Created a method that is always listening to changes in the database and finds out when at least one UserAccount involved in a transaction is not present in the user_accounts db table. When such accounts are found they are retrieved in a form of a list and their information is requested to the BitShares nodes through graphenej's NetworkService and saved into the db once a response is received. The updated user account information is automatically displayed in the transactions list because of AAC's ViewModel, LiveData and Room.

app/src/main/java/cy/agorise/bitsybitshareswallet/activities/ConnectedActivity.kt

@@ -10,9 +10,16 @@ import android.os.IBinder
 import android.util.Log
 import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
+import androidx.lifecycle.Observer
+import androidx.lifecycle.ViewModelProviders
+import cy.agorise.bitsybitshareswallet.utils.Constants
+import cy.agorise.bitsybitshareswallet.viewmodels.UserAccountViewModel
+import cy.agorise.graphenej.UserAccount
 import cy.agorise.graphenej.api.ConnectionStatusUpdate
 import cy.agorise.graphenej.api.android.NetworkService
 import cy.agorise.graphenej.api.android.RxBus
+import cy.agorise.graphenej.api.calls.GetAccounts
+import cy.agorise.graphenej.models.AccountProperties
 import cy.agorise.graphenej.models.FullAccountDetails
 import cy.agorise.graphenej.models.HistoryOperationDetail
 import cy.agorise.graphenej.models.JsonRpcResponse
@@ -23,8 +30,9 @@ import io.reactivex.disposables.Disposable
  * Class in charge of managing the connection to graphenej's NetworkService
  */
 abstract class ConnectedActivity : AppCompatActivity(), ServiceConnection {
+    private val TAG = this.javaClass.simpleName
 
-    private val TAG = "ConnectedActivity"
+    private lateinit var mUserAccountViewModel: UserAccountViewModel
 
     private val mHandler = Handler()
 
@@ -33,6 +41,8 @@ abstract class ConnectedActivity : AppCompatActivity(), ServiceConnection {
 
     private var storedOpCount: Long = -1
 
+    private var missingUserAccounts = ArrayList<UserAccount>()
+
     /* Network service connection */
     protected var mNetworkService: NetworkService? = null
 
@@ -52,7 +62,10 @@ abstract class ConnectedActivity : AppCompatActivity(), ServiceConnection {
                     handleJsonRpcResponse(message)
                     // Payment detection focused responses
                     if (message.error == null) {
-//                        if (message.result is List<*> && (message.result as List<*>).size > 0) {
+                        if (message.result is List<*> && (message.result as List<*>).size > 0) {
+                            if ((message.result as List<*>)[0] is AccountProperties) {
+                                handleAccountProperties(message.result as List<AccountProperties>)
+                            }
 //                            if ((message.result as List<*>)[0] is FullAccountDetails) {
 //                                if (message.id == recurrentAccountUpdateId) {
 //                                    handleAccountDetails((message.result as List<*>)[0] as FullAccountDetails)
@@ -62,7 +75,7 @@ abstract class ConnectedActivity : AppCompatActivity(), ServiceConnection {
 //                            }
 //                        } else if (message.result is HistoryOperationDetail && message.id == accountOpRequestId) {
 //                            handleNewOperations(message.result as HistoryOperationDetail)
-//                        }
+                        }
                     } else {
                         // In case of error
                         Log.e(TAG, "Got error message from full node. Msg: " + message.error.message)
@@ -81,36 +94,47 @@ abstract class ConnectedActivity : AppCompatActivity(), ServiceConnection {
                     }
                 }
             }
+
+        // Configure UserAccountViewModel to show the current account
+        mUserAccountViewModel = ViewModelProviders.of(this).get(UserAccountViewModel::class.java)
+
+        mUserAccountViewModel.getMissingUserAccountIds().observe(this, Observer<List<String>>{ userAccountIds ->
+            if (!userAccountIds.isEmpty()) {
+                for (userAccountId in userAccountIds)
+                    missingUserAccounts.add(UserAccount(userAccountId))
+
+                mHandler.postDelayed(mRequestMissingUserAccountsTask, Constants.NETWORK_SERVICE_RETRY_PERIOD)
+            }
+        })
     }
 
-    override fun onDestroy() {
+    private fun handleAccountProperties(accountPropertiesList: List<AccountProperties>) {
-        super.onDestroy()
+        val userAccounts = ArrayList<cy.agorise.bitsybitshareswallet.database.entities.UserAccount>()
-        if (!mDisposable!!.isDisposed) mDisposable!!.dispose()
+
+        for (accountProperties in accountPropertiesList) {
+            val userAccount = cy.agorise.bitsybitshareswallet.database.entities.UserAccount(
+                accountProperties.id,
+                accountProperties.name,
+                accountProperties.membership_expiration_date == Constants.LIFETIME_EXPIRATION_DATE
+            )
+
+            userAccounts.add(userAccount)
         }
 
