IVS Chat Client Messaging SDK: Android Tutorial Part 2: Messages and Events - Amazon IVS

IVS Chat Client Messaging SDK: Android Tutorial Part 2: Messages and Events

This second (and last) part of the tutorial is broken up into several sections:

For full SDK documentation, start with Amazon IVS Chat Client Messaging SDK (here in the Amazon IVS Chat User Guide) and the Chat Client Messaging: SDK for Android Reference (on GitHub).

Prerequisite

Be sure you have completed Part 1 of this tutorial, Chat Rooms.

Create a UI for Sending Messages

Now that we successfully initialized the chat room connection, it’s time to send our first message. For this feature, a UI is needed. We will add:

  • connect/disconnect button

  • Message input with send button

  • Dynamic messages list. To build this, we use Android Jetpack RecyclerView.

UI Main Layout

See Android Jetpack Layouts in the Android developer documentation.

XML:

// ./app/src/main/res/layout/activity_main.xml <?xml version="1.0" encoding="utf-8"?> <androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent"> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/connect_view" android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center" android:orientation="vertical"> <androidx.cardview.widget.CardView android:id="@+id/connect_button" android:layout_width="match_parent" android:layout_height="48dp" android:layout_gravity="" android:layout_marginStart="16dp" android:layout_marginTop="4dp" android:layout_marginEnd="16dp" android:clickable="true" android:elevation="16dp" android:focusable="true" android:foreground="?android:attr/selectableItemBackground" app:cardBackgroundColor="@color/purple_500" app:cardCornerRadius="10dp"> <TextView android:id="@+id/connect_text" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentEnd="true" android:layout_gravity="center" android:layout_weight="1" android:paddingHorizontal="12dp" android:text="Connect" android:textColor="@color/white" android:textSize="16sp"/> <ProgressBar android:id="@+id/activity_indicator" android:layout_width="20dp" android:layout_height="20dp" android:layout_gravity="center" android:layout_marginHorizontal="20dp" android:indeterminateOnly="true" android:indeterminateTint="@color/white" android:indeterminateTintMode="src_atop" android:keepScreenOn="true" android:visibility="gone"/> </androidx.cardview.widget.CardView> </LinearLayout> <androidx.constraintlayout.widget.ConstraintLayout android:id="@+id/chat_view" android:layout_width="match_parent" android:layout_height="match_parent" android:clipToPadding="false" android:visibility="visible" tools:context=".MainActivity"> <RelativeLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" app:layout_constraintBottom_toTopOf="@+id/layout_message_input" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent"> <androidx.recyclerview.widget.RecyclerView android:id="@+id/recycler_view" android:layout_width="match_parent" android:layout_height="wrap_content" android:clipToPadding="false" android:paddingTop="70dp" android:paddingBottom="20dp"/> </RelativeLayout> <RelativeLayout android:id="@+id/layout_message_input" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@android:color/white" android:clipToPadding="false" android:drawableTop="@android:color/black" android:elevation="18dp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintStart_toStartOf="parent"> <EditText android:id="@+id/message_edit_text" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" android:layout_marginStart="16dp" android:layout_toStartOf="@+id/send_button" android:background="@android:color/transparent" android:hint="Enter Message" android:inputType="text" android:maxLines="6" tools:ignore="Autofill"/> <Button android:id="@+id/send_button" android:layout_width="84dp" android:layout_height="48dp" android:layout_alignParentEnd="true" android:background="@color/black" android:foreground="?android:attr/selectableItemBackground" android:text="Send" android:textColor="@color/white" android:textSize="12dp"/> </RelativeLayout> </androidx.constraintlayout.widget.ConstraintLayout> </androidx.coordinatorlayout.widget.CoordinatorLayout>

UI Abstracted Text Cell to Display Text Consistently

XML:

