android - 使用声明为 "intent.extras"对象的空变量初始化 "Bundle"

Question

初始化 b 时出现类型不匹配如 intent.extra .虽然 b类型为 Bundle?和 intent.extra不带null值以及 Bundle不能为空。

请为此问题提出解决方案。该应用程序在安装在 android 手机上并准备运行时不断崩溃。

代码正文中的以下代码 fragment 仅显示警告，但仅在启动时导致应用程序崩溃。

    import android.app.Activity
    import android.content.Context
    import android.content.Intent
    import android.graphics.Bitmap
    import android.graphics.BitmapFactory
    import android.graphics.drawable.BitmapDrawable
    import android.os.Bundle
    import android.provider.MediaStore
    import android.support.design.widget.Snackbar
    import android.support.design.widget.NavigationView
    import android.support.v4.view.GravityCompat
    import android.support.v7.app.ActionBarDrawerToggle
    import android.support.v7.app.AppCompatActivity
    import android.view.Menu
    import android.view.MenuItem
    import android.view.View
    import android.view.ViewGroup
    import android.widget.BaseAdapter
    import android.widget.Toast
    import com.example.debo.kickv01.R.id.lvTweets
    import kotlinx.android.synthetic.main.activity_navig.*
    import kotlinx.android.synthetic.main.app_bar_navig.*

    import com.example.debo.kickv01.saved
    import com.example.debo.kickv01.login as lg
    import com.google.firebase.auth.FirebaseAuth
    import com.google.firebase.database.FirebaseDatabase
    import com.google.firebase.storage.FirebaseStorage
    import kotlinx.android.synthetic.main.activity_login.*
    import kotlinx.android.synthetic.main.activity_saved.view.*
    import java.io.ByteArrayOutputStream
    import java.text.SimpleDateFormat
    import java.util.*

    class navig : AppCompatActivity(), NavigationView.OnNavigationItemSelectedListener {
        private var mAuth: FirebaseAuth?=null
        private var database= FirebaseDatabase.getInstance()
        private var myRef = database.reference

        var list_T=ArrayList<ticket>()
        var adaptor:MyPrjAdaptor?=null
        var UserUID:String?=null
        var myEmail:String?=null
        // var b:Bundle= intent.extras
        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
            setContentView(R.layout.activity_navig)
            val toolbar= null
            var b:Bundle = intent.extras
            myEmail = b.getString("email")
            UserUID = b.getString("uid")

            list_T.add(ticket("0","him","url","add"))
            list_T.add(ticket("0","him","url","debo"))
            list_T.add(ticket("0","him","url","debo_2"))

            adaptor=MyPrjAdaptor(this,list_T)
            lvTweets.adapter=adaptor

            fab.setOnClickListener { view ->
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show()
            }

            val toggle = ActionBarDrawerToggle(
                    this, drawer_layout, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close)
            drawer_layout.addDrawerListener(toggle)
            toggle.syncState()

            nav_view.setNavigationItemSelectedListener(this)
        }

        override fun onNavigationItemSelected(item: MenuItem): Boolean {
            // Handle navigation view item clicks here.
            when (item.itemId) {
                R.id.nav_home -> {
                    // Handle the camera action
                    var intent = Intent(this, navig::class.java)
                    startActivity(intent)
                }
                R.id.nav_explore -> {
                    var intent = Intent(this, explore::class.java)
                    startActivity(intent)
                }
                R.id.nav_Saved -> {
                    var intent = Intent(this, saved::class.java)
                    startActivity(intent)
                }
                R.id.nav_actions -> {
                    var intent = Intent(this, actions::class.java)
                    startActivity(intent)
                }
                R.id.nav_login -> {
                    var intent = Intent(this, com.example.debo.kickv01.login::class.java)
                    startActivity(intent)
                }
            }

            drawer_layout.closeDrawer(GravityCompat.START)
            return true
        }

        inner class MyPrjAdaptor: BaseAdapter{
            var listNotesAdaptor= ArrayList<ticket>()
            var context:Context?=null
            constructor(context: Context,listNotesAdaptor: ArrayList<ticket>):super(){
                this.listNotesAdaptor=listNotesAdaptor
                this.context=context
            }

