feat(ui): BuddyActivity

app/build.gradle

@@ -25,10 +25,12 @@ android {
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
     implementation 'androidx.appcompat:appcompat:1.1.0'
     implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
     implementation 'com.google.android.material:material:1.0.0'
+    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
+    implementation 'androidx.recyclerview:recyclerview:1.0.0'
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'androidx.test:runner:1.2.0'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'

app/src/main/AndroidManifest.xml

@@ -14,6 +14,24 @@
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
         <activity
+            android:name=".BuddyListActivity"
+            android:label="@string/title_buddy_list"
+            android:parentActivityName=".ui.FriendsActivity"
+            android:theme="@style/AppTheme.NoActionBar">
+            <meta-data
+                android:name="android.support.PARENT_ACTIVITY"
+                android:value="fr.plnech.dunbar.ui.FriendsActivity" />
+        </activity>
+        <activity
+            android:name=".BuddyDetailActivity"
+            android:label="@string/title_buddy_detail"
+            android:parentActivityName=".BuddyListActivity"
+            android:theme="@style/AppTheme.NoActionBar">
+            <meta-data
+                android:name="android.support.PARENT_ACTIVITY"
+                android:value="fr.plnech.dunbar.BuddyListActivity" />
+        </activity>
+        <activity
             android:name=".ui.FriendsActivity"
             android:label="@string/app_name"
             android:theme="@style/AppTheme.NoActionBar">
@@ -24,4 +42,5 @@
             </intent-filter>
         </activity>
     </application>
+
 </manifest>
\ No newline at end of file

app/src/main/java/fr/plnech/dunbar/BuddyDetailActivity.kt

+package fr.plnech.dunbar
+
+import android.content.Intent
+import android.os.Bundle
+import com.google.android.material.snackbar.Snackbar
+import androidx.appcompat.app.AppCompatActivity
+import android.view.MenuItem
+import kotlinx.android.synthetic.main.activity_buddy_detail.*
+
+/**
+ * An activity representing a single Buddy detail screen. This
+ * activity is only used on narrow width devices. On tablet-size devices,
+ * item details are presented side-by-side with a list of items
+ * in a [BuddyListActivity].
+ */
+class BuddyDetailActivity : AppCompatActivity() {
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_buddy_detail)
+        setSupportActionBar(detail_toolbar)
+
+        fab.setOnClickListener { view ->
+            Snackbar.make(view, "Replace with your own detail action", Snackbar.LENGTH_LONG)
+                .setAction("Action", null).show()
+        }
+
+        // Show the Up button in the action bar.
+        supportActionBar?.setDisplayHomeAsUpEnabled(true)
+
+        // savedInstanceState is non-null when there is fragment state
+        // saved from previous configurations of this activity
+        // (e.g. when rotating the screen from portrait to landscape).
+        // In this case, the fragment will automatically be re-added
+        // to its container so we don't need to manually add it.
+        // For more information, see the Fragments API guide at:
+        //
+        // http://developer.android.com/guide/components/fragments.html
+        //
+        if (savedInstanceState == null) {
+            // Create the detail fragment and add it to the activity
+            // using a fragment transaction.
+            val fragment = BuddyDetailFragment().apply {
+                arguments = Bundle().apply {
+                    putString(
+                        BuddyDetailFragment.ARG_ITEM_ID,
+                        intent.getStringExtra(BuddyDetailFragment.ARG_ITEM_ID)
+                    )
+                }
+            }
+
+            supportFragmentManager.beginTransaction()
+                .add(R.id.buddy_detail_container, fragment)
+                .commit()
+        }
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem) =
+        when (item.itemId) {
+            android.R.id.home -> {
+                // This ID represents the Home or Up button. In the case of this
+                // activity, the Up button is shown. For
+                // more details, see the Navigation pattern on Android Design:
+                //
+                // http://developer.android.com/design/patterns/navigation.html#up-vs-back
+
+                navigateUpTo(Intent(this, BuddyListActivity::class.java))
+                true
+            }
+            else -> super.onOptionsItemSelected(item)
+        }
+}

