kotlin.UninitializedPropertyAccessException:lateinit属性roomClickedInterface尚未初始化 [英] kotlin.UninitializedPropertyAccessException: lateinit property roomClickedInterface has not been initialized
问题描述
我正在尝试针对建立小组"的Pusher Chatkit教程使用KOTLIN和PUSHER CHATKIT聊天应用程序" ，但是Recycler View适配器出现问题.仅供参考，我仍在学习Kotlin.我一直在阅读Lateinit vars，但是找不到任何可以解决这种情况的方法.该错误发生在回收站视图适配器中.
I am trying to follow Pusher Chatkit's tutorial for "BUILDING A GROUP CHAT APP USING KOTLIN AND PUSHER CHATKIT" however I am running into an issue with the Recycler View adapter. FYI, I am still learning Kotlin. I've been reading up on lateinit vars but I can't find anything that addresses this case. The error occurs in the recycler view adapter.
这是我得到的错误:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.android_myneighborsbookshelf, PID: 26692
kotlin.UninitializedPropertyAccessException: lateinit property roomClickedInterface has not been initialized
at com.example.android_myneighborsbookshelf.adapters.ChatRoomsListAdapter.getRoomClickedInterface(ChatRoomsListAdapter.kt:13)
at com.example.android_myneighborsbookshelf.adapters.ChatRoomsListAdapter$ViewHolder.onClick(ChatRoomsListAdapter.kt:66)
at android.view.View.performClick(View.java:6597)
at android.view.View.performClickInternal(View.java:6574)
at android.view.View.access$3100(View.java:778)
at android.view.View$PerformClick.run(View.java:25885)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
ChatRoomsListActivity.kt
class ChatRoomsListActivity : AppCompatActivity() {
val adapter = ChatRoomsListAdapter();
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_chat_room_list)
initRecyclerView()
initChatManager()
}
private fun initRecyclerView() {
recycler_view.layoutManager = LinearLayoutManager(this@ChatRoomsListActivity)
recycler_view.adapter = adapter
}
private fun initChatManager() {
val chatManager = ChatManager(
instanceLocator = "blahblahblah",
userId = "username1-PCKid",
dependencies = AndroidChatkitDependencies(
tokenProvider = ChatkitTokenProvider(
endpoint = "blahblahblah",
// endpoint = "http://10.0.2.2:3000/auth",
userId = "username1-PCKid"
)
)
)
chatManager.connect(listeners = ChatListeners(
onErrorOccurred = { },
onAddedToRoom = { },
onRemovedFromRoom = { },
onCurrentUserReceived = { },
onNewReadCursor = { },
onRoomDeleted = { },
onRoomUpdated = { },
onPresenceChanged = { u, n, p -> },
onUserJoinedRoom = { u, r -> },
onUserLeftRoom = { u, r -> },
onUserStartedTyping = { u, r -> },
onUserStoppedTyping = { u, r -> }
)) { result ->
when (result) {
is Result.Success -> {
// We have connected!
val currentUser = result.value
AppController.currentUser = currentUser
val userJoinedRooms = ArrayList<Room>(currentUser.rooms)
for (i in 0 until userJoinedRooms.size) {
adapter.addRoom(userJoinedRooms[i])
}
currentUser.getJoinableRooms { result ->
when (result) {
is Result.Success -> {
// Do something with List<Room>
val rooms = result.value
runOnUiThread {
for (i in 0 until rooms.size) {
adapter.addRoom(rooms[i])
}
}
}
}
}
adapter.setInterface(object : ChatRoomsListAdapter.RoomClickedInterface {
override fun roomSelected(room: Room) {
if (room.memberUserIds.contains(currentUser.id)) {
// user already belongs to this room
roomJoined(room)
} else {
currentUser.joinRoom(
roomId = room.id,
callback = { result ->
when (result) {
is Result.Success -> {
// Joined the room!
