Make ReceiveTransactionFragment extend from ConnectedFragment to reduce boilerplate and repeated code. Change the method used to obtain the Assets list from the db in ReceiveTransactionFragment, it now retrieved only those Assets for which the user has a Balance > 0. Improve ReceiveTransactionFragment's function that obtains the suggestions for the AutoCompleteTextView when the user wants to receive a different Asset, to avoid crashes if the information received does not have the expected format.

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

@@ -15,6 +15,6 @@ interface AssetDao {
     @Insert(onConflict = OnConflictStrategy.REPLACE)
     fun insertAll(assets: List<Asset>)
 
-    @Query("SELECT * FROM assets")
+    @Query("SELECT id, symbol, precision, description, bit_asset_id FROM assets INNER JOIN balances WHERE assets.id = balances.asset_id AND balances.asset_amount > 0")
-    fun getAll(): LiveData<List<Asset>>
+    fun getAllNonZero(): LiveData<List<Asset>>
 }

app/src/main/java/cy/agorise/bitsybitshareswallet/fragments/ReceiveTransactionFragment.kt

@@ -1,15 +1,11 @@
 package cy.agorise.bitsybitshareswallet.fragments
 
 import android.Manifest
-import android.content.ComponentName
-import android.content.Context
 import android.content.Intent
-import android.content.ServiceConnection
 import android.content.pm.PackageManager
 import android.graphics.Bitmap
 import android.graphics.Color
 import android.os.Bundle
-import android.os.IBinder
 import android.preference.PreferenceManager
 import android.util.Log
 import android.view.*
@@ -17,7 +13,6 @@ import android.widget.AdapterView
 import android.widget.Toast
 import androidx.appcompat.widget.Toolbar
 import androidx.core.content.ContextCompat
-import androidx.fragment.app.Fragment
 import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProviders
 import com.google.common.primitives.UnsignedLong
@@ -36,12 +31,9 @@ import cy.agorise.bitsybitshareswallet.viewmodels.AssetViewModel
 import cy.agorise.bitsybitshareswallet.viewmodels.UserAccountViewModel
 import cy.agorise.graphenej.*
 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.ListAssets
 import cy.agorise.graphenej.models.JsonRpcResponse
 import io.reactivex.android.schedulers.AndroidSchedulers
-import io.reactivex.disposables.CompositeDisposable
 import kotlinx.android.synthetic.main.fragment_receive_transaction.*
 import java.lang.Exception
 import java.math.RoundingMode
@@ -51,16 +43,19 @@ import java.util.*
 import java.util.concurrent.TimeUnit
 import kotlin.collections.ArrayList
 
-class ReceiveTransactionFragment : Fragment(), ServiceConnection {
+class ReceiveTransactionFragment : ConnectedFragment() {
-    private val TAG = this.javaClass.simpleName
 
-    private val RESPONSE_LIST_ASSETS = 1
+    companion object {
-    private val REQUEST_WRITE_EXTERNAL_STORAGE_PERMISSION = 100
+        private const val TAG = "ReceiveTransactionFrag"
+
+        private const val RESPONSE_LIST_ASSETS = 1
+        private const val REQUEST_WRITE_EXTERNAL_STORAGE_PERMISSION = 100
 
         /** Number of assets to request from the NetworkService to show as suggestions in the AutoCompleteTextView */
-    private val AUTO_SUGGEST_ASSET_LIMIT = 5
+        private const val AUTO_SUGGEST_ASSET_LIMIT = 5
 
-    private val OTHER_ASSET = "other_asset"
+        private const val OTHER_ASSET = "other_asset"
+    }
 
     private lateinit var mUserAccountViewModel: UserAccountViewModel
     private lateinit var mAssetViewModel: AssetViewModel
@@ -68,8 +63,6 @@ class ReceiveTransactionFragment : Fragment(), ServiceConnection {
     /** Current user account */
     private var mUserAccount: UserAccount? = null
 
-    private var mDisposables = CompositeDisposable()
-
     private var mAsset: Asset? = null
 
     private var mAssetsAdapter: AssetsAdapter? = null
@@ -86,12 +79,6 @@ class ReceiveTransactionFragment : Fragment(), ServiceConnection {
     // Map used to keep track of request and response id pairs
     private val responseMap = HashMap<Long, Int>()
 
-    /* Network service connection */
-    private var mNetworkService: NetworkService? = null
-
-    /** Flag used to keep track of the NetworkService binding state */
-    private var mShouldUnbindNetwork: Boolean = false
-
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
         setHasOptionsMenu(true)
 
@@ -127,7 +114,7 @@ class ReceiveTransactionFragment : Fragment(), ServiceConnection {
         // Configure Assets spinner to show Assets already saved into the db
         mAssetViewModel = ViewModelProviders.of(this).get(AssetViewModel::class.java)
 