app/src/main/java/fr/plnech/dunbar/BuddyDetailFragment.kt

+package fr.plnech.dunbar
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import fr.plnech.dunbar.dummy.DummyContent
+import fr.plnech.dunbar.model.Friend
+import kotlinx.android.synthetic.main.activity_buddy_detail.*
+import kotlinx.android.synthetic.main.buddy_detail.view.*
+
+/**
+ * A fragment representing a single Buddy detail screen.
+ * This fragment is either contained in a [BuddyListActivity]
+ * in two-pane mode (on tablets) or a [BuddyDetailActivity]
+ * on handsets.
+ */
+class BuddyDetailFragment : Fragment() {
+
+    /**
+     * The dummy content this fragment is presenting.
+     */
+    private var item: Friend? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        arguments?.let {
+            if (it.containsKey(ARG_ITEM_ID)) {
+                // Load the dummy content specified by the fragment
+                // arguments. In a real-world scenario, use a Loader
+                // to load content from a content provider.
+                item = DummyContent.ITEM_MAP[it.getInt(ARG_ITEM_ID)]
+                activity?.toolbar_layout?.title = item?.name
+            }
+        }
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        val rootView = inflater.inflate(R.layout.buddy_detail, container, false)
+
+        // Show the dummy content as text in a TextView.
+        item?.let {
+            rootView.buddy_detail.text = it.mapString()
+            activity?.title = it.name
+        }
+
+        return rootView
+    }
+
+    companion object {
+        /**
+         * The fragment argument representing the item ID that this fragment
+         * represents.
+         */
+        const val ARG_ITEM_ID = "item_id"
+    }
+}

app/src/main/java/fr/plnech/dunbar/BuddyListActivity.kt

+package fr.plnech.dunbar
+
+import android.content.Intent
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.MenuItem
+import android.view.View
+import android.view.ViewGroup
+import android.widget.TextView
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.app.NavUtils
+import androidx.recyclerview.widget.RecyclerView
+import com.google.android.material.snackbar.Snackbar
+import fr.plnech.dunbar.dummy.DummyContent
+import fr.plnech.dunbar.model.Friend
+import kotlinx.android.synthetic.main.activity_buddy_list.*
+import kotlinx.android.synthetic.main.buddy_list.*
+import kotlinx.android.synthetic.main.buddy_list_content.view.*
+
+class BuddyListActivity : AppCompatActivity() {
+
+    /**
+     * Whether or not the activity is in two-pane mode, i.e. running on a tablet
+     * device.
+     */
+    private var twoPane: Boolean = false
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_buddy_list)
+
+        setSupportActionBar(toolbar)
+        toolbar.title = title
+
+        fab.setOnClickListener { view ->
+            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
+                .setAction("Action", null).show()
+        }
+        // Show the Up button in the action bar.
+        supportActionBar?.setDisplayHomeAsUpEnabled(true)
+
+        if (buddy_detail_container != null) {
+            // The detail container view will be present only in the
+            // large-screen layouts (res/values-w900dp).
+            // If this view is present, then the
+            // activity should be in two-pane mode.
+            twoPane = true
+        }
+
+        setupRecyclerView(buddy_list)
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem) =
+        when (item.itemId) {
+            android.R.id.home -> {
+                NavUtils.navigateUpFromSameTask(this)
+                true
+            }
+            else -> super.onOptionsItemSelected(item)
+        }
+
+    private fun setupRecyclerView(recyclerView: RecyclerView) {
+        recyclerView.adapter = SimpleItemRecyclerViewAdapter(this, DummyContent.ITEMS, twoPane)
+    }
+
+    class SimpleItemRecyclerViewAdapter(
+        private val parentActivity: BuddyListActivity,
+        private val values: List<Friend>,
+        private val twoPane: Boolean
+    ) :
+        RecyclerView.Adapter<SimpleItemRecyclerViewAdapter.ViewHolder>() {
+
+        private val onClickListener: View.OnClickListener
+
+        init {
+            onClickListener = View.OnClickListener { v ->
+                val item = v.tag as Friend
+                if (twoPane) {
+                    val fragment = BuddyDetailFragment().apply {
+                        arguments = Bundle().apply {
+                            putString(BuddyDetailFragment.ARG_ITEM_ID, "friend_${item.id}")
+                        }
+                    }
+                    parentActivity.supportFragmentManager
+                        .beginTransaction()
+                        .replace(R.id.buddy_detail_container, fragment)
+                        .commit()
+                } else {
+                    val intent = Intent(v.context, BuddyDetailActivity::class.java).apply {
+                        putExtra(BuddyDetailFragment.ARG_ITEM_ID, "friend_${item.id}")
+                    }
+                    v.context.startActivity(intent)
+                }
+            }
+        }
+
+        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
+            val view = LayoutInflater.from(parent.context)
+                .inflate(R.layout.buddy_list_content, parent, false)
+            return ViewHolder(view)
+        }
+
+        override fun onBindViewHolder(holder: ViewHolder, position: Int) {
+            val item = values[position]
+            holder.idView.text = item.name
+            holder.contentView.text = item.mapString()
+
+            with(holder.itemView) {
+                tag = item
+                setOnClickListener(onClickListener)
+            }
+        }
+
+        override fun getItemCount() = values.size
+
+        inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
+            val idView: TextView = view.id_text
+            val contentView: TextView = view.content
+        }
+    }
+}

