片段创建的 Intent 不会触发 onNewIntent

Question

我正在开发一个使用 sdk 的应用程序，它利用 intent 在 sdk 和我的代码之间进行通信。在我的应用程序中，每当用户扫描条形码时，活动片段都会发送包含扫描意图的广播。 MainActivity class 解码此意图并通过共享视图模型将其发送回片段。

我目前面临的问题是我的 onNewIntent 从未被调用过。我尝试使用自定义函数手动处理它，但这似乎不是正确的方法（而且它似乎也不起作用）。我想要么我的意图有问题，要么我的视图模型运行不正常，或者可能是两者的结合。

class LoginFragment : Fragment() {
    private val intentViewModel by activityViewModels<IntentViewModel>()

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        val view = inflater.inflate(R.layout.fragment_login, container, false)
        val btnScanner = view.findViewById<Button>(R.id.btnScan)

        //If usercredentials get a value, that means the user has succesfully authenticated
        intentViewModel.userCredentials.observe(viewLifecycleOwner, Observer { credentials ->
            if (credentials[0] != "" && credentials[1] != "") {
             
                navigateToHome(intentViewModel.userCredentials.value!!)
            }
        })

        //Intent set by activity
        intentViewModel.intent.observe(viewLifecycleOwner, Observer { intent ->
            Timber.plant(Timber.DebugTree())
            val decodedData =
                intent!!.getStringExtra(
                    resources.getString(R.string.datawedge_intent_key_data)
                )
            //Never gets called --> intent never gets registered by activity
            Timber.d("Intent observer got called with value $decodedData")
            getUserCredentials(decodedData!!)
        })

        //Creates an intent based on motionevent, which gets broadcasted
        btnScanner.setOnTouchListener { v, motionEvent ->
            decodeEvent(v, motionEvent)
        }
        return view
    }
    
    //Hardcoded authentication example
    private fun getUserCredentials(badgeId: String) {
        var creds = Array(2) { "" }
        creds[0] = "12345678"
        creds[1] = "Logistics"
        intentViewModel.userCredentials.value = creds
    }

    private fun decodeEvent(v: View, motionEvent: MotionEvent): Boolean {
        if (motionEvent.action == MotionEvent.ACTION_DOWN) {
            //  Button pressed, start scan
            val dwIntent = Intent()
            dwIntent.action = "com.symbol.datawedge.api.ACTION"
            dwIntent.putExtra("com.symbol.datawedge.api.SOFT_SCAN_TRIGGER", "START_SCANNING")
            dwIntent.putExtra("Type", "START")
            activity?.sendBroadcast(dwIntent)
            //(activity as MainActivity).handleIntent(dwIntent)
        } else if (motionEvent.action == MotionEvent.ACTION_UP) {
            //  Button released, end scan
            val dwIntent = Intent()
            dwIntent.action = "com.symbol.datawedge.api.ACTION"
            dwIntent.putExtra("com.symbol.datawedge.api.SOFT_SCAN_TRIGGER", "STOP_SCANNING")
            dwIntent.putExtra("Type", "END")
            activity?.sendBroadcast(dwIntent)
            //  (activity as MainActivity).handleIntent(dwIntent)
        }
        return true
    }

    fun navigateToHome(userCredentials: Array<String>) {
        Navigation.findNavController(requireView())
            .navigate(LoginFragmentDirections.actionLoginFragmentToHomeFragment(userCredentials))
    }
}

class MainActivity : AppCompatActivity(){
    private val  intentViewModel by viewModels<IntentViewModel>()

    override fun onCreate( savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
    }

   //User scanned a barcode, which created an intent in the fragment
    override fun onNewIntent(intent: Intent) {
        super.onNewIntent(intent)
        intentViewModel.intent.value = intent
    }

}

class IntentViewModel: ViewModel() {
    var intent = MutableLiveData<Intent?>()
    var userCredentials = MutableLiveData<Array<String>>()
}

Answer 1

如果您在清单中将启动模式指定为“singleTop”activity，OnNewIntent 将会调用

片段创建的 Intent 不会触发 onNewIntent

Intent created by fragment does not trigger onNewIntent

android

android-intent

android-fragments

kotlin