Add scroll to bottom & unread chat message counter in chat room while scrolling up in history

CHANGELOG.md

@@ -22,6 +22,7 @@ Group changes to describe their impact on the project, as follows:
 
 ### Changed
 - UI has been reworked around SlidingPane component to better handle tablets & foldable devices
+- No longer scroll to bottom of chat room when new messages are received, a new button shows up to do it
 - Animations have been replaced to use com.google.android.material.transition ones
 - Using new [Unified Content API](https://developer.android.com/about/versions/12/features/unified-content-api) to share files from keyboard (or other sources)
 - Bumped dependencies, gradle updated from 4.2.2 to 7.0.2

app/src/main/java/org/linphone/activities/main/chat/ChatScrollListener.kt

@@ -29,6 +29,8 @@ internal abstract class ChatScrollListener(private val mLayoutManager: LinearLay
     // True if we are still waiting for the last set of data to load.
     private var loading = true
 
+    var userHasScrolledUp: Boolean = false
+
     // This happens many times a second during a scroll, so be wary of the code you place here.
     // We are given a few useful parameters to help us work out if we need to load some more data,
     // but first we check if we are waiting for the previous load to finish.
@@ -54,6 +56,13 @@ internal abstract class ChatScrollListener(private val mLayoutManager: LinearLay
             previousTotalItemCount = totalItemCount
         }
 
+        userHasScrolledUp = lastVisibleItemPosition != totalItemCount - 1
+        if (userHasScrolledUp) {
+            onScrolledUp()
+        } else {
+            onScrolledToEnd()
+        }
+
         // If it isn’t currently loading, we check to see if we have breached
         // the mVisibleThreshold and need to reload more data.
         // If we do need to reload some more data, we execute onLoadMore to fetch the data.
@@ -67,6 +76,12 @@ internal abstract class ChatScrollListener(private val mLayoutManager: LinearLay
     // Defines the process for actually loading more data based on page
     protected abstract fun onLoadMore(totalItemsCount: Int)
 
+    // Called when user has started to scroll up, opposed to onScrolledToEnd()
+    protected abstract fun onScrolledUp()
+
+    // Called when user has scrolled and reached the end of the items
+    protected abstract fun onScrolledToEnd()
+
     companion object {
         // The minimum amount of items to have below your current scroll position
         // before loading more.

app/src/main/java/org/linphone/activities/main/chat/fragments/DetailChatRoomFragment.kt

@@ -75,8 +75,15 @@ class DetailChatRoomFragment : MasterFragment<ChatRoomDetailFragmentBinding, Cha
         override fun onItemRangeInserted(positionStart: Int, itemCount: Int) {
             adapter.notifyItemChanged(positionStart - 1) // For grouping purposes
 
+            // Scroll to newly added messages automatically
             if (positionStart == adapter.itemCount - itemCount) {
-                scrollToBottom()
+                // But only if user hasn't initiated a scroll up in the messages history
+                if (viewModel.isUserScrollingUp.value == false) {
+                    scrollToBottom()
+                    viewModel.chatRoom.markAsRead()
+                } else {
+                    Log.w("[Chat Room] User has scrolled up manually in the messages history, don't scroll to the newly added message at the bottom & don't mark the chat room as read")
+                }
             }
         }
     }
@@ -191,10 +198,20 @@ class DetailChatRoomFragment : MasterFragment<ChatRoomDetailFragmentBinding, Cha
         RecyclerViewSwipeUtils(ItemTouchHelper.RIGHT, swipeConfiguration, swipeListener)
             .attachToRecyclerView(binding.chatMessagesList)*/
 
-        val chatScrollListener: ChatScrollListener = object : ChatScrollListener(layoutManager) {
+        val chatScrollListener = object : ChatScrollListener(layoutManager) {
             override fun onLoadMore(totalItemsCount: Int) {
                 listViewModel.loadMoreData(totalItemsCount)
             }
+
+            override fun onScrolledUp() {
+                viewModel.isUserScrollingUp.value = true
+            }
+
+            override fun onScrolledToEnd() {
+                viewModel.isUserScrollingUp.value = false
+                Log.i("[Chat Room] User has scrolled to the latest message, mark chat room as read")
+                viewModel.chatRoom.markAsRead()
+            }
         }
         binding.chatMessagesList.addOnScrollListener(chatScrollListener)
 