-    override fun onResume() {
+        mUserAccountViewModel.insertAll(userAccounts)
-        super.onResume()
+    }
 
-        val intent = Intent(this, NetworkService::class.java)
+    /**
-        if (bindService(intent, this, Context.BIND_AUTO_CREATE)) {
+     * Task used to obtain the missing UserAccounts.
-            mShouldUnbindNetwork = true
+     */
+    private val mRequestMissingUserAccountsTask = object : Runnable {
+        override fun run() {
+            if (mNetworkService!!.isConnected) {
+                mNetworkService!!.sendMessage(GetAccounts(missingUserAccounts), GetAccounts.REQUIRED_API)
             } else {
-            Log.e(TAG, "Binding to the network service failed.")
+                mHandler.postDelayed(this, Constants.NETWORK_SERVICE_RETRY_PERIOD)
             }
-//        mHandler.postDelayed(mCheckMissingPaymentsTask, Constants.MISSING_PAYMENT_CHECK_PERIOD)
-
-//        storedOpCount = PreferenceManager.getDefaultSharedPreferences(this)
-//            .getLong(Constants.KEY_ACCOUNT_OPERATION_COUNT, -1)
         }
-
-    override fun onPause() {
-        super.onPause()
-        // Unbinding from network service
-        if (mShouldUnbindNetwork) {
-            unbindService(this)
-            mShouldUnbindNetwork = false
-        }
-//        mHandler.removeCallbacks(mCheckMissingPaymentsTask)
     }
 
     /**
@@ -146,7 +170,37 @@ abstract class ConnectedActivity : AppCompatActivity(), ServiceConnection {
         mNetworkService = binder.service
     }
 
-    override fun onServiceDisconnected(name: ComponentName?) {
+    override fun onServiceDisconnected(name: ComponentName?) { }
+
+    override fun onPause() {
+        super.onPause()
+        // Unbinding from network service
+        if (mShouldUnbindNetwork) {
+            unbindService(this)
+            mShouldUnbindNetwork = false
+        }
+//        mHandler.removeCallbacks(mCheckMissingPaymentsTask)
+        mHandler.removeCallbacks(mRequestMissingUserAccountsTask)
+    }
+
+    override fun onResume() {
+        super.onResume()
+
+        val intent = Intent(this, NetworkService::class.java)
+        if (bindService(intent, this, Context.BIND_AUTO_CREATE)) {
+            mShouldUnbindNetwork = true
+        } else {
+            Log.e(TAG, "Binding to the network service failed.")
+        }
+//        mHandler.postDelayed(mCheckMissingPaymentsTask, Constants.MISSING_PAYMENT_CHECK_PERIOD)
+
+//        storedOpCount = PreferenceManager.getDefaultSharedPreferences(this)
+//            .getLong(Constants.KEY_ACCOUNT_OPERATION_COUNT, -1)
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        if (!mDisposable!!.isDisposed) mDisposable!!.dispose()
     }
 
     /**

app/src/main/java/cy/agorise/bitsybitshareswallet/adapters/TransfersDetailsAdapter.kt

@@ -88,8 +88,8 @@ class TransfersDetailsAdapter(private val context: Context) :
             if(transferDetail.direction) R.color.colorReceive else R.color.colorSend
         ))
 
-        viewHolder.tvFrom.text = transferDetail.from
+        viewHolder.tvFrom.text = transferDetail.from ?: ""
-        viewHolder.tvTo.text = transferDetail.to
+        viewHolder.tvTo.text = transferDetail.to ?: ""
 
         viewHolder.tvDate.text = "02 Oct"
         viewHolder.tvTime.text = "15:01:18 CET"

app/src/main/java/cy/agorise/bitsybitshareswallet/database/daos/UserAccountDao.kt

@@ -3,6 +3,7 @@ package cy.agorise.bitsybitshareswallet.database.daos
 import androidx.lifecycle.LiveData
 import androidx.room.Dao
 import androidx.room.Insert
+import androidx.room.OnConflictStrategy
 import androidx.room.Query
 import cy.agorise.bitsybitshareswallet.database.entities.UserAccount
 
@@ -11,9 +12,16 @@ interface UserAccountDao {
     @Insert
     fun insert(userAccount: UserAccount)
 
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertAll(userAccounts: List<UserAccount>)
+
     @Query("SELECT * FROM user_accounts WHERE user_accounts.id = :id")
     fun getUserAccount(id: String): LiveData<UserAccount>
 