// ./app/src/main/res/layout/common_cell.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/layout_container" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@color/light_gray" android:minWidth="100dp" android:orientation="vertical"> <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal"> <TextView android:id="@+id/card_message_me_text_view" android:layout_width="wrap_content" android:layout_height="match_parent" android:layout_marginBottom="8dp" android:maxWidth="260dp" android:paddingLeft="12dp" android:paddingTop="8dp" android:paddingRight="12dp" android:text="This is a Message" android:textColor="#ffffff" android:textSize="16sp"/> <TextView android:id="@+id/failed_mark" android:layout_width="40dp" android:layout_height="match_parent" android:paddingRight="5dp" android:src="@drawable/ic_launcher_background" android:text="!" android:textAlignment="viewEnd" android:textColor="@color/white" android:textSize="25dp" android:visibility="gone"/> </LinearLayout> </LinearLayout>

UI Left Chat Message

XML:

// ./app/src/main/res/layout/card_view_left.xml <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginStart="8dp" android:layout_marginBottom="12dp" android:orientation="vertical"> <TextView android:id="@+id/username_edit_text" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="UserName"/> <androidx.constraintlayout.widget.ConstraintLayout android:layout_width="match_parent" android:layout_height="wrap_content"> <androidx.cardview.widget.CardView android:id="@+id/card_message_other" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="left" android:layout_marginBottom="4dp" android:foreground="?android:attr/selectableItemBackground" app:cardBackgroundColor="@color/light_gray_2" app:cardCornerRadius="10dp" app:cardElevation="0dp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintStart_toStartOf="parent"> <include layout="@layout/common_cell"/> </androidx.cardview.widget.CardView> <TextView android:id="@+id/dateText" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="4dp" android:layout_marginBottom="4dp" android:text="10:00" app:layout_constraintBottom_toBottomOf="@+id/card_message_other" app:layout_constraintLeft_toRightOf="@+id/card_message_other"/> </androidx.constraintlayout.widget.ConstraintLayout> </LinearLayout>

UI Right Chat Message

XML:

// ./app/src/main/res/layout/card_view_right.xml <?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginEnd="8dp"> <androidx.cardview.widget.CardView android:id="@+id/card_message_me" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="right" android:layout_marginBottom="10dp" android:foreground="?android:attr/selectableItemBackground" app:cardBackgroundColor="@color/purple_500" app:cardCornerRadius="10dp" app:cardElevation="0dp" app:cardPreventCornerOverlap="false" app:cardUseCompatPadding="true" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintEnd_toEndOf="parent"> <include layout="@layout/common_cell"/> </androidx.cardview.widget.CardView> <TextView android:id="@+id/dateText" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginRight="12dp" android:layout_marginBottom="4dp" android:text="10:00" app:layout_constraintBottom_toBottomOf="@+id/card_message_me" app:layout_constraintRight_toLeftOf="@+id/card_message_me"/> </androidx.constraintlayout.widget.ConstraintLayout>

UI Additional Color Values

XML:

// ./app/src/main/res/values/colors.xml <?xml version="1.0" encoding="utf-8"?> <resources> <!-- ...--> <color name="dark_gray">#4F4F4F</color> <color name="blue">#186ED3</color> <color name="dark_red">#b30000</color> <color name="light_gray">#B7B7B7</color> <color name="light_gray_2">#eef1f6</color> </resources>

Apply View Binding

We leverage the Android View Binding feature to be able to reference binding classes for our XML layout. To enable the feature, set the viewBinding build option to true in ./app/build.gradle:

Kotlin Script:

// ./app/build.gradle android { // ... buildFeatures { viewBinding = true } // ... }

Now it's time to connect the UI with our Kotlin code:

Kotlin:

// ./app/src/main/java/com/chatterbox/myapp/MainActivity.kt package com.chatterbox.myapp // ... const val TAG = "Chatterbox-MyApp" class MainActivity : AppCompatActivity() { // ... private fun sendMessage(request: SendMessageRequest) { try { room?.sendMessage( request, object : SendMessageCallback { override fun onRejected(request: SendMessageRequest, error: ChatError) { runOnUiThread { entries.addFailedRequest(request) scrollToBottom() Log.e(TAG, "Message rejected: ${error.errorMessage}") } } } ) entries.addPendingRequest(request) binding.messageEditText.text.clear() scrollToBottom() } catch (error: Exception) { Log.e(TAG, error.message ?: "Unknown error occurred") } } private fun scrollToBottom() { binding.recyclerView.smoothScrollToPosition(entries.size - 1) } private fun sendButtonClick(view: View) { val content = binding.messageEditText.text.toString() if (content.trim().isEmpty()) { return } val request = SendMessageRequest(content) sendMessage(request) } }