            override fun getView(position: Int, convertView: View?, parent: ViewGroup?): View {
                var myTweet=listNotesAdaptor[position]

                if (myTweet.tweetPersonUID.equals("add")) {
                    var myView = layoutInflater.inflate(R.layout.activity_saved, null)
                    myView.etAttach.setOnClickListener {
                        loadImage()
                    }

                    myView.etPost.setOnClickListener {
                        myRef.child("posts").push().setValue(PostInfo(UserUID!!,
                                myView.etProject.text.toString(),
                                myView.etDescription.text.toString(),
                                DownloadURL!!))

                    }
                    return myView
                }else{
                    var myView = layoutInflater.inflate(R.layout.activity_explore, null)
                    return myView
                }
            }

            override fun getItem(position: Int): Any {
                return listNotesAdaptor[position]
            }

            override fun getItemId(position: Int): Long {
                return position.toLong()
            }

            override fun getCount(): Int {
                return listNotesAdaptor.size
            }
        }

        override fun onBackPressed() {
            if (drawer_layout.isDrawerOpen(GravityCompat.START)) {
                drawer_layout.closeDrawer(GravityCompat.START)
            } else {
                super.onBackPressed()
            }
        }

        override fun onCreateOptionsMenu(menu: Menu): Boolean {
            // Inflate the menu; this adds items to the action bar if it is present.
            menuInflater.inflate(R.menu.navig, menu)
            return true
        }

        override fun onOptionsItemSelected(item: MenuItem): Boolean {
            // Handle action bar item clicks here. The action bar will
            // automatically handle clicks on the Home/Up button, so long
            // as you specify a parent activity in AndroidManifest.xml.
            when (item.itemId) {
                R.id.action_settings -> return true
                else -> return super.onOptionsItemSelected(item)
            }
        }

        var PICK_IMAGE_CODE=123
        fun loadImage(){
            var intent=Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI)
            startActivityForResult(intent, PICK_IMAGE_CODE)
        }

        override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?)
        {
            super.onActivityResult(requestCode, resultCode, data)

            if(requestCode==PICK_IMAGE_CODE && resultCode== Activity.RESULT_OK && data!=null){
                val selectedImage=data.data
                val filePathColum = arrayOf(MediaStore.Images.Media.DATA)
                val cursor= contentResolver.query(selectedImage,filePathColum,null,null,null)
                cursor.moveToFirst()
                val columIndex= cursor.getColumnIndex(filePathColum[0])
                val picturepath= cursor.getString(columIndex)
                cursor.close()
                UploadImage(BitmapFactory.decodeFile(picturepath))
            }
        }

        var DownloadURL:String?=null
        fun UploadImage(bitmap: Bitmap){
            var currentUser= mAuth!!.currentUser

            val storage = FirebaseStorage.getInstance()
            val storageRef= storage.getReferenceFromUrl("gs://kick-13840.appspot.com")
            val df= SimpleDateFormat("ddMMyyHHmmss")
            val dataobj= Date()
            val imagePath= SplitString(myEmail!!) + "."+ df.format(dataobj)+ ".jpg"
            val ImageRef= storageRef.child("imagePost/"+imagePath)


            val baos= ByteArrayOutputStream()
            bitmap.compress(Bitmap.CompressFormat.JPEG,100,baos)
            val data=baos.toByteArray()
            val uploadTask=ImageRef.putBytes(data)
            uploadTask.addOnFailureListener{
                Toast.makeText(applicationContext,"fail to upload", Toast.LENGTH_LONG).show()

            }.addOnSuccessListener { taskSnapshot ->
                DownloadURL = taskSnapshot.storage.downloadUrl.toString()
            }
        }

        fun SplitString(email: String):String{
            val split= email.split("@")
            return split[0]
        }
    }

Answer 1

b 的类型为 Bundle而 intent.extras 返回 Bundle? ( Intent.getExtras() 用 @Nullable 注释，如果您查看它的代码)如 IDE 所示。您需要使用非空断言运算符 !! 或将 b 更改为类型 Bundle? .