Use DiffUtil at conversations screen

app/src/main/kotlin/com/simplemobiletools/smsmessenger/activities/MainActivity.kt

@@ -299,7 +299,7 @@ class MainActivity : SimpleActivity() {
         val currAdapter = conversations_list.adapter
         if (currAdapter == null) {
             hideKeyboard()
-            ConversationsAdapter(this, sortedConversations, conversations_list) {
+            ConversationsAdapter(this, conversations_list) {
                 Intent(this, ThreadActivity::class.java).apply {
                     val conversation = it as Conversation
                     putExtra(THREAD_ID, conversation.threadId)
@@ -308,6 +308,7 @@ class MainActivity : SimpleActivity() {
                 }
             }.apply {
                 conversations_list.adapter = this
+                updateConversations(sortedConversations)
             }
 
             if (areSystemAnimationsEnabled) {
@@ -315,13 +316,14 @@ class MainActivity : SimpleActivity() {
             }
         } else {
             try {
-                (currAdapter as ConversationsAdapter).updateConversations(sortedConversations)
+                (currAdapter as ConversationsAdapter).updateConversations(sortedConversations) {
-                if (currAdapter.conversations.isEmpty()) {
+                    if (currAdapter.currentList.isEmpty()) {
                         conversations_fastscroller.beGone()
                         no_conversations_placeholder.text = getString(R.string.no_conversations_found)
                         no_conversations_placeholder.beVisible()
                         no_conversations_placeholder_2.beVisible()
                     }
+                }
             } catch (ignored: Exception) {
             }
         }

app/src/main/kotlin/com/simplemobiletools/smsmessenger/adapters/ConversationsAdapter.kt

@@ -2,15 +2,18 @@ package com.simplemobiletools.smsmessenger.adapters
 
 import android.content.Intent
 import android.graphics.Typeface
+import android.os.Parcelable
 import android.text.TextUtils
 import android.util.TypedValue
 import android.view.Menu
 import android.view.View
 import android.view.ViewGroup
 import android.widget.TextView
+import androidx.recyclerview.widget.DiffUtil
+import androidx.recyclerview.widget.RecyclerView
 import com.bumptech.glide.Glide
 import com.qtalk.recyclerviewfastscroller.RecyclerViewFastScroller
-import com.simplemobiletools.commons.adapters.MyRecyclerViewAdapter
+import com.simplemobiletools.commons.adapters.MyRecyclerViewListAdapter
 import com.simplemobiletools.commons.dialogs.ConfirmationDialog
 import com.simplemobiletools.commons.extensions.*
 import com.simplemobiletools.commons.helpers.KEY_PHONE
@@ -26,14 +29,23 @@ import com.simplemobiletools.smsmessenger.models.Conversation
 import kotlinx.android.synthetic.main.item_conversation.view.*
 
 class ConversationsAdapter(
-    activity: SimpleActivity, var conversations: ArrayList<Conversation>, recyclerView: MyRecyclerView, itemClick: (Any) -> Unit
+    activity: SimpleActivity, recyclerView: MyRecyclerView, itemClick: (Any) -> Unit
-) : MyRecyclerViewAdapter(activity, recyclerView, itemClick), RecyclerViewFastScroller.OnPopupTextUpdate {
+) : MyRecyclerViewListAdapter<Conversation>(activity, recyclerView, ConversationDiffCallback(), itemClick), RecyclerViewFastScroller.OnPopupTextUpdate {
     private var fontSize = activity.getTextSize()
     private var drafts = HashMap<Long, String?>()
 
+    private var recyclerViewState: Parcelable? = null
+
     init {
         setupDragListener(true)
         fetchDrafts(drafts)
+        setHasStableIds(true)
+
+        registerAdapterDataObserver(object : RecyclerView.AdapterDataObserver() {
+            override fun onChanged() = restoreRecyclerViewState()
+            override fun onItemRangeMoved(fromPosition: Int, toPosition: Int, itemCount: Int) = restoreRecyclerViewState()
+            override fun onItemRangeInserted(positionStart: Int, itemCount: Int) = restoreRecyclerViewState()
+        })
     }
 
     override fun getActionMenuId() = R.menu.cab_conversations
@@ -71,13 +83,13 @@ class ConversationsAdapter(
         }
     }
 
-    override fun getSelectableItemCount() = conversations.size
+    override fun getSelectableItemCount() = itemCount
 
     override fun getIsItemSelectable(position: Int) = true
 
-    override fun getItemSelectionKey(position: Int) = conversations.getOrNull(position)?.hashCode()
+    override fun getItemSelectionKey(position: Int) = currentList.getOrNull(position)?.hashCode()
 
-    override fun getItemKeyPosition(key: Int) = conversations.indexOfFirst { it.hashCode() == key }
+    override fun getItemKeyPosition(key: Int) = currentList.indexOfFirst { it.hashCode() == key }
 
     override fun onActionModeCreated() {}
 
@@ -86,14 +98,14 @@ class ConversationsAdapter(
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int) = createViewHolder(R.layout.item_conversation, parent)
 
     override fun onBindViewHolder(holder: ViewHolder, position: Int) {
-        val conversation = conversations[position]
+        val conversation = getItem(position)
-        holder.bindView(conversation, true, true) { itemView, layoutPosition ->
+        holder.bindView(conversation, allowSingleClick = true, allowLongClick = true) { itemView, _ ->
             setupView(itemView, conversation)
         }
         bindViewHolder(holder)
     }
 
