migration from ActivityResult to Activity Result API

I'm new in programming, some technolgies i'm trying learn by myself, I've watched a lot of video new activity result Api, and i'm trying migrate in my project. everything fine , but trouble is the missing request code, what have to do or use for request code .

here in project old Activity result trying to Crop Image

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) { /// неед
        super.onActivityResult(requestCode, resultCode, data)
        if (resultCode == Activity.RESULT_OK) {
            if (requestCode == REQUEST_GALLERY) {
                data?.data.let {
                    if (it != null) {
                        imageUri = it
                        cropImage(it) }
                }

            } else if (requestCode == UCrop.REQUEST_CROP) {
                val resultUri = data?.let { UCrop.getOutput(it) }
                binding.image.loadUrl(resultUri.toString())
            }
        } else {
            toastMessage(requireContext(), getString(R.string.fail_download_image))
        }
    }

    private fun openGallery() {    /// галлерея
        val intent = Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI)
        startActivityForResult(intent, REQUEST_GALLERY)
    }

here I'm migrating Activirty Result Api

  val resultContract = registerForActivityResult(ActivityResultContracts.StartActivityForResult()){result: ActivityResult? ->
        if (result?.resultCode == Activity.RESULT_OK) {
            if (requestCode == REQUEST_GALLERY) {
                result.data?.data.let {
                    if (it != null) {
                        imageUri = it
                        cropImage(it) }
                }

            } else if (result.requestCode == UCrop.REQUEST_CROP) {
                val resultUri = result.data?.let { UCrop.getOutput(it) }
                binding.image.loadUrl(resultUri.toString())
            }
        } else {
            toastMessage(requireContext(), getString(R.string.fail_download_image))
        }

    }

here in Activity Result Api request code is unresolved references , what to use instead of request code???

I think I'm late with the answer. If you really need to get the request code in Activity Result API you should do something like that:

// You can use any request code
val REQUEST_GALLERY = 1001
val resultContract = registerForActivityResult(ActivityResultContracts.StartActivityForResult()){result: ActivityResult? ->
val requestCode = result.data?.extras?.getInt(REQUEST_GALLERY.toString())

if (result?.resultCode == Activity.RESULT_OK) {
        if (requestCode == REQUEST_GALLERY) {
            result.data?.data.let {
                if (it != null) {
                    imageUri = it
                    cropImage(it) }
            }

        } else if (result.requestCode == UCrop.REQUEST_CROP) {
            val resultUri = result.data?.let { UCrop.getOutput(it) }
            binding.image.loadUrl(resultUri.toString())
        }
    } else {
        toastMessage(requireContext(), getString(R.string.fail_download_image))
    }

}