-        mAssetViewModel.getAll().observe(this,
+        mAssetViewModel.getAllNonZero().observe(this,
             Observer<List<cy.agorise.bitsybitshareswallet.database.entities.Asset>> { assets ->
                 mAssets.clear()
                 mAssets.addAll(assets)
@@ -211,35 +198,33 @@ class ReceiveTransactionFragment : Fragment(), ServiceConnection {
             selectedInAutoCompleteTextView = true
             updateQR()
         }
-
-        // Connect to the RxBus, which receives events from the NetworkService
-        mDisposables.add(
-            RxBus.getBusInstance()
-                .asFlowable()
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe { handleIncomingMessage(it) }
-        )
     }
 
-    private fun handleIncomingMessage(message: Any?) {
+    override fun handleJsonRpcResponse(response: JsonRpcResponse<*>) {
-        if (message is JsonRpcResponse<*>) {
+        if (responseMap.containsKey(response.id)) {
-            if (responseMap.containsKey(message.id)) {
+            val responseType = responseMap[response.id]
-                val responseType = responseMap[message.id]
             when (responseType) {
-                    RESPONSE_LIST_ASSETS            -> handleListAssets(message.result as List<Asset>)
+                RESPONSE_LIST_ASSETS    -> handleListAssets(response.result)
             }
-                responseMap.remove(message.id)
+            responseMap.remove(response.id)
         }
-        } else if (message is ConnectionStatusUpdate) {
+    }
-            if (message.updateCode == ConnectionStatusUpdate.DISCONNECTED) {
+
+    override fun handleConnectionStatusUpdate(connectionStatusUpdate: ConnectionStatusUpdate) {
+        if (connectionStatusUpdate.updateCode == ConnectionStatusUpdate.DISCONNECTED) {
             // If we got a disconnection notification, we should clear our response map, since
             // all its stored request ids will now be reset
             responseMap.clear()
         }
     }
-    }
 
-    private fun handleListAssets(assetList: List<Asset>) {
+    /**
+     * Handles the list of assets returned from the node that correspond to what the user has typed in the Asset
+     * AutoCompleteTextView and adds them to its adapter to show as suggestions.
+     */
+    private fun handleListAssets(result: Any?) {
+        if (result is List<*> && result.isNotEmpty() && result[0] is Asset) {
+            val assetList = result as List<Asset>
             Log.d(TAG, "handleListAssets")
             val assets = ArrayList<cy.agorise.bitsybitshareswallet.database.entities.Asset>()
             for (_asset in assetList) {
@@ -256,6 +241,7 @@ class ReceiveTransactionFragment : Fragment(), ServiceConnection {
             mAutoSuggestAssetAdapter.setData(assets)
             mAutoSuggestAssetAdapter.notifyDataSetChanged()
         }
+    }
 
     private fun updateQR() {
         if (mAsset == null) {
@@ -422,39 +408,4 @@ class ReceiveTransactionFragment : Fragment(), ServiceConnection {
         shareIntent.type = "*/*"
         startActivity(Intent.createChooser(shareIntent, getString(R.string.text__share_with)))
     }
-
-    override fun onResume() {
-        super.onResume()
-
-        val intent = Intent(context, NetworkService::class.java)
-        if (context?.bindService(intent, this, Context.BIND_AUTO_CREATE) == true) {
-            mShouldUnbindNetwork = true
-        } else {
-            Log.e(TAG, "Binding to the network service failed.")
-        }
-    }
-
-    override fun onPause() {
-        super.onPause()
-
-        // Unbinding from network service
-        if (mShouldUnbindNetwork) {
-            context?.unbindService(this)
-            mShouldUnbindNetwork = false
-        }
-    }
-
-    override fun onDestroy() {
-        super.onDestroy()
-
-        if (!mDisposables.isDisposed) mDisposables.dispose()
-    }
-
-    override fun onServiceDisconnected(name: ComponentName?) { }
-
-    override fun onServiceConnected(name: ComponentName?, service: IBinder?) {
-        // We've bound to LocalService, cast the IBinder and get LocalService instance
-        val binder = service as NetworkService.LocalBinder
-        mNetworkService = binder.service
-    }
 }

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

@@ -16,8 +16,8 @@ class AssetRepository internal constructor(context: Context) {
         mAssetDao = db!!.assetDao()
     }
 
-    fun getAll(): LiveData<List<Asset>> {
+    fun getAllNonZero(): LiveData<List<Asset>> {
-        return mAssetDao.getAll()
+        return mAssetDao.getAllNonZero()
     }
 
     fun insertAll(assets: List<Asset>) {

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

@@ -9,7 +9,7 @@ import cy.agorise.bitsybitshareswallet.repositories.AssetRepository
 class AssetViewModel(application: Application) : AndroidViewModel(application) {
     private var mRepository = AssetRepository(application)
 
-    internal fun getAll(): LiveData<List<Asset>> {
+    internal fun getAllNonZero(): LiveData<List<Asset>> {
-        return mRepository.getAll()
+        return mRepository.getAllNonZero()
     }
 }