@@ -440,6 +457,10 @@ class DetailChatRoomFragment : MasterFragment<ChatRoomDetailFragmentBinding, Cha
             false
         }
 
+        binding.setScrollToBottomClickListener {
+            smoothScrollToPosition()
+        }
+
         if (textToShare?.isNotEmpty() == true) {
             Log.i("[Chat Room] Found text to share")
             chatSendingViewModel.textToSend.value = textToShare
@@ -715,6 +736,12 @@ class DetailChatRoomFragment : MasterFragment<ChatRoomDetailFragmentBinding, Cha
         }
     }
 
+    private fun smoothScrollToPosition() {
+        if (_adapter != null && adapter.itemCount > 0) {
+            binding.chatMessagesList.smoothScrollToPosition(adapter.itemCount - 1)
+        }
+    }
+
     private fun pickFile() {
         val intentsList = ArrayList<Intent>()
 

app/src/main/java/org/linphone/activities/main/chat/viewmodels/ChatMessagesListViewModel.kt

@@ -23,6 +23,7 @@ import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
 import java.util.*
+import kotlin.math.max
 import org.linphone.activities.main.chat.data.EventLogData
 import org.linphone.core.*
 import org.linphone.core.tools.Log
@@ -212,7 +213,10 @@ class ChatMessagesListViewModel(private val chatRoom: ChatRoom) : ViewModel() {
 
     private fun getEvents(): ArrayList<EventLogData> {
         val list = arrayListOf<EventLogData>()
-        val history = chatRoom.getHistoryEvents(MESSAGES_PER_PAGE)
+        val unreadCount = chatRoom.unreadMessagesCount
+        val loadCount = max(MESSAGES_PER_PAGE, unreadCount)
+        Log.i("[Chat Messages] $unreadCount unread messages in this chat room, loading $loadCount from history")
+        val history = chatRoom.getHistoryEvents(loadCount)
         for (eventLog in history) {
             list.add(EventLogData(eventLog))
         }

app/src/main/java/org/linphone/activities/main/chat/viewmodels/ChatRoomViewModel.kt

@@ -19,10 +19,13 @@
  */
 package org.linphone.activities.main.chat.viewmodels
 
+import android.animation.ValueAnimator
+import android.view.animation.LinearInterpolator
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
 import org.linphone.LinphoneApplication.Companion.coreContext
+import org.linphone.LinphoneApplication.Companion.corePreferences
 import org.linphone.R
 import org.linphone.contact.Contact
 import org.linphone.contact.ContactDataInterface
@@ -81,12 +84,29 @@ class ChatRoomViewModel(val chatRoom: ChatRoom) : ViewModel(), ContactDataInterf
         MutableLiveData<Boolean>()
     }
 
+    val isUserScrollingUp = MutableLiveData<Boolean>()
+
     var oneParticipantOneDevice: Boolean = false
 
     var addressToCall: Address? = null
 
     var onlyParticipantOnlyDeviceAddress: Address? = null
 
+    val chatUnreadCountTranslateY = MutableLiveData<Float>()
+
+    private val bounceAnimator: ValueAnimator by lazy {
+        ValueAnimator.ofFloat(AppUtils.getDimension(R.dimen.tabs_fragment_unread_count_bounce_offset), 0f).apply {
+            addUpdateListener {
+                val value = it.animatedValue as Float
+                chatUnreadCountTranslateY.value = value
+            }
+            interpolator = LinearInterpolator()
+            duration = 250
+            repeatMode = ValueAnimator.REVERSE
+            repeatCount = ValueAnimator.INFINITE
+        }
+    }
+
     private val contactsUpdatedListener = object : ContactsUpdatedListenerStub() {
         override fun onContactsUpdated() {
             Log.i("[Chat Room] Contacts have changed")
@@ -202,6 +222,8 @@ class ChatRoomViewModel(val chatRoom: ChatRoom) : ViewModel(), ContactDataInterf
 