app/src/main/java/fr/plnech/dunbar/Extensions.kt

@@ -15,7 +15,8 @@ fun String.plural(count: Int = 1): String {
     }
 }
 
-fun Context.fetchFriends(): List<Friend> {
+fun Context.fetchFriends(includeNot: Boolean = true): List<Friend> {
+    // TODO: https://developer.android.com/training/permissions/requesting
     val friends = mutableListOf<Friend>()
 
     //TODO: More efficient query using non-null parameters
@@ -42,7 +43,10 @@ fun Context.fetchFriends(): List<Friend> {
         it.close()
     }
 
-    return friends.sortedByDescending { it.timesContacted }
+    println("Fetched ${friends.size} friends.")
+
+    return (if (includeNot) friends else friends.filter { it.lastDate != null })
+        .sortedByDescending { it.timesContacted }
 }
 
 
@@ -66,6 +70,5 @@ private fun Context.getFriendPhoto(id: Long): Bitmap? {
     } catch (e: IOException) {
         e.printStackTrace()
     }
-    println("Photo for $id: $photo")
     return photo
 }
\ No newline at end of file

app/src/main/java/fr/plnech/dunbar/dummy/DummyContent.kt

+package fr.plnech.dunbar.dummy
+
+import android.provider.ContactsContract
+import fr.plnech.dunbar.model.Friend
+import java.util.*
+
+/**
+ * Helper class for providing sample content for user interfaces created by
+ * Android template wizards.
+ *
+ * TODO: Replace all uses of this class before publishing your app.
+ */
+object DummyContent {
+
+    /**
+     * An array of sample (dummy) items.
+     */
+    val ITEMS: MutableList<Friend> = ArrayList()
+
+    /**
+     * A map of sample (dummy) items, by ID.
+     */
+    val ITEM_MAP: MutableMap<Int, Friend> = HashMap()
+
+    private val COUNT = 25
+
+    init {
+        // Add some sample items.
+        for (i in 1..COUNT) {
+            addItem(createFriend(i))
+        }
+    }
+
+    private fun addItem(item: Friend) {
+        ITEMS.add(item)
+        ITEM_MAP[item.id] = item
+    }
+
+    private fun createFriend(position: Int): Friend {
+        return Friend(
+            mapOf(
+                ContactsContract.Contacts._ID to "$position",
+                ContactsContract.Contacts.DISPLAY_NAME to "Friend $position",
+                "data1" to "01 23 45 67 89",
+                "details" to "$position: this friend has a lot of details about them. What do you think?"
+            )
+        )
+    }
+}

app/src/main/java/fr/plnech/dunbar/model/Friend.kt

@@ -6,7 +6,7 @@ import android.net.Uri
 import android.provider.ContactsContract.Contacts
 import java.util.*
 
-data class Friend(val map: MutableMap<String, String?>, val photo: Bitmap?) {
+data class Friend(val map: Map<String, String?> = mutableMapOf(), val photo: Bitmap? = null) {
     override fun toString(): String = "$name"
 
     fun mapString(): String = map.entries.filter { !it.value.isNullOrEmpty() }.toString()
@@ -23,11 +23,12 @@ data class Friend(val map: MutableMap<String, String?>, val photo: Bitmap?) {
     val phone: String?
         get() = if (map[Contacts.HAS_PHONE_NUMBER] == "1") map["data1"] else null
 
