Created a three vertical dots icon and use it in the MerchantsFragment's Toolbar. Then forced that icon to display a custom Popup menu to control which pins will appear on the map (merchants and/or tellers).

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

@@ -2,20 +2,21 @@ package cy.agorise.bitsybitshareswallet.fragments
 
 import android.Manifest
 import android.annotation.SuppressLint
+import android.content.Context
 import android.content.pm.PackageManager
 import android.os.Bundle
 import android.util.Log
 import androidx.fragment.app.Fragment
-import android.view.LayoutInflater
-import android.view.View
-import android.view.ViewGroup
 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.view.*
+import android.widget.PopupWindow
 import android.widget.TextView
+import androidx.appcompat.widget.Toolbar
 import androidx.core.content.ContextCompat
 import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProviders
@@ -58,7 +59,16 @@ class MerchantsFragment : Fragment(), OnMapReadyCallback {
     private var selectedMerchant: Merchant? = null
     private var selectedTeller: Teller? = null
 
+    private var mPopupWindow: PopupWindow? = null
+    private var mToolbar: Toolbar? = null
+    private var screenWidth: Int = 0
+    private var popupWindowWidth: Int = 0
+
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+        setHasOptionsMenu(true)
+
+        mToolbar = activity?.findViewById(R.id.toolbar)
+
         return inflater.inflate(R.layout.fragment_merchants, container, false)
     }
 
@@ -70,6 +80,36 @@ class MerchantsFragment : Fragment(), OnMapReadyCallback {
         mapFragment.getMapAsync(this)
 
         mMerchantViewModel = ViewModelProviders.of(this).get(MerchantViewModel::class.java)
+
+        setupPopupWindow()
+
+        // Gets the screen width to correctly place the merchants and tellers popup menu
+        val display = activity?.windowManager?.defaultDisplay
+        screenWidth = display?.width ?: screenWidth
+    }
+
+    private fun setupPopupWindow() {
+        val popupView = layoutInflater?.inflate(R.layout.popup_menu_merchants, null)
+
+        // TODO get references to the popup menu items
+
+        mPopupWindow = PopupWindow(popupView, ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)
+        popupWindowWidth = mPopupWindow?.width ?: popupWindowWidth
+    }
+
+    override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
+        inflater.inflate(R.menu.menu_merchants, menu)
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem?): Boolean {
+        if (item?.itemId == R.id.menu_filter) {
+            if (mPopupWindow?.isShowing == false)
+                mPopupWindow?.showAsDropDown(mToolbar, screenWidth - popupWindowWidth, 0)
+            else
+                mPopupWindow?.dismiss()
+            return true
+        }
+        return super.onOptionsItemSelected(item)
     }
 
     /** Handles the result from the location permission request */

app/src/main/res/drawable/ic_more_vert.xml

@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#FFFFFF"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M12,8c1.1,0 2,-0.9 2,-2s-0.9,-2 -2,-2 -2,0.9 -2,2 0.9,2 2,2zM12,10c-1.1,0 -2,0.9 -2,2s0.9,2 2,2 2,-0.9 2,-2 -0.9,-2 -2,-2zM12,16c-1.1,0 -2,0.9 -2,2s0.9,2 2,2 2,-0.9 2,-2 -0.9,-2 -2,-2z"/>
+</vector>

app/src/main/res/drawable/popup_menu_merchants_background.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android" >
+    <corners android:radius="10dp" />
+    <solid android:color="?android:colorBackground" />
+</shape>

app/src/main/res/layout/fragment_settings.xml

@@ -2,6 +2,7 @@
 <LinearLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
@@ -30,17 +31,17 @@
                 android:textAppearance="@style/TextAppearance.Bitsy.Subtitle1"
                 android:textStyle="bold"/>
 
-            <Switch
+            <androidx.appcompat.widget.SwitchCompat
                 android:id="@+id/switchAutoClose"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:layout_marginTop="@dimen/spacing_different_topic"
-                android:switchPadding="12dp"
+                app:switchPadding="12dp"
                 android:text="@string/msg__close_timer"
                 android:textAppearance="@style/TextAppearance.Bitsy.Body1"
                 android:textColor="?android:textColorPrimary"/>
 