We also add methods to delete messages and disconnect users from the chat, which can be invoked using the chat-message context menu:

Kotlin:

// ./app/src/main/java/com/chatterbox/myapp/MainActivity.kt package com.chatterbox.myapp // ... class MainActivity : AppCompatActivity() { // ... private fun deleteMessage(request: DeleteMessageRequest) { room?.deleteMessage( request, object : DeleteMessageCallback { override fun onRejected(request: DeleteMessageRequest, error: ChatError) { runOnUiThread { Log.d(TAG, "Delete message rejected: ${error.errorMessage}") } } } ) } private fun disconnectUser(request: DisconnectUserRequest) { room?.disconnectUser( request, object : DisconnectUserCallback { override fun onRejected(request: DisconnectUserRequest, error: ChatError) { runOnUiThread { Log.d(TAG, "Disconnect user rejected: ${error.errorMessage}") } } } ) } }

Manage Chat-Message Requests

We need a way to manage our chat-message requests through all their possible states:

  • Pending β€” A message was sent to a chat room but is not yet confirmed or rejected.

  • Confirmed β€” A message was sent by the chat room to all users (including us).

  • Rejected β€” A message was rejected by the chat room with an error object.

We will keep unresolved chat requests and chat messages in a list. The list merits a separate class, which we call ChatEntries.kt:

Kotlin:

// ./app/src/main/java/com/chatterbox/myapp/ChatEntries.kt package com.chatterbox.myapp import com.amazonaws.ivs.chat.messaging.entities.ChatMessage import com.amazonaws.ivs.chat.messaging.requests.SendMessageRequest sealed class ChatEntry() { class Message(val message: ChatMessage) : ChatEntry() class PendingRequest(val request: SendMessageRequest) : ChatEntry() class FailedRequest(val request: SendMessageRequest) : ChatEntry() } class ChatEntries { /* This list is kept in sorted order. ChatMessages are sorted by date, while pending and failed requests are kept in their original insertion point. */ val entries = mutableListOf<ChatEntry>() var adapter: ChatListAdapter? = null val size get() = entries.size /** * Insert pending request at the end. */ fun addPendingRequest(request: SendMessageRequest) { val insertIndex = entries.size entries.add(insertIndex, ChatEntry.PendingRequest(request)) adapter?.notifyItemInserted(insertIndex) } /** * Insert received message at proper place based on sendTime. This can cause removal of pending requests. */ fun addReceivedMessage(message: ChatMessage) { /* Skip if we have already handled that message. */ val existingIndex = entries.indexOfLast { it is ChatEntry.Message && it.message.id == message.id } if (existingIndex != -1) { return } val removeIndex = entries.indexOfLast { it is ChatEntry.PendingRequest && it.request.requestId == message.requestId } if (removeIndex != -1) { entries.removeAt(removeIndex) } val insertIndexRaw = entries.indexOfFirst { it is ChatEntry.Message && it.message.sendTime > message.sendTime } val insertIndex = if (insertIndexRaw == -1) entries.size else insertIndexRaw entries.add(insertIndex, ChatEntry.Message(message)) if (removeIndex == -1) { adapter?.notifyItemInserted(insertIndex) } else if (removeIndex == insertIndex) { adapter?.notifyItemChanged(insertIndex) } else { adapter?.notifyItemRemoved(removeIndex) adapter?.notifyItemInserted(insertIndex) } } fun addFailedRequest(request: SendMessageRequest) { val removeIndex = entries.indexOfLast { it is ChatEntry.PendingRequest && it.request.requestId == request.requestId } if (removeIndex != -1) { entries.removeAt(removeIndex) entries.add(removeIndex, ChatEntry.FailedRequest(request)) adapter?.notifyItemChanged(removeIndex) } else { val insertIndex = entries.size entries.add(insertIndex, ChatEntry.FailedRequest(request)) adapter?.notifyItemInserted(insertIndex) } } fun removeMessage(messageId: String) { val removeIndex = entries.indexOfFirst { it is ChatEntry.Message && it.message.id == messageId } entries.removeAt(removeIndex) adapter?.notifyItemRemoved(removeIndex) } fun removeFailedRequest(requestId: String) { val removeIndex = entries.indexOfFirst { it is ChatEntry.FailedRequest && it.request.requestId == requestId } entries.removeAt(removeIndex) adapter?.notifyItemRemoved(removeIndex) } fun removeAll() { entries.clear() } }

To connect our list with the UI, we use an Adapter. For more information, see Binding to Data with AdapterView and Generated binding classes.