-    val lastTimeStamp = map[Contacts.LAST_TIME_CONTACTED]!!.toLong()
+    val lastTimeStamp = map[Contacts.LAST_TIME_CONTACTED]?.toLong() ?: 0
 
     val lastDate: Date?
         get() = if (lastTimeStamp > 0) Date(lastTimeStamp) else null
 
+    //FIXME: Broken on AndroidQ. Use messages / phone log
     val timesContacted: Int
         get() = map[Contacts.TIMES_CONTACTED]?.toInt() ?: 0
 
@@ -51,7 +52,5 @@ data class Friend(val map: MutableMap<String, String?>, val photo: Bitmap?) {
             Intent(Intent.ACTION_DIAL, Uri.parse("tel:${it}"))
         }
     }
-
-
 }
 

app/src/main/java/fr/plnech/dunbar/ui/FriendsActivity.kt

 package fr.plnech.dunbar.ui
 
+import android.content.Intent
 import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
@@ -7,6 +8,7 @@ import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.app.NotificationManagerCompat
 import androidx.recyclerview.widget.LinearLayoutManager
+import fr.plnech.dunbar.BuddyListActivity
 import fr.plnech.dunbar.R
 import fr.plnech.dunbar.data.Messages
 import fr.plnech.dunbar.fetchFriends
@@ -74,6 +76,10 @@ class FriendsActivity : AppCompatActivity() {
         // as you specify a parent activity in AndroidManifest.xml.
         return when (item.itemId) {
             R.id.action_settings -> true
+            R.id.action_buddies -> {
+                startActivity(Intent(this, BuddyListActivity::class.java))
+                true
+            }
             else -> super.onOptionsItemSelected(item)
         }
     }

app/src/main/java/fr/plnech/dunbar/ui/FriendsAdapter.kt

@@ -69,9 +69,7 @@ class FriendsViewHolder(private val view: View) : RecyclerView.ViewHolder(view)
     }
 
     private fun bindPic(friend: Friend) {
-        friend.photo?.let {
-            pic.setImageBitmap(it)
-        }
+        pic.setImageBitmap(friend.photo)
     }
 
     private fun bindPhone(friend: Friend) {

app/src/main/res/layout-w900dp/buddy_list.xml

+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:layout_marginLeft="16dp"
+    android:layout_marginRight="16dp"
+    android:baselineAligned="false"
+    android:divider="?android:attr/dividerHorizontal"
+    android:orientation="horizontal"
+    android:showDividers="middle"
+    tools:context=".BuddyListActivity">
+
+    <!--
+    This layout is a two-pane layout for the Buddies
+    master/detail flow.
+    
+    -->
+
+    <androidx.recyclerview.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:tools="http://schemas.android.com/tools"
+        android:id="@+id/buddy_list"
+        android:name="fr.plnech.dunbar.BuddyListFragment"
+        android:layout_width="@dimen/item_width"
+        android:layout_height="match_parent"
+        android:layout_marginLeft="16dp"
+        android:layout_marginRight="16dp"
+        app:layoutManager="LinearLayoutManager"
+        tools:context="fr.plnech.dunbar.BuddyListActivity"
+        tools:listitem="@layout/buddy_list_content" />
+
+    <FrameLayout
+        android:id="@+id/buddy_detail_container"
+        android:layout_width="0dp"
+        android:layout_height="match_parent"
+        android:layout_weight="3" />
+
+</LinearLayout>
\ No newline at end of file

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

+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:fitsSystemWindows="true"
+    tools:context=".BuddyDetailActivity"
+    tools:ignore="MergeRootFrame">
+
+    <com.google.android.material.appbar.AppBarLayout
+        android:id="@+id/app_bar"
+        android:layout_width="match_parent"
+        android:layout_height="@dimen/app_bar_height"
+        android:fitsSystemWindows="true"
+        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
+
+        <com.google.android.material.appbar.CollapsingToolbarLayout
+            android:id="@+id/toolbar_layout"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:fitsSystemWindows="true"
+            app:contentScrim="?attr/colorPrimary"
+            app:layout_scrollFlags="scroll|exitUntilCollapsed"
+            app:toolbarId="@+id/toolbar">
+
+            <androidx.appcompat.widget.Toolbar
+                android:id="@+id/detail_toolbar"
+                android:layout_width="match_parent"
+                android:layout_height="?attr/actionBarSize"
+                app:layout_collapseMode="pin"
+                app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
+
+        </com.google.android.material.appbar.CollapsingToolbarLayout>
+
+    </com.google.android.material.appbar.AppBarLayout>
+
+    <androidx.core.widget.NestedScrollView
+        android:id="@+id/buddy_detail_container"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        app:layout_behavior="@string/appbar_scrolling_view_behavior" />
+
+    <com.google.android.material.floatingactionbutton.FloatingActionButton
+        android:id="@+id/fab"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_vertical|start"
+        android:layout_margin="@dimen/fab_margin"
+        app:layout_anchor="@+id/buddy_detail_container"
+        app:layout_anchorGravity="top|end"
+        app:srcCompat="@android:drawable/stat_notify_chat" />
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
\ No newline at end of file

