使用声明为“Bundle”对象的空变量初始化“intent.extras”
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【中文标题】使用声明为“Bundle”对象的空变量初始化“intent.extras”【英文标题】：Initializing "intent.extras" with a null variable declared as "Bundle" object 【发布时间】：2019-04-08 17:26:32 【问题描述】：将b 初始化为intent.extra 时存在类型不匹配。虽然b 是Bundle? 类型，而intent.extra 不采用null 值，而且Bundle 也不能为空。
请为此问题提出解决方案。该应用程序在安装到 android 手机并准备运行时不断崩溃。
代码主体中的以下代码 sn-p 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]
【问题讨论】：
你试过private val bundle by lazy intent.extras 吗？
错误或问题是什么？
这个值 'bundle' 如何帮助将变量 'b' 变成一个非空对象。 @EpicPandaForce
哦，我刚刚将 b 重命名为 bundle，因为良好的编码习惯包括“不使用单字母变量名”（大部分时间）。
问题是“intent.extras”不采用空值，因为“b”是“捆绑？”对象“intent.extras”显示提示为“类型不匹配。必需：找到捆绑：捆绑？” -@AbhayKoradiya
【参考方案1】：
b 的类型为Bundle，而intent.extras 返回Bundle?（Intent.getExtras() 的注释为@Nullable，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 更改为键入 Bundle?。
【讨论】：
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