     @Query("SELECT * FROM user_accounts")
-    fun getAllUserAccounts(): LiveData<List<UserAccount>>
+    fun getAll(): LiveData<List<UserAccount>>
+
+    // TODO not sure if this is the best place for this query as it involves two entities
+    @Query("SELECT DISTINCT destination FROM transfers WHERE destination NOT IN (SELECT id FROM user_accounts) UNION SELECT DISTINCT source FROM transfers WHERE source NOT IN (SELECT id FROM user_accounts)")
+    fun getMissingAccountIds(): LiveData<List<String>>
 }

app/src/main/java/cy/agorise/bitsybitshareswallet/database/joins/TransferDetail.kt

@@ -2,8 +2,8 @@ package cy.agorise.bitsybitshareswallet.database.joins
 
 data class TransferDetail(
     val id: String,
-    val from: String,
+    val from: String?,
-    val to: String,
+    val to: String?,
     val direction: Boolean, // True -> Received, False -> Sent
 //    val date: Long,
     val cryptoAmount: Long,

app/src/main/java/cy/agorise/bitsybitshareswallet/database/joins/TransferDetailDao.kt

@@ -7,6 +7,6 @@ import androidx.room.Query
 @Dao
 interface TransferDetailDao {
 
-    @Query("SELECT transfers.id, IFNULL((SELECT name FROM user_accounts WHERE user_accounts.id=transfers.source), '') AS `from`, IFNULL((SELECT name FROM user_accounts WHERE user_accounts.id=transfers.destination), '') AS `to`, (CASE WHEN destination=:userId THEN 1 ELSE 0 END) AS `direction`, transfers.transfer_amount AS `cryptoAmount`, assets.precision AS `cryptoPrecision`, assets.symbol AS cryptoSymbol FROM transfers INNER JOIN assets WHERE transfers.transfer_asset_id = assets.id")
+    @Query("SELECT transfers.id, (SELECT name FROM user_accounts WHERE user_accounts.id=transfers.source) AS `from`, (SELECT name FROM user_accounts WHERE user_accounts.id=transfers.destination) AS `to`, (CASE WHEN destination=:userId THEN 1 ELSE 0 END) AS `direction`, transfers.transfer_amount AS `cryptoAmount`, assets.precision AS `cryptoPrecision`, assets.symbol AS cryptoSymbol FROM transfers INNER JOIN assets WHERE transfers.transfer_asset_id = assets.id")
     fun getAll(userId: String): LiveData<List<TransferDetail>>
 }

app/src/main/java/cy/agorise/bitsybitshareswallet/processors/MissingAccountsLoader.kt

@@ -1,42 +0,0 @@
-//package cy.agorise.bitsybitshareswallet.processors
-//
-//import android.content.Context
-//import androidx.lifecycle.Lifecycle
-//import cy.agorise.graphenej.api.android.RxBus
-//import cy.agorise.graphenej.api.calls.GetAccounts
-//import cy.agorise.graphenej.entities.AccountProperties
-//import cy.agorise.graphenej.entities.JsonRpcResponse
-//import io.reactivex.android.schedulers.AndroidSchedulers
-//
-///**
-// * Loader used to fetch the missing accounts and update the database
-// */
-//class MissingAccountsLoader(context: Context, lifecycle: Lifecycle) : BaseDataLoader(context, lifecycle) {
-//
-//    init {
-//        mDisposable = RxBus.getBusInstance()
-//            .asFlowable()
-//            .observeOn(AndroidSchedulers.mainThread())
-//            .subscribe { message ->
-//                if (message is JsonRpcResponse<*>) {
-//                    if (message.result is List<*> &&
-//                        (message.result as List<*>).size > 0 &&
-//                        (message.result as List<*>)[0] is AccountProperties
-//                    ) {
-//                        database.putUserAccounts(message.result as List<AccountProperties>)
-//                    }
-//                }
-//            }
-//    }
-//
-//    protected fun onNetworkReady() {
-//        requestAccountInfo()
-//    }
-//
-//    fun requestAccountInfo() {
-//        val missingAccountNames = database.getMissingAccountNames()
-//        if (missingAccountNames.size > 0) {
-//            mNetworkService.sendMessage(GetAccounts(missingAccountNames), GetAccounts.REQUIRED_API)
-//        }
-//    }
-//}

app/src/main/java/cy/agorise/bitsybitshareswallet/processors/TransfersLoader.kt

@@ -187,18 +187,21 @@ class TransfersLoader(private var mContext: Context?, private val mLifeCycle: Li
             // If we are in debug mode, we first erase all entries in the 'transfer' table
             transferRepository!!.deleteAll()
         }
-        mDisposables.add(transferRepository!!.getCount()
+        mDisposables.add(
+            transferRepository!!.getCount()
                 .subscribeOn(Schedulers.computation())
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe { transferCount ->
                      if (transferCount > 0) {
                         // If we already have some transfers in the database, we might want to skip the request
                         // straight to the last batch
-                    historicalTransferCount = Math.floor((transferCount / HISTORICAL_TRANSFER_BATCH_SIZE).toDouble()).toInt()
+                        historicalTransferCount = Math.floor((transferCount /
+                                HISTORICAL_TRANSFER_BATCH_SIZE).toDouble()).toInt()
                     }
                     // Retrieving account transactions
                     loadNextOperationsBatch()
-            })
+                }
+        )
     }
 