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

+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:fitsSystemWindows="true"
+    tools:context=".BuddyListActivity">
+
+    <com.google.android.material.appbar.AppBarLayout
+        android:id="@+id/app_bar"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:theme="@style/AppTheme.AppBarOverlay">
+
+        <androidx.appcompat.widget.Toolbar
+            android:id="@+id/toolbar"
+            android:layout_width="match_parent"
+            android:layout_height="?attr/actionBarSize"
+            app:popupTheme="@style/AppTheme.PopupOverlay" />
+
+    </com.google.android.material.appbar.AppBarLayout>
+
+    <FrameLayout
+        android:id="@+id/frameLayout"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        app:layout_behavior="@string/appbar_scrolling_view_behavior">
+
+        <include layout="@layout/buddy_list" />
+    </FrameLayout>
+
+    <com.google.android.material.floatingactionbutton.FloatingActionButton
+        android:id="@+id/fab"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="bottom|end"
+        android:layout_margin="@dimen/fab_margin"
+        app:srcCompat="@android:drawable/ic_dialog_email" />
+
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
\ No newline at end of file

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

+<?xml version="1.0" encoding="utf-8"?>
+<TextView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/buddy_detail"
+    style="?android:attr/textAppearanceLarge"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:padding="16dp"
+    android:textIsSelectable="true"
+    tools:context=".BuddyDetailFragment" />
\ No newline at end of file

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

+<?xml version="1.0" encoding="utf-8"?>
+<androidx.recyclerview.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/buddy_list"
+    android:name="fr.plnech.dunbar.BuddyListFragment"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:layout_marginLeft="16dp"
+    android:layout_marginRight="16dp"
+    app:layoutManager="LinearLayoutManager"
+    tools:context=".BuddyListActivity"
+    tools:listitem="@layout/buddy_list_content" />
\ No newline at end of file

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

+<?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"
+    android:orientation="horizontal">
+
+    <TextView
+        android:id="@+id/id_text"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_margin="@dimen/text_margin"
+        android:textAppearance="?attr/textAppearanceListItem" />
+
+    <TextView
+        android:id="@+id/content"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_margin="@dimen/text_margin"
+        android:textAppearance="?attr/textAppearanceListItem" />
+</LinearLayout>
\ No newline at end of file

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

@@ -26,6 +26,7 @@
         android:id="@+id/friendsList"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
+        android:scrollbars="vertical"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent"

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

@@ -3,6 +3,11 @@
     xmlns:tools="http://schemas.android.com/tools"
     tools:context="fr.plnech.dunbar.ui.FriendsActivity">
     <item
+        android:id="@+id/action_buddies"
+        android:orderInCategory="100"
+        android:title="@string/action_buddies"
+        app:showAsAction="ifRoom" />
+    <item
         android:id="@+id/action_settings"
         android:orderInCategory="100"
         android:title="@string/action_settings"

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

 <resources>
     <dimen name="fab_margin">16dp</dimen>
+    <dimen name="app_bar_height">200dp</dimen>
+    <dimen name="item_width">200dp</dimen>
+    <dimen name="text_margin">16dp</dimen>
 </resources>

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

@@ -3,4 +3,7 @@
     <string name="channel_name">Dunbar</string>
     <string name="channel_description">Updates about friends you don\'t want to forget</string>
     <string name="action_settings">Settings</string>
+    <string name="action_buddies">Buddies</string>
+    <string name="title_buddy_list">Buddies</string>
+    <string name="title_buddy_detail">Buddy Detail</string>
 </resources>