尝试使用带有嵌套图形的 Safe Args使用全局操作，但出现错误。

片段A.kt :

class FragmentA : Fragment() {
    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        return inflater.inflate(R.layout.fragment_a, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        btFragmentB.setOnClickListener {
            NavHostFragment.findNavController(this)
                .navigate(FragmentBDirections.actionGlobalFragmentB())
        }
    }
}

片段B.kt :

class FragmentB : Fragment()

主文件

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/main_nav_graph"
    app:startDestination="@id/fragmentA">

    <fragment
        android:id="@+id/fragmentA"
        android:name="com.cookpad.arcshowcase.stack.FragmentA"
        android:label="FragmentA" />

    <include app:graph="@navigation/fragment_b" />
</navigation>

片段_b.xml

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/fragment_b"
    app:startDestination="@id/fragmentB">
    <fragment
        android:id="@+id/fragmentB"
        android:name="com.cookpad.arcshowcase.stack.FragmentB"
        android:label="FragmentB" />
    <action
        android:id="@+id/action_global_fragmentB"
        app:destination="@id/fragmentB" />
</navigation>

当我运行这个时，我得到这个错误：java.lang.IllegalArgumentException: navigation destination com.cookpad.arc:id/action_global_fragmentB is unknown to this NavController这似乎表明 action_global_fragmentB 从未从子图中合并。

有没有办法使用从外部图中在嵌套图中声明的全局操作？

Answer 1

您只需将全局操作移至主图导航即可

主文件

<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/main_nav_graph"
    app:startDestination="@id/fragmentA">

    <fragment
        android:id="@+id/fragmentA"
        android:name="com.cookpad.arcshowcase.stack.FragmentA"
        android:label="FragmentA" />

    <include app:graph="@navigation/fragment_b" />

    <action
            android:id="@+id/action_global_fragmentB"
            app:destination="@id/fragment_b" />
        
</navigation>

片段_b.xml

<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/fragment_b"
    app:startDestination="@id/fragmentB">

    <fragment
        android:id="@+id/fragmentB"
        android:name="com.cookpad.arcshowcase.stack.FragmentB"
        android:label="FragmentB" /> 

</navigation>

片段A.kt

class FragmentA : Fragment() {
    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        return inflater.inflate(R.layout.fragment_a, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        btFragmentB.setOnClickListener {
            NavHostFragment.findNavController(this)
                .navigate(FragmentADirections.actionGlobalFragmentB())
        }
    }
}