creating a room DB for storing conversations

app/build.gradle

@@ -1,6 +1,7 @@
 apply plugin: 'com.android.application'
 apply plugin: 'kotlin-android'
 apply plugin: 'kotlin-android-extensions'
+apply plugin: 'kotlin-kapt'
 
 def keystorePropertiesFile = rootProject.file("keystore.properties")
 def keystoreProperties = new Properties()
@@ -56,8 +57,12 @@ android {
 }
 
 dependencies {
-    implementation 'com.simplemobiletools:commons:5.28.19'
+    implementation 'com.simplemobiletools:commons:5.28.24'
     implementation 'org.greenrobot:eventbus:3.2.0'
     implementation 'com.klinkerapps:android-smsmms:5.2.6'
     implementation 'com.github.tibbi:IndicatorFastScroll:08f512858a'
+
+    kapt "androidx.room:room-compiler:2.2.5"
+    implementation "androidx.room:room-runtime:2.2.5"
+    annotationProcessor "androidx.room:room-compiler:2.2.5"
 }

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

@@ -168,7 +168,7 @@ class MainActivity : SimpleActivity() {
 
                 ConversationsAdapter(this, conversations, conversations_list, conversations_fastscroller) {
                     Intent(this, ThreadActivity::class.java).apply {
-                        putExtra(THREAD_ID, (it as Conversation).id)
+                        putExtra(THREAD_ID, (it as Conversation).system_id)
                         putExtra(THREAD_TITLE, it.title)
                         startActivity(this)
                     }

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

@@ -59,9 +59,9 @@ class ConversationsAdapter(activity: SimpleActivity, var conversations: ArrayLis
 
     override fun getIsItemSelectable(position: Int) = true
 
-    override fun getItemSelectionKey(position: Int) = conversations.getOrNull(position)?.id
+    override fun getItemSelectionKey(position: Int) = conversations.getOrNull(position)?.system_id
 
-    override fun getItemKeyPosition(key: Int) = conversations.indexOfFirst { it.id == key }
+    override fun getItemKeyPosition(key: Int) = conversations.indexOfFirst { it.system_id == key }
 
     override fun onActionModeCreated() {}
 
@@ -129,10 +129,10 @@ class ConversationsAdapter(activity: SimpleActivity, var conversations: ArrayLis
             return
         }
 
-        val conversationsToRemove = conversations.filter { selectedKeys.contains(it.id) } as ArrayList<Conversation>
+        val conversationsToRemove = conversations.filter { selectedKeys.contains(it.system_id) } as ArrayList<Conversation>
         val positions = getSelectedItemPositions()
         conversationsToRemove.forEach {
-            activity.deleteConversation(it.id)
+            activity.deleteConversation(it.system_id)
         }
         conversations.removeAll(conversationsToRemove)
 
@@ -164,7 +164,7 @@ class ConversationsAdapter(activity: SimpleActivity, var conversations: ArrayLis
         }
     }
 
-    private fun getSelectedItems() = conversations.filter { selectedKeys.contains(it.id) } as ArrayList<Conversation>
+    private fun getSelectedItems() = conversations.filter { selectedKeys.contains(it.system_id) } as ArrayList<Conversation>
 
     override fun onViewRecycled(holder: ViewHolder) {
         super.onViewRecycled(holder)
@@ -175,7 +175,7 @@ class ConversationsAdapter(activity: SimpleActivity, var conversations: ArrayLis
 
     private fun setupView(view: View, conversation: Conversation) {
         view.apply {
-            conversation_frame.isSelected = selectedKeys.contains(conversation.id)
+            conversation_frame.isSelected = selectedKeys.contains(conversation.system_id)
 
             conversation_address.text = conversation.title
             conversation_body_short.text = conversation.snippet

app/src/main/kotlin/com/simplemobiletools/smsmessenger/databases/MessagesDatabase.kt

