Added a singleton pattern to the DataManager

Author: appleobject

app/build.gradle

@@ -13,6 +13,7 @@ android {
         versionCode 1
         versionName "1.0"
 
+        vectorDrawables.useSupportLibrary = true
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
 

app/src/main/AndroidManifest.xml

@@ -10,15 +10,19 @@
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
         <activity
-            android:name=".MainActivity"
-            android:label="@string/app_name"
+            android:name=".NoteListActivity"
+            android:label="@string/title_activity_note_list"
             android:theme="@style/AppTheme.NoActionBar">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <activity
+            android:name=".MainActivity"
+            android:label="@string/edit_note_activity"
+            android:theme="@style/AppTheme.NoActionBar"/>
     </application>
 
 </manifest>

app/src/main/java/com/appleobject/notekeeper/MainActivity.kt

@@ -17,9 +17,8 @@ class MainActivity : AppCompatActivity() {
         setContentView(R.layout.activity_main)
         setSupportActionBar(findViewById(R.id.toolbar))
 
-        val dm = DataManager()
         val adapterCourses = ArrayAdapter<CourseInfo>(this,
-            android.R.layout.simple_spinner_item, dm.courses.values.toList())
+            android.R.layout.simple_spinner_item, DataManager.courses.values.toList())
         adapterCourses.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
         spinnerCourses.adapter = adapterCourses
 

app/src/main/java/com/appleobject/notekeeper/NoteListActivity.kt

@@ -0,0 +1,22 @@
+package com.appleobject.notekeeper
+
+import android.content.Intent
+import android.os.Bundle
+import com.google.android.material.floatingactionbutton.FloatingActionButton
+import com.google.android.material.snackbar.Snackbar
+import androidx.appcompat.app.AppCompatActivity
+import kotlinx.android.synthetic.main.activity_note_list.*
+
+class NoteListActivity : AppCompatActivity() {
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_note_list)
+        setSupportActionBar(findViewById(R.id.toolbar))
+
+        fabNoteList.setOnClickListener { view ->
+            val activityIntent = Intent(this, MainActivity::class.java)
+            startActivity(activityIntent)
+        }
+    }
+}

app/src/main/java/com/appleobject/notekeeper/model/DataManager.kt

@@ -1,11 +1,12 @@
 package com.appleobject.notekeeper.model
 
-class DataManager {
+object DataManager {
     val courses = HashMap<String, CourseInfo>()
     val notes = ArrayList<NoteInfo>()
 
     init {
         initializeCourses()
+        initializeNotes()
     }
 
     private fun initializeCourses(){
@@ -21,4 +22,8 @@ class DataManager {
         course = CourseInfo("java_core", "Java Fundamentals: The Core Platform")
         courses.set(course.courseId, course)
     }
+
+    private fun initializeNotes(){
+
+    }
 }

app/src/main/res/drawable/ic_white_add_24.xml

@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#FFFFFF"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M19,13h-6v6h-2v-6H5v-2h6V5h2v6h6v2z"/>
+</vector>

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

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<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"
+    app:layout_behavior="@string/appbar_scrolling_view_behavior">
+
+    <ListView
+        android:id="@+id/listNote"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        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/values/strings.xml

@@ -2,13 +2,12 @@
     <string name="app_name">NoteKeeper</string>
     <string name="action_settings">Settings</string>
     <!-- Strings used for fragments for navigation -->
-    <string name="first_fragment_label">First Fragment</string>
-    <string name="second_fragment_label">Second Fragment</string>
     <string name="next">Next</string>
     <string name="previous">Previous</string>
 
-    <string name="hello_first_fragment">Hello first fragment</string>
-    <string name="hello_second_fragment">Hello second fragment. Arg: %1$s</string>
+
     <string name="note_title">Note title</string>
     <string name="note_text">Note text</string>
+    <string name="title_activity_note_list">NoteKeeper</string>
+    <string name="edit_note_activity">Edit Note</string>
 </resources>