All the nav buttons are there now, successfully compiles.

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/MainActivity.java

@@ -20,7 +20,8 @@ public class MainActivity extends AppCompatActivity {
         // Passing each menu ID as a set of Ids because each
         // menu should be considered as top level destinations.
         AppBarConfiguration appBarConfiguration = new AppBarConfiguration.Builder(
-                R.id.navigation_home, R.id.navigation_dashboard, R.id.navigation_notifications)
+                R.id.navigation_tacnet, R.id.navigation_editor, R.id.navigation_settings,
+                R.id.navigation_search)
                 .build();
         NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
         NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/TACNETFragment.java

@@ -1,64 +0,0 @@
-package org.timecrafters.TimeCraftersConfigurationTool;
-
-import android.os.Bundle;
-
-import androidx.fragment.app.Fragment;
-
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-
-/**
- * A simple {@link Fragment} subclass.
- * Use the {@link TACNETFragment#newInstance} factory method to
- * create an instance of this fragment.
- */
-public class TACNETFragment extends Fragment {
-
-    // TODO: Rename parameter arguments, choose names that match
-    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
-    private static final String ARG_PARAM1 = "param1";
-    private static final String ARG_PARAM2 = "param2";
-
-    // TODO: Rename and change types of parameters
-    private String mParam1;
-    private String mParam2;
-
-    public TACNETFragment() {
-        // Required empty public constructor
-    }
-
-    /**
-     * Use this factory method to create a new instance of
-     * this fragment using the provided parameters.
-     *
-     * @param param1 Parameter 1.
-     * @param param2 Parameter 2.
-     * @return A new instance of fragment TACNETFragment.
-     */
-    // TODO: Rename and change types and number of parameters
-    public static TACNETFragment newInstance(String param1, String param2) {
-        TACNETFragment fragment = new TACNETFragment();
-        Bundle args = new Bundle();
-        args.putString(ARG_PARAM1, param1);
-        args.putString(ARG_PARAM2, param2);
-        fragment.setArguments(args);
-        return fragment;
-    }
-
-    @Override
-    public void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        if (getArguments() != null) {
-            mParam1 = getArguments().getString(ARG_PARAM1);
-            mParam2 = getArguments().getString(ARG_PARAM2);
-        }
-    }
-
-    @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
-                             Bundle savedInstanceState) {
-        // Inflate the layout for this fragment
-        return inflater.inflate(R.layout.fragment_tacnet, container, false);
-    }
-}

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/editor/EditorFragment.java

@@ -1,4 +1,4 @@
-package org.timecrafters.TimeCraftersConfigurationTool.ui.home;
+package org.timecrafters.TimeCraftersConfigurationTool.ui.editor;
 
 import android.os.Bundle;
 import android.view.LayoutInflater;
@@ -14,17 +14,17 @@ import androidx.lifecycle.ViewModelProviders;
 
 import org.timecrafters.TimeCraftersConfigurationTool.R;
 
-public class HomeFragment extends Fragment {
+public class EditorFragment extends Fragment {
 
-    private HomeViewModel homeViewModel;
+    private EditorViewModel editorViewModel;
 
     public View onCreateView(@NonNull LayoutInflater inflater,
                              ViewGroup container, Bundle savedInstanceState) {
-        homeViewModel =
-                ViewModelProviders.of(this).get(HomeViewModel.class);
-        View root = inflater.inflate(R.layout.fragment_home, container, false);
-        final TextView textView = root.findViewById(R.id.text_home);
-        homeViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
+        editorViewModel =
+                ViewModelProviders.of(this).get(EditorViewModel.class);
+        View root = inflater.inflate(R.layout.fragment_editor, container, false);
+        final TextView textView = root.findViewById(R.id.text_editor);
+        editorViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
             @Override
             public void onChanged(@Nullable String s) {
                 textView.setText(s);

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/editor/EditorViewModel.java

@@ -1,16 +1,16 @@
-package org.timecrafters.TimeCraftersConfigurationTool.ui.home;
+package org.timecrafters.TimeCraftersConfigurationTool.ui.editor;
 
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.ViewModel;
 
-public class HomeViewModel extends ViewModel {
+public class EditorViewModel extends ViewModel {
 
     private MutableLiveData<String> mText;
 
-    public HomeViewModel() {
+    public EditorViewModel() {
         mText = new MutableLiveData<>();
-        mText.setValue("This is home fragment");
+        mText.setValue("This is editor fragment");
     }
 
     public LiveData<String> getText() {

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/search/SearchFragment.java

@@ -1,4 +1,4 @@
-package org.timecrafters.TimeCraftersConfigurationTool.ui.dashboard;
+package org.timecrafters.TimeCraftersConfigurationTool.ui.search;
 
 import android.os.Bundle;
 import android.view.LayoutInflater;
@@ -14,17 +14,17 @@ import androidx.lifecycle.ViewModelProviders;
 
 import org.timecrafters.TimeCraftersConfigurationTool.R;
 
