如何使用SavedStateHandle和导航安全参数

class MyViewModel(private val savedStateHandle: SavedStateHandle) : ViewModel() {
    // ...
}

class MyViewModel(private val savedStateHandle: SavedStateHandle) : ViewModel() {
    private val myData = savedStateHandle.getLiveData<String>("myData")

    fun setMyData(data: String) {
        myData.value = data
    }

    fun getMyData(): LiveData<String> {
        return myData
    }
}

class MyFragment : Fragment() {
    private val viewModel: MyViewModel by viewModels()

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

        viewModel.getMyData().observe(viewLifecycleOwner) { data ->
            // 使用SavedStateHandle中的数据
        }
    }
}

<fragment
    android:id="@+id/myFragment"
    android:name="com.example.MyFragment"
    android:label="My Fragment">
    <argument
        android:name="myArg"
        app:argType="string" />
</fragment>

val action = MyFragmentDirections.actionMyFragment()
action.setMyArg("Hello, World!")
findNavController().navigate(action)

val args: MyFragmentArgs by navArgs()
val myArg = args.myArg