Kotlin:

// ./app/src/main/java/com/chatterbox/myapp/ChatListAdapter.kt package com.chatterbox.myapp import android.content.Context import android.graphics.Color import android.view.LayoutInflater import android.view.View import android.view.ViewGroup import android.widget.LinearLayout import android.widget.TextView import androidx.core.content.ContextCompat import androidx.core.view.isGone import androidx.recyclerview.widget.RecyclerView import com.amazonaws.ivs.chat.messaging.requests.DisconnectUserRequest import java.text.DateFormat class ChatListAdapter( private val entries: ChatEntries, private val onDisconnectUser: (request: DisconnectUserRequest) -> Unit, ) : RecyclerView.Adapter<ChatListAdapter.ViewHolder>() { var context: Context? = null var userId: String? = null class ViewHolder(view: View) : RecyclerView.ViewHolder(view) { val container: LinearLayout = view.findViewById(R.id.layout_container) val textView: TextView = view.findViewById(R.id.card_message_me_text_view) val failedMark: TextView = view.findViewById(R.id.failed_mark) val userNameText: TextView? = view.findViewById(R.id.username_edit_text) val dateText: TextView? = view.findViewById(R.id.dateText) } override fun onCreateViewHolder(viewGroup: ViewGroup, viewType: Int): ViewHolder { if (viewType == 0) { val rightView = LayoutInflater.from(viewGroup.context).inflate(R.layout.card_view_right, viewGroup, false) return ViewHolder(rightView) } val leftView = LayoutInflater.from(viewGroup.context).inflate(R.layout.card_view_left, viewGroup, false) return ViewHolder(leftView) } override fun getItemViewType(position: Int): Int { // Int 0 indicates to my message while Int 1 to other message val chatMessage = entries.entries[position] return if (chatMessage is ChatEntry.Message && chatMessage.message.sender.userId != userId) 1 else 0 } override fun onBindViewHolder(viewHolder: ViewHolder, position: Int) { return when (val entry = entries.entries[position]) { is ChatEntry.Message -> { viewHolder.textView.text = entry.message.content val bgColor = if (entry.message.sender.userId == userId) { R.color.purple_500 } else { R.color.light_gray_2 } viewHolder.container.setBackgroundColor(ContextCompat.getColor(context!!, bgColor)) if (entry.message.sender.userId != userId) { viewHolder.textView.setTextColor(Color.parseColor("#000000")) } viewHolder.failedMark.isGone = true viewHolder.itemView.setOnCreateContextMenuListener { menu, _, _ -> menu.add("Kick out").setOnMenuItemClickListener { val request = DisconnectUserRequest(entry.message.sender.userId, "Some reason") onDisconnectUser(request) true } } viewHolder.userNameText?.text = entry.message.sender.userId viewHolder.dateText?.text = DateFormat.getTimeInstance(DateFormat.SHORT).format(entry.message.sendTime) } is ChatEntry.PendingRequest -> { viewHolder.container.setBackgroundColor(ContextCompat.getColor(context!!, R.color.light_gray)) viewHolder.textView.text = entry.request.content viewHolder.failedMark.isGone = true viewHolder.itemView.setOnCreateContextMenuListener(null) viewHolder.dateText?.text = "Sending" } is ChatEntry.FailedRequest -> { viewHolder.textView.text = entry.request.content viewHolder.container.setBackgroundColor(ContextCompat.getColor(context!!, R.color.dark_red)) viewHolder.failedMark.isGone = false viewHolder.dateText?.text = "Failed" } } } override fun onAttachedToRecyclerView(recyclerView: RecyclerView) { super.onAttachedToRecyclerView(recyclerView) context = recyclerView.context } override fun getItemCount() = entries.entries.size }

