Added a SearchView to MerchantsFragment's Toolbar, with an autocomplete feature that once the user starts writing shows suggestions to the user and listens when he selects one of those suggestions. The suggestions show dummy data for now, but it will query the database to obtain such suggestions.

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

@@ -2,22 +2,28 @@ package cy.agorise.bitsybitshareswallet.fragments
 
 import android.Manifest
 import android.annotation.SuppressLint
+import android.app.SearchManager
 import android.content.pm.PackageManager
+import android.database.Cursor
+import android.database.MatrixCursor
 import android.os.Bundle
 import android.util.Log
-import androidx.fragment.app.Fragment
 import com.google.android.gms.maps.GoogleMap
 import com.google.android.gms.maps.OnMapReadyCallback
 import com.google.android.gms.maps.SupportMapFragment
 
 import cy.agorise.bitsybitshareswallet.R
 import android.preference.PreferenceManager
+import android.provider.BaseColumns
 import android.view.*
 import android.widget.PopupWindow
 import android.widget.TextView
+import androidx.appcompat.widget.SearchView
 import androidx.appcompat.widget.SwitchCompat
 import androidx.appcompat.widget.Toolbar
 import androidx.core.content.ContextCompat
+import androidx.cursoradapter.widget.SimpleCursorAdapter
+import androidx.fragment.app.Fragment
 import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProviders
 import com.afollestad.materialdialogs.MaterialDialog
@@ -28,6 +34,7 @@ import com.google.maps.android.MarkerManager
 import com.google.maps.android.clustering.Cluster
 import com.google.maps.android.clustering.ClusterItem
 import com.google.maps.android.clustering.ClusterManager
+import com.jakewharton.rxbinding3.appcompat.queryTextChangeEvents
 import cy.agorise.bitsybitshareswallet.database.entities.Merchant
 import cy.agorise.bitsybitshareswallet.database.entities.Teller
 import cy.agorise.bitsybitshareswallet.utils.Constants
@@ -35,10 +42,13 @@ import cy.agorise.bitsybitshareswallet.utils.MerchantClusterRenderer
 import cy.agorise.bitsybitshareswallet.utils.TellerClusterRenderer
 import cy.agorise.bitsybitshareswallet.utils.toast
 import cy.agorise.bitsybitshareswallet.viewmodels.MerchantViewModel
+import io.reactivex.android.schedulers.AndroidSchedulers
+import io.reactivex.disposables.CompositeDisposable
 import java.lang.Exception
+import java.util.concurrent.TimeUnit
 
 
-class MerchantsFragment : Fragment(), OnMapReadyCallback {
+class MerchantsFragment : Fragment(), OnMapReadyCallback, SearchView.OnSuggestionListener {
 
     companion object {
         private const val TAG = "MerchantsFragment"
@@ -53,6 +63,11 @@ class MerchantsFragment : Fragment(), OnMapReadyCallback {
 
     private var mMarkerManager: MarkerManager? = null
 
+    /** Keeps track of all RxJava disposables, to make sure they are all disposed when the fragment is destroyed */
+    private var mDisposables = CompositeDisposable()
+
+    private var mSearchView: SearchView? = null
+
     // Cluster managers to create custom merchants and tellers clusters with a custom behavior too
     private var mMerchantClusterManager: ClusterManager<Merchant>? = null
     private var mTellerClusterManager: ClusterManager<Teller>? = null
@@ -128,6 +143,51 @@ class MerchantsFragment : Fragment(), OnMapReadyCallback {
 
     override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
         inflater.inflate(R.menu.menu_merchants, menu)
+
+        // Adds listener for the SearchView
+        val searchItem = menu.findItem(R.id.menu_search)
+        mSearchView = searchItem.actionView as SearchView
+        mSearchView?.suggestionsAdapter = SimpleCursorAdapter(context, android.R.layout.simple_list_item_1, null,
+            arrayOf(SearchManager.SUGGEST_COLUMN_TEXT_1), intArrayOf(android.R.id.text1))
+
+        // Add listener to changes in the SearchView's text to update the suggestions
+        mSearchView?.queryTextChangeEvents()
+            ?.skipInitialValue()
+            ?.debounce(500, TimeUnit.MILLISECONDS)
+            ?.map { it.queryText.toString().toLowerCase() }
+            ?.observeOn(AndroidSchedulers.mainThread())
+            ?.subscribe {
+                updateSearchViewSuggestions(it)
+            }?.let {
+                mDisposables.add(it)
+            }
+
+        mSearchView?.setOnSuggestionListener(this)
+    }
+
+    private fun updateSearchViewSuggestions(query: String) {
+        // TODO make call to the db to obtain the list of merchants/tellers
+        val cursor = MatrixCursor(arrayOf(BaseColumns._ID, SearchManager.SUGGEST_COLUMN_TEXT_1))
+
+        for (i in 1..3) {
+            cursor.addRow(arrayOf(i.toString(), "Merchant $i"))
+        }
+
+        mSearchView?.suggestionsAdapter?.changeCursor(cursor)
+    }
+
+    override fun onSuggestionSelect(position: Int): Boolean {
+        return onSuggestionClick(position)
+    }
+
+    override fun onSuggestionClick(position: Int): Boolean {
+        val cursor = mSearchView?.suggestionsAdapter?.getItem(position) as Cursor?
+        val name = cursor?.getString(cursor.getColumnIndex(SearchManager.SUGGEST_COLUMN_TEXT_1)) ?: ""
+        cursor?.close()
+
+        context?.toast(name)
+
+        return true
     }
 
     override fun onOptionsItemSelected(item: MenuItem?): Boolean {
@@ -418,4 +478,10 @@ class MerchantsFragment : Fragment(), OnMapReadyCallback {
 
         dismissPopupWindow()
     }
+
+    override fun onDestroy() {
+        super.onDestroy()
+
+        if (!mDisposables.isDisposed) mDisposables.dispose()
+    }
 }

app/src/main/res/menu/menu_merchants.xml

@@ -2,6 +2,13 @@
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
       xmlns:app="http://schemas.android.com/apk/res-auto">
 
+    <item
+        android:id="@+id/menu_search"
+        android:icon="@drawable/ic_search"
+        android:title="@string/title_search"
+        app:actionViewClass="androidx.appcompat.widget.SearchView"
+        app:showAsAction="always"/>
+
     <item
         android:id="@+id/menu_filter"
         android:icon="@drawable/ic_more_vert"