         callInProgress.value = chatRoom.core.callsNb > 0
         updateRemotesComposing()
+
+        if (corePreferences.enableAnimations) bounceAnimator.start()
     }
 
     override fun onCleared() {
@@ -213,6 +235,7 @@ class ChatRoomViewModel(val chatRoom: ChatRoom) : ViewModel(), ContactDataInterf
         coreContext.contactsManager.removeListener(contactsUpdatedListener)
         chatRoom.removeListener(chatRoomListener)
         chatRoom.core.removeListener(coreListener)
+        if (corePreferences.enableAnimations) bounceAnimator.end()
     }
 
     fun hideMenu(): Boolean {

app/src/main/java/org/linphone/notifications/NotificationsManager.kt

@@ -142,8 +142,8 @@ class NotificationsManager(private val context: Context) {
             }
 
             if (currentlyDisplayedChatRoomAddress == room.peerAddress.asStringUriOnly()) {
-                Log.i("[Notifications Manager] Chat room is currently displayed, do not notify received message & mark it as read")
-                room.markAsRead()
+                Log.i("[Notifications Manager] Chat room is currently displayed, do not notify received message")
+                // Mark as read is now done in the DetailChatRoomFragment
                 return
             }
 

app/src/main/res/drawable/scroll_to_bottom.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:state_pressed="true">
+        <bitmap android:src="@drawable/scroll_to_bottom_default"
+            android:tint="?attr/drawableTintOverColor"/>
+    </item>
+    <item android:state_enabled="false">
+        <bitmap android:src="@drawable/scroll_to_bottom_default"
+            android:tint="?attr/drawableTintDisabledColor"/>
+    </item>
+    <item android:state_selected="true">
+        <bitmap android:src="@drawable/scroll_to_bottom_default"
+            android:tint="?attr/drawableTintOverColor"/>
+    </item>
+    <item>
+        <bitmap android:src="@drawable/scroll_to_bottom_default"
+            android:tint="?attr/drawableTintColor"/>
+    </item>
+</selector>
+

app/src/main/res/layout/chat_room_detail_fragment.xml

@@ -26,6 +26,9 @@
         <variable
             name="voiceRecordingTouchListener"
             type="android.view.View.OnTouchListener" />
+        <variable
+            name="scrollToBottomClickListener"
+            type="android.view.View.OnClickListener"/>
         <variable
             name="viewModel"
             type="org.linphone.activities.main.chat.viewmodels.ChatRoomViewModel" />
@@ -297,6 +300,38 @@
             android:layout_marginTop="8dp"
             android:layout_marginRight="8dp" />
 
+        <RelativeLayout
+            android:onClick="@{scrollToBottomClickListener}"
+            android:visibility="@{viewModel.isUserScrollingUp ? View.VISIBLE : View.GONE, default=gone}"
+            android:layout_width="50dp"
+            android:layout_height="50dp"
+            android:layout_marginEnd="5dp"
+            android:layout_marginBottom="10dp"
+            android:layout_above="@id/footer"
+            android:layout_alignParentEnd="true">
+
+            <ImageView
+                android:layout_width="40dp"
+                android:layout_height="40dp"
+                android:layout_alignParentStart="true"
+                android:layout_alignParentBottom="true"
+                android:background="@drawable/round_button_background"
+                android:padding="13dp"
+                android:src="@drawable/scroll_to_bottom" />
+
+            <TextView
+                style="@style/unread_count_font"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_alignParentTop="true"
+                android:layout_alignParentEnd="true"
+                android:background="@{viewModel.unreadMessagesCount == 0 ? @drawable/hidden_unread_message_count_bg : @drawable/unread_message_count_bg, default=@drawable/unread_message_count_bg}"
+                android:gravity="center"
+                android:text="@{viewModel.unreadMessagesCount == 0 ? `` : String.valueOf(viewModel.unreadMessagesCount), default=1}"
+                android:translationY="@{viewModel.chatUnreadCountTranslateY}" />
+
+        </RelativeLayout>
+
     </RelativeLayout>
 
 </layout>