Android Jetpack Navigation library and onActivityResult

问题

I'm trying to migrate an app to the new Navigation Architecture Component that was announced at GoogleIO'18

Suppose I need to use an activity that is normally started with startActivityForResult. This activity comes either from a library or a system activity, so I can't modify it.

Is there any way to include this activity as a destination in the navigation graph and get results from it?

回答1:

The only solution I have so far is to wrap that activity behind a fragment that catches the result and then presents it to the navigation graph:

class ScannerWrapperFragment : Fragment() {

    private val navController by lazy { NavHostFragment.findNavController(this) }

    override fun onResume() {
        super.onResume()
        // forward the call to ScannerActivity
        // do it in onResume to prevent call duplication from configuration changes
        val intent = Intent(context, ScannerActivity::class.java)
        startActivityForResult(intent, 4304357)
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        if (requestCode == 4304357) {
            if (resultCode == RESULT_OK) {

                val params = Bundle().apply {
                    putString("scan_result", data?.extras?.getString("scan_result"))
                }
                //present the scan results to the navigation graph
                navController.navigate(R.id.action_scanner_to_result_screen, params)

            } else {
                navController.popBackStack()
            }
        } else {
            super.onActivityResult(requestCode, resultCode, data)
        }

    }

}

来源：https://stackoverflow.com/questions/50488351/android-jetpack-navigation-library-and-onactivityresult