Added a database to migrate entry storage to later; added checks to determine whether existing entries need to be migrated from preference storage to database

app/src/main/AndroidManifest.xml

@@ -19,7 +19,6 @@
             android:windowSoftInputMode="adjustPan">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
-
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>

app/src/main/java/com/denizd/textbasic/db/AppDatabase.kt

@@ -0,0 +1,57 @@
+package com.denizd.textbasic.db
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import com.denizd.textbasic.model.Entry
+
+/**
+ * Room database that holds all objects that need to be saved to persistent storage.
+ */
+@Database(
+    entities = [
+        Entry::class,
+    ],
+    version = 1,
+    exportSchema = true,
+)
+abstract class AppDatabase : RoomDatabase() {
+
+    /**
+     * The database access object. Database transactions go through this.
+     */
+    abstract fun dao(): EntryDao
+
+    companion object {
+        // The singular instance of this database
+        private var instance: AppDatabase? = null
+
+        /**
+         * Retrieve the instance of the database.
+         *
+         * @param context   used to resolve the object
+         * @return          the database
+         */
+        fun getInstance(context: Context): AppDatabase {
+            /*
+             * Check if an object has already been instantiated. Only create a new instance if none
+             * exists.
+             */
+            if (instance == null) {
+                synchronized(AppDatabase::class) {
+                    instance = Room
+                        .databaseBuilder(
+                            context.applicationContext,
+                            AppDatabase::class.java,
+                            "text_basic_db",
+                        )
+//                        .fallbackToDestructiveMigration()
+                        .build()
+                }
+            }
+            // Instance can never be null at this point
+            return instance!!
+        }
+    }
+}

app/src/main/java/com/denizd/textbasic/db/EntryDao.kt

@@ -0,0 +1,20 @@
+package com.denizd.textbasic.db
+
+import androidx.lifecycle.LiveData
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.Query
+import com.denizd.textbasic.model.Entry
+
+@Dao
+interface EntryDao {
+
+    @Query("SELECT * FROM entries ORDER BY position")
+    fun getAllEntries(): LiveData<List<Entry>>
+
+    @Insert
+    fun insertEntries(newEntries: List<Entry>)
+
+    @Query("DELETE FROM entries")
+    fun deleteAllEntries()
+}

app/src/main/java/com/denizd/textbasic/db/QuoteStorage.kt

@@ -6,6 +6,8 @@ import com.denizd.textbasic.util.SettingsPreference
 
 class QuoteStorage private constructor(context: Context) {
 
+    private val dao: EntryDao = AppDatabase.getInstance(context).dao()
+
     companion object {
 
         private lateinit var storage: QuoteStorage
@@ -26,8 +28,6 @@ class QuoteStorage private constructor(context: Context) {
         private const val KEY_QUOTES = "quotes"
         private const val KEY_QUOTE_COUNTER = "quotecounter"
         const val KEY_TEXT_SIZE = "textsize"
-        private const val KEY_INVERTED = "inverted"
-        private const val KEY_HIGH_CONTRAST = "hicontrast"
         const val KEY_TEXT_TRANSPARENCY = "transparency_text"
         const val KEY_BG_TRANSPARENCY = "transparency"
         private const val KEY_RANDOM = "random"
@@ -37,7 +37,6 @@ class QuoteStorage private constructor(context: Context) {
         private const val KEY_TYPEFACE_STYLE = "typefacestyle"
         private const val KEY_AVG_WIDTH = "avgwidth"
         private const val KEY_AVG_HEIGHT = "avgheight"
-        private const val KEY_OUTLINE_SIZE = "outlinesize"
         const val KEY_OUTLINE_SIZE_NEW = "outlinesizeint"
     }
 
@@ -131,4 +130,13 @@ class QuoteStorage private constructor(context: Context) {
             .putString(KEY_QUOTES, quotes.joinToString(SEPARATOR.toString()))
             .apply()
     }
+
+    fun needsMigration(): Boolean = prefs.getBoolean(SettingsPreference.NEEDS_MIGRATION.key, true)
+    fun migrateEntries() {
+        // TODO migrate entries
+        prefs.edit().putBoolean(SettingsPreference.NEEDS_MIGRATION.key, false).apply()
+    }
+    fun noMigrationNecessary() {
+        prefs.edit().putBoolean(SettingsPreference.NEEDS_MIGRATION.key, false).apply()
+    }
 }

app/src/main/java/com/denizd/textbasic/fragment/QuoteFragment.kt

@@ -23,6 +23,15 @@ class QuoteFragment : BaseFragment(R.layout.fragment_quote), QuoteAdapter.OnDele
         super.onViewCreated(view, savedInstanceState)
 
         storage = QuoteStorage.getInstance(context)
+
+        if (storage.getAllQuotes().isEmpty()) {
+            storage.noMigrationNecessary()
+        }
+
+        if (storage.needsMigration()) {
+            storage.migrateEntries()
+        }
+
         quoteAdapter = QuoteAdapter(storage.getAllQuotes(), this)
 
         binding.recyclerView.layoutManager = LinearLayoutManager(context)

app/src/main/java/com/denizd/textbasic/model/Entry.kt

@@ -0,0 +1,14 @@
+package com.denizd.textbasic.model
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+/**
+ * Stores a single entry. For use with a Room database.
+ */
+@Entity(tableName = "entries")
+data class Entry(
+    @PrimaryKey val id: Int,
+    val text: String,
+    val position: Int,
+)

app/src/main/java/com/denizd/textbasic/model/Quote.kt

@@ -1,6 +0,0 @@
-package com.denizd.textbasic.model
-
-/**
- * Stores a single quote. For potential use with a Room database.
- */
-data class Quote(val id: Int, var text: String)

app/src/main/java/com/denizd/textbasic/util/SettingsPreference.kt

@@ -4,10 +4,11 @@ import com.denizd.textbasic.db.QuoteStorage
 
 enum class SettingsPreference(val key: String) {
     TEXT_SIZE(QuoteStorage.KEY_TEXT_SIZE),
-    TEXT_TRANSPARENCY(QuoteStorage.KEY_TEXT_TRANSPARENCY),
     TEXT_COLOUR("textcolour"),
     HIGHLIGHT_INTENSITY(QuoteStorage.KEY_OUTLINE_SIZE_NEW),
-    HIGHLIGHT_TRANSPARENCY(QuoteStorage.KEY_BG_TRANSPARENCY),
     HIGHLIGHT_COLOUR("highlightcolour"),
+
+    // Whether a migration from preference storage to Room is needed for the entries
+    NEEDS_MIGRATION("needs_migration"),
     ;
 }