科特林的registerForActivityResult和onActivityResult onActivityResult

Question

我目前正在尝试学习一步一步的教程，以上传图像或文件到我的服务器，同时使用截取。本教程有点过时，我真的不明白如何解决这些问题。

本教程

1. onActivityResult(Int, Int, Intent?): Unit' is deprecated. Deprecated in Java
2. Fragment is attempting to registerForActivityResult after being created. Fragments must call registerForActivityResult() before they are created (i.e. initialization, onAttach(), or onCreate()).

我的代码

//Uploading Photos
    private fun launchGallery() {
        val intent = Intent(Intent.ACTION_PICK)
        intent.type = "image/*"
        var resultLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
            if (result.resultCode == Activity.RESULT_OK) {
                // There are no request codes
                val data: Intent? = result.data
            }
        }
    }

    private fun uploadImage() {
        imageData?: return
        val request = object : VolleyFileUploadRequest(
            Request.Method.POST,
            postURL,
            {
                println("response is: $it")
            },
            {
                println("error is: $it")
            }
        ) {
            override fun getByteData(): MutableMap<String, FileDataPart> {
                var params = HashMap<String, FileDataPart>()
                params["imageFile"] = FileDataPart("image", imageData!!, "jpeg")
                return params
            }
        }
        Volley.newRequestQueue(requireContext()).add(request)
    }

    @Throws(IOException::class)
    private fun createImageData(uri: Uri) {
        val inputStream = requireContext().contentResolver.openInputStream(uri)
        inputStream?.buffered()?.use {
            imageData = it.readBytes()
        }
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        if (resultCode == Activity.RESULT_OK && requestCode == IMAGE_PICK_CODE) {
            val uri = data?.data
            if (uri != null) {
                imageView.setImageURI(uri)
                createImageData(uri)
            }
        }
        super.onActivityResult(requestCode, resultCode, data)
    }
}

Answer 1

您正在尝试从一个方法“registerForActivityResult ()”(这不是它应该做的方法)开始，"registerForActivityResult“应该在活动/片段onCreate函数中初始化，然后您可以使用"resultLauncher”变量来打开图片库/摄像机等等……

另外，当您使用"registerForActivityResult“时，您不需要覆盖"onActivityResult”(现在已不再推荐)。

检查活动结果以更好地理解新api的工作原理。

这里是一个很好的教程，它向您展示如何使用Android活动结果API来选择和拍摄图像。