@@ -0,0 +1,30 @@
+package com.simplemobiletools.smsmessenger.databases
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import com.simplemobiletools.smsmessenger.interfaces.ConversationsDao
+import com.simplemobiletools.smsmessenger.models.Conversation
+
+@Database(entities = [(Conversation::class)], version = 1)
+abstract class MessagesDatabase : RoomDatabase() {
+
+    abstract fun ConversationsDao(): ConversationsDao
+
+    companion object {
+        private var db: MessagesDatabase? = null
+
+        fun getInstance(context: Context): MessagesDatabase {
+            if (db == null) {
+                synchronized(MessagesDatabase::class) {
+                    if (db == null) {
+                        db = Room.databaseBuilder(context.applicationContext, MessagesDatabase::class.java, "conversations.db")
+                            .build()
+                    }
+                }
+            }
+            return db!!
+        }
+    }
+}

app/src/main/kotlin/com/simplemobiletools/smsmessenger/extensions/Context.kt

@@ -22,7 +22,9 @@ import com.simplemobiletools.commons.helpers.*
 import com.simplemobiletools.commons.models.SimpleContact
 import com.simplemobiletools.smsmessenger.R
 import com.simplemobiletools.smsmessenger.activities.ThreadActivity
+import com.simplemobiletools.smsmessenger.databases.MessagesDatabase
 import com.simplemobiletools.smsmessenger.helpers.*
+import com.simplemobiletools.smsmessenger.interfaces.ConversationsDao
 import com.simplemobiletools.smsmessenger.models.*
 import com.simplemobiletools.smsmessenger.receivers.MarkAsReadReceiver
 import java.util.*
@@ -30,6 +32,10 @@ import kotlin.collections.ArrayList
 
 val Context.config: Config get() = Config.newInstance(applicationContext)
 
+fun Context.getMessagessDB() = MessagesDatabase.getInstance(this)
+
+val Context.conversationsDB: ConversationsDao get() = getMessagessDB().ConversationsDao()
+
 fun Context.getMessages(threadId: Int): ArrayList<Message> {
     val uri = Sms.CONTENT_URI
     val projection = arrayOf(
@@ -215,7 +221,7 @@ fun Context.getConversations(): ArrayList<Conversation> {
         val photoUri = if (phoneNumbers.size == 1) simpleContactHelper.getPhotoUriFromPhoneNumber(phoneNumbers.first()) else ""
         val isGroupConversation = phoneNumbers.size > 1
         val read = cursor.getIntValue(Threads.READ) == 1
-        val conversation = Conversation(id, snippet, date.toInt(), read, title, photoUri, isGroupConversation, phoneNumbers.first())
+        val conversation = Conversation(0, id, snippet, date.toInt(), read, title, photoUri, isGroupConversation, phoneNumbers.first())
 
         conversations.add(conversation)
     }

app/src/main/kotlin/com/simplemobiletools/smsmessenger/interfaces/ConversationsDao.kt

@@ -0,0 +1,6 @@
+package com.simplemobiletools.smsmessenger.interfaces
+
+import androidx.room.Dao
+
+@Dao
+interface ConversationsDao

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

@@ -1,5 +1,19 @@
 package com.simplemobiletools.smsmessenger.models
 
+import androidx.room.ColumnInfo
+import androidx.room.Entity
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "conversations", indices = [(Index(value = ["id"], unique = true))])
 data class Conversation(
-    val id: Int, val snippet: String, val date: Int, val read: Boolean, var title: String, var photoUri: String,
+    @PrimaryKey(autoGenerate = true) var id: Long?,
-    val isGroupConversation: Boolean, val phoneNumber: String)
+    @ColumnInfo(name = "system_id") var system_id: Int,
+    @ColumnInfo(name = "snippet") var snippet: String,
+    @ColumnInfo(name = "date") var date: Int,
+    @ColumnInfo(name = "read") var read: Boolean,
+    @ColumnInfo(name = "title") var title: String,
+    @ColumnInfo(name = "photo_uri") var photoUri: String,
+    @ColumnInfo(name = "is_group_conversation") var isGroupConversation: Boolean,
+    @ColumnInfo(name = "phone_number") var phoneNumber: String
+)