-            <Switch
+            <androidx.appcompat.widget.SwitchCompat
                 android:id="@+id/switchNightMode"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"

app/src/main/res/layout/popup_menu_merchants.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content" xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:orientation="vertical"
+    android:padding="8dp"
+    android:background="@drawable/popup_menu_merchants_background">
+
+    <androidx.appcompat.widget.SwitchCompat
+        android:id="@+id/switchMerchants"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        app:switchPadding="48dp"
+        android:text="@string/title_merchants"
+        android:textAppearance="@style/TextAppearance.Bitsy.Body1"
+        android:textColor="?android:textColorPrimary"/>
+
+    <androidx.appcompat.widget.SwitchCompat
+        android:id="@+id/switchTellers"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="8dp"
+        app:switchPadding="48dp"
+        android:text="@string/title_tellers"
+        android:textAppearance="@style/TextAppearance.Bitsy.Body1"
+        android:textColor="?android:textColorPrimary"/>
+
+    <TextView
+        android:id="@+id/tvInfo"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="10dp"
+        android:text="About"
+        android:clickable="true"
+        android:focusable="true"
+        android:textAppearance="@style/TextAppearance.Bitsy.Body1"/>
+
+</LinearLayout>

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

@@ -11,7 +11,7 @@
     <item
         android:id="@+id/merchants_dest"
         android:icon="@drawable/ic_merchants"
-        android:title="@string/title_merchants"
+        android:title="@string/title_merchants_and_tellers"
         app:showAsAction="always"/>
 
     <item

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

@@ -3,9 +3,9 @@
       xmlns:app="http://schemas.android.com/apk/res-auto">
 
     <item
-        android:id="@+id/menu_settings"
+        android:id="@+id/menu_filter"
-        android:icon="@drawable/ic_settings"
+        android:icon="@drawable/ic_more_vert"
-        android:title="@string/title_settings"
+        android:title="@string/title_filter"
-        app:showAsAction="never"/>
+        app:showAsAction="always"/>
 
 </menu>

app/src/main/res/navigation/mobile_navigation.xml

@@ -45,7 +45,7 @@
     <fragment
         android:id="@+id/merchants_dest"
         android:name="cy.agorise.bitsybitshareswallet.fragments.MerchantsFragment"
-        android:label="@string/title_merchants"
+        android:label="@string/title_merchants_and_tellers"
         tools:layout="@layout/fragment_merchants"/>
 
     <fragment

app/src/main/res/values-es/strings.xml

@@ -36,7 +36,7 @@
 
     <!-- Home -->
     <string name="title_transactions">Transacciones</string>
-    <string name="title_merchants">Comerciantes</string>
+    <string name="title_merchants_and_tellers">Comerciantes</string>
     <string name="title_receive">Recibir</string>
     <string name="title_balances">Balances</string>
     <string name="title_send">Enviar</string>
@@ -59,6 +59,8 @@
     <string name="button__filter">Filtrar</string>
 
     <!-- Merchants & Tellers -->
+    <string name="title_merchants">Comerciantes</string>
+    <string name="title_tellers">Tellers</string>
     <string name="msg__location_permission_necessary">El permiso de localización es necesario para mostrar tu ubicación actual en el mapa.</string>
 
     <!-- Send Transaction -->

app/src/main/res/values/strings.xml

@@ -36,7 +36,7 @@
 
     <!-- Home -->
     <string name="title_transactions">Transactions</string>
-    <string name="title_merchants">Merchants &amp; Tellers</string>
+    <string name="title_merchants_and_tellers">Merchants &amp; Tellers</string>
     <string name="title_receive">Receive</string>
     <string name="title_balances">Balances</string>
     <string name="title_send">Send</string>
@@ -59,6 +59,8 @@
     <string name="button__filter">Filter</string>
 
     <!-- Merchants & Tellers -->
+    <string name="title_merchants">Merchants</string>
+    <string name="title_tellers">Tellers</string>
     <string name="msg__location_permission_necessary">Location permission is necessary to show your current location on the map.</string>
 
     <!-- Send Transaction -->