roomJoined(result.value)
}
is Result.Failure -> {
Log.d("TAG", result.error.toString())
}
}
}
)
}
}
})
}
is Result.Failure -> {
// Failure
Log.d("TAG", result.error.toString())
}
}
}
}
private fun roomJoined(room: Room) {
val intent = Intent(this@ChatRoomsListActivity, ChatRoomsListActivity::class.java)
intent.putExtra("room_id", room.id)
intent.putExtra("room_name", room.name)
startActivity(intent)
}
}
RecyclerView适配器
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import com.pusher.chatkit.rooms.Room
import android.view.LayoutInflater
import androidx.recyclerview.widget.RecyclerView
import com.example.android_myneighborsbookshelf.R
class ChatRoomsListAdapter: RecyclerView.Adapter<ChatRoomsListAdapter.ViewHolder>() {
private var list = ArrayList<Room>()
lateinit var roomClickedInterface:RoomClickedInterface // <-- Error occurs here - kt.13
fun addRoom(room:Room){
list.add(room)
notifyDataSetChanged()
}
fun setInterface(roomClickedInterface:RoomClickedInterface){
this.roomClickedInterface = roomClickedInterface
}
override fun getItemCount(): Int {
return list.size
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val view = LayoutInflater.from(parent.context)
.inflate(
android.R.layout.simple_list_item_1,
parent,
false
)
return ViewHolder(view)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.roomName.text = list[position].name
}
inner class ViewHolder(itemView: View): RecyclerView.ViewHolder(itemView), View.OnClickListener {
override fun onClick(p0: View?) {
roomClickedInterface.roomSelected(list[adapterPosition]) // <-- Error occurs here kt.66
}
var roomName: TextView = itemView.findViewById(android.R.id.text1)
init {
itemView.setOnClickListener(this)
}
}
interface RoomClickedInterface{
fun roomSelected(room:Room)
}
}
任何帮助都将受到赞赏.
Any and all help is appreciated.
推荐答案
lateinit表示延迟初始化.如果您不想初始化 构造函数中的一个变量，相反，您想稍后对其进行初始化 然后，如果您可以在使用前保证初始化，则 用lateinit关键字声明该变量.它不会分配 内存直到初始化.
lateinitmeans late initialization. If you do not want to initialize a variable in the constructor, instead you want to initialize it later on and if you can guarantee the initialization before using it, then declare that variable withlateinitkeyword. It will not allocate memory until initialized.
因此，您必须先初始化lateinit属性，然后才能使用它.
So, You have to initialize the lateinit property before try to use it.
选项-1:在单击列表项之前，调用setInterface()初始化属性.您还可以使用.isInitialized来检查lateinit变量是否已经初始化，如下所示:
Option - 1: Call setInterface() to initialize the property before click the list item. You can also check whether a lateinit var has already been initialized or not using .isInitialized like below:
override fun onClick(p0: View?) {
if(this::roomClickedInterface.isInitialized) {
roomClickedInterface.roomSelected(list[adapterPosition])
}
}
选项-2:从适配器及其设置器中删除lateinit属性
Option - 2: Remove lateinit property from your adapter and also it's setter
//lateinit var roomClickedInterface:RoomClickedInterface
并将RoomClickedInterface作为适配器的构造函数的参数传递
And pass RoomClickedInterface as parameter of your adapter's constructor
class ChatRoomsListAdapter(val roomClickedInterface:RoomClickedInterface):
RecyclerView.Adapter<ChatRoomsListAdapter.ViewHolder>() {
//Implementation
}
选项-3:删除lateinit并使用nullable属性
private var roomClickedInterface: RoomClickedInterface? = null
然后使用如下所示的方式使用null安全符号?.:
And then use like below using null safety notation ?.:
override fun onClick(p0: View?) {
roomClickedInterface?.roomSelected(list[adapterPosition])
}
这篇关于kotlin.UninitializedPropertyAccessException:lateinit属性roomClickedInterface尚未初始化的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