-    override fun getItemCount() = conversations.size
+    override fun getItemId(position: Int) = getItem(position).threadId
 
     override fun onViewRecycled(holder: ViewHolder) {
         super.onViewRecycled(holder)
@@ -118,8 +130,7 @@ class ConversationsAdapter(
         }
 
         val numbersToBlock = getSelectedItems()
-        val positions = getSelectedItemPositions()
+        val newList = currentList.toMutableList().apply { removeAll(numbersToBlock) }
-        conversations.removeAll(numbersToBlock)
 
         ensureBackgroundThread {
             numbersToBlock.map { it.phoneNumber }.forEach { number ->
@@ -127,7 +138,7 @@ class ConversationsAdapter(
             }
 
             activity.runOnUiThread {
-                removeSelectedItems(positions)
+                submitList(newList)
                 finishActMode()
             }
         }
@@ -165,25 +176,25 @@ class ConversationsAdapter(
             return
         }
 
-        val conversationsToRemove = conversations.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
+        val conversationsToRemove = currentList.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
-        val positions = getSelectedItemPositions()
         conversationsToRemove.forEach {
             activity.deleteConversation(it.threadId)
             activity.notificationManager.cancel(it.hashCode())
         }
 
-        try {
+        val newList = try {
-            conversations.removeAll(conversationsToRemove.toSet())
+            currentList.toMutableList().apply { removeAll(conversationsToRemove) }
         } catch (ignored: Exception) {
+            currentList.toMutableList()
         }
 
         activity.runOnUiThread {
-            if (conversationsToRemove.isEmpty()) {
+            if (newList.none { selectedKeys.contains(it.hashCode()) }) {
                 refreshMessages()
                 finishActMode()
             } else {
-                removeSelectedItems(positions)
+                submitList(newList)
-                if (conversations.isEmpty()) {
+                if (newList.isEmpty()) {
                     refreshMessages()
                 }
             }
@@ -195,7 +206,7 @@ class ConversationsAdapter(
             return
         }
 
-        val conversationsMarkedAsRead = conversations.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
+        val conversationsMarkedAsRead = currentList.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
         ensureBackgroundThread {
             conversationsMarkedAsRead.filter { conversation -> !conversation.read }.forEach {
                 activity.markThreadMessagesRead(it.threadId)
@@ -213,7 +224,7 @@ class ConversationsAdapter(
             return
         }
 
-        val conversationsMarkedAsUnread = conversations.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
+        val conversationsMarkedAsUnread = currentList.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
         ensureBackgroundThread {
             conversationsMarkedAsUnread.filter { conversation -> conversation.read }.forEach {
                 activity.markThreadMessagesUnread(it.threadId)
@@ -236,7 +247,7 @@ class ConversationsAdapter(
         }
     }
 
-    private fun getSelectedItems() = conversations.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
+    private fun getSelectedItems() = currentList.filter { selectedKeys.contains(it.hashCode()) } as ArrayList<Conversation>
 
     private fun pinConversation(pin: Boolean) {
         val conversations = getSelectedItems()
@@ -275,14 +286,9 @@ class ConversationsAdapter(
         notifyDataSetChanged()
     }
 
-    fun updateConversations(newConversations: ArrayList<Conversation>) {
+    fun updateConversations(newConversations: ArrayList<Conversation>, commitCallback: (() -> Unit)? = null) {
-        val latestConversations = newConversations.clone() as ArrayList<Conversation>
+        saveRecyclerViewState()
-        val oldHashCode = conversations.hashCode()
+        submitList(newConversations.toList(), commitCallback)
-        val newHashCode = latestConversations.hashCode()
-        if (newHashCode != oldHashCode) {
-            conversations = latestConversations
-            notifyDataSetChanged()
-        }
     }
 
     fun updateDrafts() {
@@ -346,5 +352,23 @@ class ConversationsAdapter(
         }
     }
 
-    override fun onChange(position: Int) = conversations.getOrNull(position)?.title ?: ""
+    override fun onChange(position: Int) = currentList.getOrNull(position)?.title ?: ""
+
+    private fun saveRecyclerViewState() {
+        recyclerViewState = recyclerView.layoutManager?.onSaveInstanceState()
+    }
+
+    private fun restoreRecyclerViewState() {
+        recyclerView.layoutManager?.onRestoreInstanceState(recyclerViewState)
+    }
+
+    private class ConversationDiffCallback : DiffUtil.ItemCallback<Conversation>() {
+        override fun areItemsTheSame(oldItem: Conversation, newItem: Conversation): Boolean {
+            return oldItem.areItemsTheSame(newItem)
+        }
+
+        override fun areContentsTheSame(oldItem: Conversation, newItem: Conversation): Boolean {
+            return oldItem.areContentsTheSame(newItem)
+        }
+    }
 }

app/src/main/kotlin/com/simplemobiletools/smsmessenger/models/Conversation.kt

@@ -18,6 +18,10 @@ data class Conversation(
     @ColumnInfo(name = "is_scheduled") var isScheduled: Boolean = false
 ) {
 
+    fun areItemsTheSame(other: Conversation): Boolean {
+        return threadId == other.threadId
+    }
+
     fun areContentsTheSame(other: Conversation): Boolean {
         return snippet == other.snippet &&
             date == other.date &&