This is my Activity function that the startActivity(i) unable go to the Fragment page after scanning a barcode, I have try that it can go to activity page and show the code successful but I need it go to Fragment page.

barcodeDetector.setProcessor(object : Detector.Processor<Barcode> {

        override fun release() {
            Toast.makeText(applicationContext, "Scanner has been closed", Toast.LENGTH_SHORT)
                .show()
        }

        override fun receiveDetections(detections: Detector.Detections<Barcode>) {
            val barcodes = detections.detectedItems
            if (barcodes.size() == 1) {
                scannedValue = barcodes.valueAt(0).rawValue
                runOnUiThread {
                    cameraSource.stop()
                    Toast.makeText(this@InsertStockInActivity, scannedValue, Toast.LENGTH_SHORT).show()
                    val i = Intent(this@InsertStockInActivity, comFragment::class.java)
                    .putExtra("cameraSource", scannedValue)
                    startActivity(i)
                    finish()
                }
            }else
            {
                Toast.makeText(this@InsertStockInActivity, "value- else", Toast.LENGTH_SHORT).show()

            }
        }

    })

This is my Fragment page. do I write anything wrong?

 class comFragment : Fragment() {
       private lateinit var binding: FragmentComBinding
       private val nav by lazy { findNavController() }

       private val vm: StockInViewModel by activityViewModels()

       private val formatter = SimpleDateFormat("dd MMMM yyyy '-' hh:mm:ss a", Locale.getDefault())

       override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
       binding = FragmentComBinding.inflate(inflater, container, false)
       //binding.btnScanBarcode.setOnClickListener{ nav.navigate(R.id.insertStockInActivity) }

       val value = requireActivity().intent.getStringExtra("cameraSource")
       binding.edtId.findViewById<EditText>(R.id.value)

       return binding.root
   }

}

CodePudding user response：

You use intent to navigate to Activity not to Fragment.

You can:

1. Use fragment transactions to navigate to new Fragment in your current Activity

2. Use intent to navigate to new Activity and in your new Activity use fragment transactions to your Fragment

CodePudding user response：

You need to create a class that extends FragmentActivity and start your fragment there:

public class MyFragmentActivity extends YourActivity {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            if (savedInstanceState == null){
                getSupportFragmentManager().beginTransaction()
                        .add(android.R.id.content, new MyFragment ()).commit();}
        }
    }

then fragment constructor:

public MyFragment() {
}

then from your calling activity, start your fragment activity in the normal way

   Intent i = new Intent(YourActivity.this, MyFragment.class);
    startActivity(i);