如何通过在新类中移动代码（Kotlin）来避免 Android 中的意大利面条代码

Question

从下面的主类中，我试图将尽可能多的代码移动到 2 个分别名为“PhotoCapture.kt”和“PhotoUpload.kt”的新类文件中。我找不到让它工作的方法。看起来我只能在 MainActivity 中工作。例如，我找不到在新类中移动方法“onActivityResult”的方法。为了了解整个事情的运作方式，我还需要了解什么？

谢谢朋友们！

package com.tabapab.takepictureandsave

import android.content.Intent
import android.graphics.Bitmap
import android.graphics.BitmapFactory
import android.net.Uri
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.os.Environment
import android.provider.MediaStore
import android.support.v4.content.FileProvider
import android.util.Log
import android.util.Base64
import android.widget.ImageView
import com.android.volley.AuthFailureError
import com.android.volley.Request
import com.android.volley.Response
import com.android.volley.toolbox.StringRequest
import kotlinx.android.synthetic.main.activity_main.*
import org.json.JSONObject
import java.io.ByteArrayOutputStream
import java.io.File
import java.io.IOException
import java.text.SimpleDateFormat
import java.util.*


class MainActivity : AppCompatActivity() {
    var namaFile = ""
  //  var fileUri = Uri.parse("")
    val RC_CAMERA = 100

    val REQUEST_TAKE_PHOTO = 1001

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

        capture_btn.setOnClickListener {
            dispatchTakePictureIntent()
        }
    }

    private fun dispatchTakePictureIntent() {
        Intent(MediaStore.ACTION_IMAGE_CAPTURE).also { takePictureIntent ->
            // Ensure that there's a camera activity to handle the intent
            takePictureIntent.resolveActivity(packageManager)?.also {
                // Create the File where the photo should go
                val photoFile: File? = try {
                    createImageFile()
                } catch (ex: IOException) {
                    // Error occurred while creating the File

                    null
                }
                // Continue only if the File was successfully created
                photoFile?.also {
                    val photoURI: Uri = FileProvider.getUriForFile(
                            this,
                            "com.tabapab.takepictureandsave",
                            it
                    )
                    takePictureIntent.putExtra(MediaStore.ACTION_IMAGE_CAPTURE, photoURI)
                    takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI)
                    startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO)
                }
            }
        }
    }

    lateinit var currentPhotoPath: String

    @Throws(IOException::class)
    private fun createImageFile(): File {
        // Create an image file name
        val timeStamp: String = SimpleDateFormat("ddMMyyyy_HHmmss").format(Date())
        val storageDir: File = getExternalFilesDir(Environment.DIRECTORY_PICTURES)
        val filNam = File.createTempFile(
                "JPEG_${timeStamp}_", /* prefix */
                ".jpg", /* suffix */
                storageDir /* directory */
        ).apply {
            // Save a file: path for use with ACTION_VIEW intents
            currentPhotoPath = absolutePath
        }
        Log.d("myDebug", storageDir.toString())
        return filNam
    }


    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        if (requestCode == REQUEST_TAKE_PHOTO && resultCode == RESULT_OK) {
            //   val imageBitmap = data.extras.get("data") as Bitmap
            // image_view.setImageBitmap(imageBitmap)
            // galleryAddPic()
            val f = File(currentPhotoPath)
            Log.d("myDebug", currentPhotoPath)
       //     image_view.setImageURI(Uri.fromFile(f)) // this sets uncompressed,
        val imgStr =  getBitmapToString(image_view, Uri.fromFile(f))
            volleyImg(imgStr)
        }
    }

    fun bitmapToString(bmp: Bitmap): String {
        val outputStream = ByteArrayOutputStream()
        bmp.compress(Bitmap.CompressFormat.JPEG, 60, outputStream)
        val byteArray = outputStream.toByteArray()
        return Base64.encodeToString(byteArray, Base64.DEFAULT)


    }

    fun getBitmapToString(imV: ImageView, Fileuri: Uri): String {
            var bmp = Bitmap.createBitmap(100, 100, Bitmap.Config.ARGB_8888)
            bmp = BitmapFactory.decodeFile(Fileuri.path)
            Log.d("myDebug", Fileuri.path)
            var dim = 720
            Log.d("myDebug", "height:" + bmp.height + " _width:"+ bmp.width)
            if (bmp.height > bmp.width) {
                bmp = Bitmap.createScaledBitmap(bmp,
                        (bmp.width*dim).div(bmp.height), dim, true)
            } else {
                bmp = Bitmap.createScaledBitmap(bmp,
                        dim, (bmp.height*dim).div(bmp.width), true)
            }
            imV.setImageBitmap(bmp)
            return bitmapToString(bmp)
            return ""
    }

    private fun volleyImg(imgStr: String) {

        msg_display.text = "Starting Volley Kick"

        val url:String = "http://192.168.10.6/tabapad1/modules/android/classes/main.php?op=filestr"
        //      val rq:RequestQueue=Volley.newRequestQueue(this)
        val stringRequest = object : StringRequest(Request.Method.POST, url,
                Response.Listener<String> { response ->
                    // Process the json
                    try {
                        val obj = JSONObject(response)
                        msg_display.text = obj.getString("message")
                    } catch (e: Exception) {
                        msg_display.text = "Exception: $e"
                    }

                }, Response.ErrorListener { error ->
            msg_display.text = error.message
        }) {


            @Throws(AuthFailureError::class)
            override fun getParams(): Map<String, String> {
                val params = HashMap<String, String>()
                params.put("filename", "Maria2.jpg")
                params.put("imstr", imgStr)
                msg_display.text = "Sets the Volley parameters"
                return params

            }

        }
        // Add the volley post request to the request queue
        VolleySingleton.getInstance(this).addToRequestQueue(stringRequest)


        //    rq.add(request)


    }


//    private fun galleryAddPic() {
//        // run this to add the photo to system's Media Provider's database
//        // It will be available in the Android Gallery application and other Apps
//        Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE).also { mediaScanIntent ->
//            val f = File(currentPhotoPath)
//            mediaScanIntent.data = Uri.fromFile(f)
//            sendBroadcast(mediaScanIntent)
//        }
//    }


}

Answer 1

您不能将onActivityResult 移动为it's tied with startActivityForResult。您正在启动使用本机相机拍照的意图，并且您的活动正在期待结果。结果返回到最初启动意图的活动。

通常，您可以从活动中删除方法/功能，当它们的使用可以应用于其他各种地方时。例如，您的 bitmapToString 函数可以轻松放入 Utils 类中，因为它接收通用变量并且具有不依赖于活动的任何其他部分的主体。通过一些更改，也可以提取其他功能。例如，如果您将文件名变量作为参数添加到createImageFile()，您可以在其他活动中使用该变量，这些活动不一定希望与此处使用的文件名格式相同。