-public class DashboardFragment extends Fragment {
+public class SearchFragment extends Fragment {
 
-    private DashboardViewModel dashboardViewModel;
+    private SearchViewModel searchViewModel;
 
     public View onCreateView(@NonNull LayoutInflater inflater,
                              ViewGroup container, Bundle savedInstanceState) {
-        dashboardViewModel =
-                ViewModelProviders.of(this).get(DashboardViewModel.class);
-        View root = inflater.inflate(R.layout.fragment_dashboard, container, false);
-        final TextView textView = root.findViewById(R.id.text_dashboard);
-        dashboardViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
+        searchViewModel =
+                ViewModelProviders.of(this).get(SearchViewModel.class);
+        View root = inflater.inflate(R.layout.fragment_search, container, false);
+        final TextView textView = root.findViewById(R.id.text_search);
+        searchViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
             @Override
             public void onChanged(@Nullable String s) {
                 textView.setText(s);

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/search/SearchViewModel.java

@@ -1,16 +1,16 @@
-package org.timecrafters.TimeCraftersConfigurationTool.ui.dashboard;
+package org.timecrafters.TimeCraftersConfigurationTool.ui.search;
 
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.ViewModel;
 
-public class DashboardViewModel extends ViewModel {
+public class SearchViewModel extends ViewModel {
 
     private MutableLiveData<String> mText;
 
-    public DashboardViewModel() {
+    public SearchViewModel() {
         mText = new MutableLiveData<>();
-        mText.setValue("This is dashboard fragment");
+        mText.setValue("This is search fragment");
     }
 
     public LiveData<String> getText() {

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/settings/SettingsFragment.java

@@ -1,4 +1,4 @@
-package org.timecrafters.TimeCraftersConfigurationTool.ui.notifications;
+package org.timecrafters.TimeCraftersConfigurationTool.ui.settings;
 
 import android.os.Bundle;
 import android.view.LayoutInflater;
@@ -14,17 +14,17 @@ import androidx.lifecycle.ViewModelProviders;
 
 import org.timecrafters.TimeCraftersConfigurationTool.R;
 
-public class NotificationsFragment extends Fragment {
+public class SettingsFragment extends Fragment {
 
-    private NotificationsViewModel notificationsViewModel;
+    private SettingsViewModel settingsViewModel;
 
     public View onCreateView(@NonNull LayoutInflater inflater,
                              ViewGroup container, Bundle savedInstanceState) {
-        notificationsViewModel =
-                ViewModelProviders.of(this).get(NotificationsViewModel.class);
-        View root = inflater.inflate(R.layout.fragment_notifications, container, false);
-        final TextView textView = root.findViewById(R.id.text_notifications);
-        notificationsViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
+        settingsViewModel =
+                ViewModelProviders.of(this).get(SettingsViewModel.class);
+        View root = inflater.inflate(R.layout.fragment_settings, container, false);
+        final TextView textView = root.findViewById(R.id.text_settings);
+        settingsViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
             @Override
             public void onChanged(@Nullable String s) {
                 textView.setText(s);

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/settings/SettingsViewModel.java

@@ -1,16 +1,16 @@
-package org.timecrafters.TimeCraftersConfigurationTool.ui.notifications;
+package org.timecrafters.TimeCraftersConfigurationTool.ui.settings;
 
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.ViewModel;
 
-public class NotificationsViewModel extends ViewModel {
+public class SettingsViewModel extends ViewModel {
 
     private MutableLiveData<String> mText;
 
-    public NotificationsViewModel() {
+    public SettingsViewModel() {
         mText = new MutableLiveData<>();
-        mText.setValue("This is notifications fragment");
+        mText.setValue("This is settings fragment");
     }
 
     public LiveData<String> getText() {

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/tacnet/TACNETFragment.java

@@ -0,0 +1,35 @@
+package org.timecrafters.TimeCraftersConfigurationTool.ui.tacnet;
+
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.fragment.app.Fragment;
+import androidx.lifecycle.Observer;
+import androidx.lifecycle.ViewModelProviders;
+
+import org.timecrafters.TimeCraftersConfigurationTool.R;
+
+public class TACNETFragment extends Fragment {
+
+    private TACNETViewModel TACNETViewModel;
+
+    public View onCreateView(@NonNull LayoutInflater inflater,
+                             ViewGroup container, Bundle savedInstanceState) {
+        TACNETViewModel =
+                ViewModelProviders.of(this).get(TACNETViewModel.class);
+        View root = inflater.inflate(R.layout.fragment_tacnet, container, false);
+        final TextView textView = root.findViewById(R.id.text_tacnet);
+        TACNETViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
+            @Override
+            public void onChanged(@Nullable String s) {
+                textView.setText(s);
+            }
+        });
+        return root;
+    }
+}

app/src/main/java/org/timecrafters/TimeCraftersConfigurationTool/ui/tacnet/TACNETViewModel.java