Final Steps

It is time to hook up our new adapter, binding ChatEntries class to MainActivity:

Kotlin:

// ./app/src/main/java/com/chatterbox/myapp/MainActivity.kt package com.chatterbox.myapp // ... import com.chatterbox.myapp.databinding.ActivityMainBinding import com.chatterbox.myapp.ChatListAdapter import com.chatterbox.myapp.ChatEntries class MainActivity : AppCompatActivity() { // ... private var entries = ChatEntries() private lateinit var adapter: ChatListAdapter private lateinit var binding: ActivityMainBinding /* see https://developer.android.com/topic/libraries/data-binding/generated-binding#create */ override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) binding = ActivityMainBinding.inflate(layoutInflater) setContentView(binding.root) /* Create room instance. */ room = ChatRoom(REGION, ::fetchChatToken).apply { listener = roomListener } binding.sendButton.setOnClickListener(::sendButtonClick) binding.connectButton.setOnClickListener { connect() } setUpChatView() updateConnectionState(ConnectionState.DISCONNECTED) } private fun setUpChatView() { /* Setup Android Jetpack RecyclerView - see https://developer.android.com/develop/ui/views/layout/recyclerview.*/ adapter = ChatListAdapter(entries, ::disconnectUser) entries.adapter = adapter val recyclerViewLayoutManager = LinearLayoutManager(this@MainActivity, LinearLayoutManager.VERTICAL, false) binding.recyclerView.layoutManager = recyclerViewLayoutManager binding.recyclerView.adapter = adapter binding.sendButton.setOnClickListener(::sendButtonClick) binding.messageEditText.setOnEditorActionListener { _, _, event -> val isEnterDown = (event.action == KeyEvent.ACTION_DOWN) && (event.keyCode == KeyEvent.KEYCODE_ENTER) if (!isEnterDown) { return@setOnEditorActionListener false } sendButtonClick(binding.sendButton) return@setOnEditorActionListener true } } }

As we already have a class responsible for keeping track of our chat requests (ChatEntries), we are ready to implement code for manipulating entries in roomListener. We will update entries and connectionState accordingly to the event we are responding to:

Kotlin:

// ./app/src/main/java/com/chatterbox/myapp/MainActivity.kt package com.chatterbox.myapp // ... class MainActivity : AppCompatActivity() { //... private fun sendMessage(request: SendMessageRequest) { //... } private fun scrollToBottom() { binding.recyclerView.smoothScrollToPosition(entries.size - 1) } private val roomListener = object : ChatRoomListener { override fun onConnecting(room: ChatRoom) { Log.d(TAG, "[${Thread.currentThread().name}] onConnecting") runOnUiThread { updateConnectionState(ConnectionState.LOADING) } } override fun onConnected(room: ChatRoom) { Log.d(TAG, "[${Thread.currentThread().name}] onConnected") runOnUiThread { updateConnectionState(ConnectionState.CONNECTED) } } override fun onDisconnected(room: ChatRoom, reason: DisconnectReason) { Log.d(TAG, "[${Thread.currentThread().name}] onDisconnected") runOnUiThread { updateConnectionState(ConnectionState.DISCONNECTED) entries.removeAll() } } override fun onMessageReceived(room: ChatRoom, message: ChatMessage) { Log.d(TAG, "[${Thread.currentThread().name}] onMessageReceived $message") runOnUiThread { entries.addReceivedMessage(message) scrollToBottom() } } override fun onEventReceived(room: ChatRoom, event: ChatEvent) { Log.d(TAG, "[${Thread.currentThread().name}] onEventReceived $event") } override fun onMessageDeleted(room: ChatRoom, event: DeleteMessageEvent) { Log.d(TAG, "[${Thread.currentThread().name}] onMessageDeleted $event") } override fun onUserDisconnected(room: ChatRoom, event: DisconnectUserEvent) { Log.d(TAG, "[${Thread.currentThread().name}] onUserDisconnected $event") } } }

Now you should be able to run your application! (See Build and run your app.) Remember to have your backend server running when using the app. You can spin it up from the terminal at the root of our project with this command: ./gradlew :auth-server:run or by executing the auth-server:run Gradle task directly from Android Studio.