     /**
@@ -213,6 +216,7 @@ class TransfersLoader(private var mContext: Context?, private val mLifeCycle: Li
         historicalTransferCount++
 
         val insertedCount = transferRepository!!.insertAll(processOperationList(operationHistoryList))
+        // TODO return number of inserted rows
 //        Log.d(TAG, String.format("Inserted count: %d, list size: %d", insertedCount, operationHistoryList.size))
         if (/* insertedCount == 0 && */ operationHistoryList.isEmpty()) {
             // TODO Terminate process and obtain MissingTimes and MissingEquivalentValues

app/src/main/java/cy/agorise/bitsybitshareswallet/repositories/UserAccountRepository.kt

@@ -1,18 +1,18 @@
 package cy.agorise.bitsybitshareswallet.repositories
 
-import android.app.Application
+import android.content.Context
 import android.os.AsyncTask
 import androidx.lifecycle.LiveData
 import cy.agorise.bitsybitshareswallet.database.BitsyDatabase
 import cy.agorise.bitsybitshareswallet.database.daos.UserAccountDao
 import cy.agorise.bitsybitshareswallet.database.entities.UserAccount
 
-class UserAccountRepository internal constructor(application: Application) {
+class UserAccountRepository internal constructor(context: Context) {
 
     private val mUserAccountDao: UserAccountDao
 
     init {
-        val db = BitsyDatabase.getDatabase(application)
+        val db = BitsyDatabase.getDatabase(context)
         mUserAccountDao = db!!.userAccountDao()
     }
 
@@ -20,10 +20,18 @@ class UserAccountRepository internal constructor(application: Application) {
         insertAsyncTask(mUserAccountDao).execute(userAccount)
     }
 
+    fun insertAll(userAccounts: List<UserAccount>) {
+        insertAllAsyncTask(mUserAccountDao).execute(userAccounts)
+    }
+
     fun getUserAccount(id: String): LiveData<UserAccount> {
         return mUserAccountDao.getUserAccount(id)
     }
 
+    fun getMissingUserAccountIds(): LiveData<List<String>> {
+        return mUserAccountDao.getMissingAccountIds()
+    }
+
     private class insertAsyncTask internal constructor(private val mAsyncTaskDao: UserAccountDao) :
         AsyncTask<UserAccount, Void, Void>() {
 
@@ -32,4 +40,13 @@ class UserAccountRepository internal constructor(application: Application) {
             return null
         }
     }
+
+    private class insertAllAsyncTask internal constructor(private val mAsyncTaskDao: UserAccountDao) :
+        AsyncTask<List<UserAccount>, Void, Void>() {
+
+        override fun doInBackground(vararg userAccounts: List<UserAccount>): Void? {
+            mAsyncTaskDao.insertAll(userAccounts[0])
+            return null
+        }
+    }
 }

app/src/main/java/cy/agorise/bitsybitshareswallet/utils/Constants.kt

@@ -39,10 +39,15 @@ object Constants {
     const val LIFETIME_EXPIRATION_DATE = "1969-12-31T23:59:59"
 
     /**
-     * Smartcoin options for output
+     * Time period between two consecutive requests to the full node performed whenever we have
+     * open payment requests as a matter of redundancy.
      */
-    val BTS     = Asset("1.3.0")
+    const val MISSING_PAYMENT_CHECK_PERIOD: Long = 5000
-    val bitUSD  = Asset("1.3.121")
+
+    /**
+     * Time period to wait to send a request to the NetworkService, and retry in case it is still not connected
+     */
+    const val NETWORK_SERVICE_RETRY_PERIOD: Long = 5000
 
     /** Key used to store the night mode setting into the shared preferences */
     const val KEY_NIGHT_MODE_ACTIVATED = "key_night_mode_activated"

app/src/main/java/cy/agorise/bitsybitshareswallet/viewmodels/UserAccountViewModel.kt

@@ -13,7 +13,15 @@ class UserAccountViewModel(application: Application) : AndroidViewModel(applicat
         return mRepository.getUserAccount(id)
     }
 
+    internal fun getMissingUserAccountIds(): LiveData<List<String>> {
+        return mRepository.getMissingUserAccountIds()
+    }
+
 //    fun insert(userAccount: UserAccount) {
 //        mRepository.insert(userAccount)
 //    }
+
+    fun insertAll(userAccounts: List<UserAccount>) {
+        mRepository.insertAll(userAccounts)
+    }
 }