Android Kotlin For Loop only runs once

Question

I'm having issues with my recycler view adapter. Only one item gets loaded to it being added from a for loop and i cant figure out why. All of my log statements indicate that numerous items are intended to be loaded but it stops loading after running once.

here is my log:

D/ChatRoomsListActivityTAG:: chatManager connected!
D/ChatRoomsListActivityTAG:: user: com.pusher.chatkit.CurrentUser@5f7cda6 is logged in to chatkit
D/ChatRoomsListActivityTAG:: joined rooms[Room(id=room 1577934249158, createdById=username1-PCKid, name=The Subtle Art of Not Giving a F*ck, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-02T03:04:10Z, updatedAt=2020-01-02T03:04:10Z, deletedAt=null), Room(id=my-room2, createdById=alice, name=my room2, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-01T20:48:29Z, updatedAt=2020-01-01T20:48:29Z, deletedAt=null), Room(id=room 1577934512686, createdById=username1-PCKid, name=The Subtle Art of Not Giving a F*ck, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-02T03:08:33Z, updatedAt=2020-01-02T03:08:33Z, deletedAt=null), Room(id=room 20200101-2041, createdById=username1-PCKid, name=The Subtle Art of Not Giving a F*ck, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-02T04:41:24Z, updatedAt=2020-01-02T04:41:24Z, deletedAt=null), Room(id=room 1577931826804, createdById=username1-PCKid, name=The Subtle Art of Not Giving a F*ck, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-02T02:23:48Z, updatedAt=2020-01-02T02:23:48Z, deletedAt=null), Room(id=room20200101-2045, createdById=username1-PCKid, name=The Subtle Art of Not Giving a F*ck, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-02T04:45:09Z, updatedAt=2020-01-02T04:45:09Z, deletedAt=null), Room(id=my-room, createdById=alice, name=my room, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=1, lastMessageAt=2020-01-10T05:44:08Z, createdAt=2020-01-01T20:44:39Z, updatedAt=2020-01-01T20:44:39Z, deletedAt=null)]
    joined rooms.size: 7
    adding room to adapter: Room(id=room 1577934249158, createdById=username1-PCKid, name=The Subtle Art of Not Giving a F*ck, pushNotificationTitleOverride=null, isPrivate=false, customData=null, unreadCount=0, lastMessageAt=null, createdAt=2020-01-02T03:04:10Z, updatedAt=2020-01-02T03:04:10Z, deletedAt=null)
    ForLoop .size:7

Here is my code: ChatListRoomsActivity.kt

chatManager.connect(listeners = ChatListeners(

        )
                , callback = { result ->
            when (result) {
                is Result.Success -> {
                    // We have connected!
                    Log.d(AppActivityTags.chatRoomsListActivityTAG, "chatManager connected!")
                    val currentUser = result.value
                    AppController.currentUser = currentUser
                    Log.d(AppActivityTags.chatRoomsListActivityTAG, "user: " + currentUser + " is logged in to chatkit")

                    val userJoinedRooms = ArrayList<Room>(currentUser.rooms)
                    Log.d(AppActivityTags.chatRoomsListActivityTAG, "joined rooms" + userJoinedRooms.toString());
                    Log.d(AppActivityTags.chatRoomsListActivityTAG, "joined rooms.size: " + userJoinedRooms.size.toString());


                    for (i in 0 until userJoinedRooms.size) { //<-- issue happens in this for loop
                        Log.d(AppActivityTags.chatRoomsListActivityTAG, "adding room to adapter: " + userJoinedRooms[i].toString()) // <-- logged to console
                        Log.d(AppActivityTags.chatRoomsListActivityTAG, "ForLoop .size: " + userJoinedRooms.size)  // <-- logged to console

                        adapter.addRoom(userJoinedRooms[i]) // <-- only 1 room is added to the adapter. There should be 7.
                        Log.d(AppActivityTags.chatRoomsListActivityTAG, "adding room to adapter: " + userJoinedRooms[i].toString()) // <-- never logged to console

                    }

                    adapter.setInterface(object : ChatRoomsListAdapter.RoomClickedInterface {
                        override fun roomSelected(room: Room) {
                            if (room.memberUserIds.contains(currentUser.id)) {
                                // user already belongs to this room
                                roomJoined(room)
                                Log.d("roomSelected", "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(AppActivityTags.chatRoomsListActivityTAG, "ChatManager connection failed"
                            + result.error.toString())
                }
            }
        })

ChatListRoomsAdapter.kt

package com.example.android_myneighborsbookshelf.adapters

import Chatkit.AppController.Companion.currentUser
import android.util.Log
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import com.pusher.chatkit.rooms.Room
import android.view.LayoutInflater
import android.widget.Toast
import androidx.recyclerview.widget.RecyclerView
import com.example.android_myneighborsbookshelf.AppActivityTags
import com.example.android_myneighborsbookshelf.R


class ChatRoomsListAdapter: RecyclerView.Adapter<ChatRoomsListAdapter.ViewHolder>() {
    private var list = ArrayList<Room>()
    private var roomClickedInterface: RoomClickedInterface? = null


    fun addRoom(room:Room){ //<-- this function is what is called in the activity
        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(
                        R.layout.chatroom_list_row,
                        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])
            Toast.makeText(itemView.context, "item was clicked", Toast.LENGTH_LONG).show();

            Log.d(AppActivityTags.chatRoomsListAdapterTAG, "Size of adapter: " + list.size.toString())
            for (x in currentUser.rooms) {
                Log.d(AppActivityTags.chatRoomsListAdapterTAG, x.toString())
            }

        }

        var roomName: TextView = itemView.findViewById(android.R.id.text1)

        init {
            itemView.setOnClickListener(this)

        }
    }

    interface RoomClickedInterface{
        fun roomSelected(room:Room)
    }
}

Direct pass the list of user in add room method then notify the adapter, if it is not worked then first print the latest size of list when you added new list in existing list.if size is more then one then tell me. — Avinash, Jan 10 '20 at 08:59
It's not possible for the last line in your for loop statement not to get called without your app crashing. Some detail is missing here. I don't see a problem with the code posted. Have you tried debugging and stepping through the loop? — Tenfour04, Jan 10 '20 at 14:36

score 0 · Answer 1 · answered Jan 10 '20 at 08:49

0

the for loop you are using is for (x in 0 until 10) println(x) // Prints 0 through 9 it will exclude 10 don't use this loop until you want to exclude any items, go thru the docs of kotlin before using anything use userJoinedRooms.forEach { adapter.addRoom(it) }

Hope this works

answered Jan 10 '20 at 08:49

Rakesh Rav

47
1
9

`until` is appropriate when creating a range for a collection, since it starts at 0. `for` is preferable to `forEach` because of clarity. `forEach` is really only provided for chained functional programming. In this case, the clearest loop would be `for (room in userJoinedRooms)`. – Tenfour04 Jan 10 '20 at 14:33
@Tenfour04 unfortunately neither of those methods work. it still only adds once to my adapter. – Cflux Jan 10 '20 at 14:53
1

@Cflux I was just pointing out where this advice could lead you down the wrong path. All of these have equivalent behavior. The source of your issue is elsewhere. – Tenfour04 Jan 10 '20 at 14:54

Android Kotlin For Loop only runs once

1 Answers1