@@ -0,0 +1,19 @@
+package org.timecrafters.TimeCraftersConfigurationTool.ui.tacnet;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+import androidx.lifecycle.ViewModel;
+
+public class TACNETViewModel extends ViewModel {
+
+    private MutableLiveData<String> mText;
+
+    public TACNETViewModel() {
+        mText = new MutableLiveData<>();
+        mText.setValue("This is TACNET fragment");
+    }
+
+    public LiveData<String> getText() {
+        return mText;
+    }
+}

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

@@ -4,10 +4,10 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".ui.dashboard.DashboardFragment">
+    tools:context=".ui.editor.EditorFragment">
 
     <TextView
-        android:id="@+id/text_dashboard"
+        android:id="@+id/text_editor"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_marginStart="8dp"

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

@@ -4,10 +4,10 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".ui.notifications.NotificationsFragment">
+    tools:context=".ui.search.SearchFragment">
 
     <TextView
-        android:id="@+id/text_notifications"
+        android:id="@+id/text_search"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_marginStart="8dp"

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

@@ -4,10 +4,10 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".ui.home.HomeFragment">
+    tools:context=".ui.settings.SettingsFragment">
 
     <TextView
-        android:id="@+id/text_home"
+        android:id="@+id/text_settings"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_marginStart="8dp"

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

@@ -1,14 +1,22 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout 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"
-    tools:context=".TACNETFragment">
+    tools:context=".ui.tacnet.TACNETFragment">
 
-    <!-- TODO: Update blank fragment layout -->
     <TextView
+        android:id="@+id/text_tacnet"
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:text="@string/hello_blank_fragment" />
-
-</FrameLayout>
+        android:layout_height="wrap_content"
+        android:layout_marginStart="8dp"
+        android:layout_marginTop="8dp"
+        android:layout_marginEnd="8dp"
+        android:textAlignment="center"
+        android:textSize="20sp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+</androidx.constraintlayout.widget.ConstraintLayout>

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

@@ -3,28 +3,28 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/mobile_navigation"
-    app:startDestination="@+id/navigation_home">
+    app:startDestination="@+id/navigation_editor">
+
+    <fragment
+        android:id="@+id/navigation_tacnet"
+        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.tacnet.TACNETFragment"
+        android:label="@string/title_tacnet"
+        tools:layout="@layout/fragment_tacnet" />
 
     <fragment
         android:id="@+id/navigation_editor"
-        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.home.HomeFragment"
-        android:label="@string/title_home"
-        tools:layout="@layout/fragment_home" />
+        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.editor.EditorFragment"
+        android:label="@string/title_editor"
+        tools:layout="@layout/fragment_editor" />
 
     <fragment
-        android:id="@+id/navigation_dashboard"
-        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.dashboard.DashboardFragment"
-        android:label="@string/title_dashboard"
-        tools:layout="@layout/fragment_dashboard" />
-
+        android:id="@+id/navigation_settings"
+        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.settings.SettingsFragment"
+        android:label="@string/title_settings"
+        tools:layout="@layout/fragment_settings" />
     <fragment
-        android:id="@+id/navigation_notifications"
-        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.notifications.NotificationsFragment"
-        android:label="@string/title_notifications"
-        tools:layout="@layout/fragment_notifications" />
-    <fragment
-        android:id="@+id/TACNETFragment"
-        android:name="org.timecrafters.TimeCraftersConfigurationTool.TACNETFragment"
-        android:label="fragment_tacnet"
-        tools:layout="@layout/fragment_tacnet" />
+        android:id="@+id/navigation_search"
+        android:name="org.timecrafters.TimeCraftersConfigurationTool.ui.search.SearchFragment"
+        android:label="@string/title_search"
+        tools:layout="@layout/fragment_search" />
 </navigation>

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

@@ -1,9 +1,5 @@
 <resources>
     <string name="app_name">TimeCraftersConfigurationTool</string>
-    <string name="title_home">Home</string>
-    <string name="title_dashboard">Dashboard</string>
-    <string name="title_notifications">Notifications</string>
-    <!-- TODO: Remove or change this placeholder text -->
     <string name="hello_blank_fragment">Hello blank fragment</string>
     <string name="title_editor">Editor</string>
     <string name="title_search">Search</string>