Add categories to transactions

.project

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>MyAllowance</name>
+	<comment>Project MyAllowance created by Buildship.</comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

.settings/org.eclipse.buildship.core.prefs

@@ -0,0 +1,2 @@
+connection.project.dir=
+eclipse.preferences.version=1

app/.classpath

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8/"/>
+	<classpathentry kind="con" path="org.eclipse.buildship.core.gradleclasspathcontainer"/>
+	<classpathentry kind="output" path="bin/default"/>
+</classpath>

app/.project

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>app</name>
+	<comment>Project app created by Buildship.</comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

app/.settings/org.eclipse.buildship.core.prefs

@@ -0,0 +1,2 @@
+connection.project.dir=..
+eclipse.preferences.version=1

app/build.gradle

@@ -18,7 +18,7 @@ android {
     }
     defaultConfig {
         applicationId "com.wbrawner.budget"
-        minSdkVersion 23
+        minSdkVersion 24
         targetSdkVersion 27
         versionCode 1
         versionName "1.0"
@@ -29,6 +29,11 @@ android {
         buildConfigField "String", "ACRA_URL", "\"${acra.getProperty("url")}\""
         buildConfigField "String", "ACRA_USER", "\"${acra.getProperty("user")}\""
         buildConfigField "String", "ACRA_PASS", "\"${acra.getProperty("pass")}\""
+        javaCompileOptions {
+            annotationProcessorOptions {
+                arguments = ["room.schemaLocation": "$projectDir/schemas".toString()]
+            }
+        }
     }
     buildTypes {
         release {
@@ -36,6 +41,9 @@ android {
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
     }
+    sourceSets {
+        androidTest.assets.srcDirs += files("$projectDir/schemas".toString())
+    }
 }
 
 dependencies {

app/schemas/com.wbrawner.budget.data.BudgetDatabase/2.json

@@ -0,0 +1,113 @@
+{
+  "formatVersion": 1,
+  "database": {
+    "version": 2,
+    "identityHash": "b68fd456557e5153b2fe6514a5193c07",
+    "entities": [
+      {
+        "tableName": "Transaction",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER, `title` TEXT NOT NULL, `date` TEXT NOT NULL, `description` TEXT NOT NULL, `amount` REAL NOT NULL, `categoryId` INTEGER, `type` TEXT NOT NULL, PRIMARY KEY(`id`))",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": false
+          },
+          {
+            "fieldPath": "title",
+            "columnName": "title",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "date",
+            "columnName": "date",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "description",
+            "columnName": "description",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "amount",
+            "columnName": "amount",
+            "affinity": "REAL",
+            "notNull": true
+          },
+          {
+            "fieldPath": "categoryId",
+            "columnName": "categoryId",
+            "affinity": "INTEGER",
+            "notNull": false
+          },
+          {
+            "fieldPath": "type",
+            "columnName": "type",
+            "affinity": "TEXT",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "columnNames": [
+            "id"
+          ],
+          "autoGenerate": false
+        },
+        "indices": [],
+        "foreignKeys": []
+      },
+      {
+        "tableName": "Category",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER, `name` TEXT NOT NULL, `amount` REAL NOT NULL, `repeat` TEXT, `color` INTEGER NOT NULL, PRIMARY KEY(`id`))",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": false
+          },
+          {
+            "fieldPath": "name",
+            "columnName": "name",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "amount",
+            "columnName": "amount",
+            "affinity": "REAL",
+            "notNull": true
+          },
+          {
+            "fieldPath": "repeat",
+            "columnName": "repeat",
+            "affinity": "TEXT",
+            "notNull": false
+          },
+          {
+            "fieldPath": "color",
+            "columnName": "color",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "columnNames": [
+            "id"
+          ],
+          "autoGenerate": false
+        },
+        "indices": [],
+        "foreignKeys": []
+      }
+    ],
+    "setupQueries": [
+      "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)",
+      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, \"b68fd456557e5153b2fe6514a5193c07\")"
+    ]
+  }
+}

app/src/main/AndroidManifest.xml

@@ -20,7 +20,8 @@
                 android:name="android.app.shortcuts"
                 android:resource="@xml/shortcuts" />
         </activity>
-        <activity android:name="com.wbrawner.budget.addedittransaction.AddEditTransactionActivity" />
+        <activity android:name="com.wbrawner.budget.transactions.AddEditTransactionActivity" />
+        <activity android:name="com.wbrawner.budget.categories.AddEditCategoryActivity" />
     </application>
 
 </manifest>

app/src/main/java/com/wbrawner/budget/AllowanceApplication.kt

@@ -3,9 +3,10 @@ package com.wbrawner.budget
 import android.app.Application
 import android.arch.persistence.room.Room
 import android.content.Context
-import com.wbrawner.budget.data.TransactionDao
+import com.wbrawner.budget.data.dao.TransactionDao
-import com.wbrawner.budget.data.TransactionsDatabase
+import com.wbrawner.budget.data.BudgetDatabase
-import com.wbrawner.budget.BuildConfig
+import com.wbrawner.budget.data.dao.CategoryDao
+import com.wbrawner.budget.data.migrations.MIGRATION_1_2
 import org.acra.ACRA
 import org.acra.annotation.AcraCore
 import org.acra.annotation.AcraHttpSender
@@ -18,23 +19,28 @@ import org.acra.sender.HttpSender
         basicAuthPassword = BuildConfig.ACRA_PASS,
         httpMethod = HttpSender.Method.POST)
 class AllowanceApplication: Application() {
-    lateinit var database: TransactionsDatabase
+    lateinit var database: BudgetDatabase
     private set
 
-    lateinit var dao: TransactionDao
+    lateinit var transactionDao: TransactionDao
+    private set
+
+    lateinit var categoryDao: CategoryDao
     private set
 
     override fun onCreate() {
         super.onCreate()
 
-        database = Room.databaseBuilder(applicationContext, TransactionsDatabase::class.java, "transactions")
+        database = Room.databaseBuilder(applicationContext, BudgetDatabase::class.java, "transactions")
+                .addMigrations(MIGRATION_1_2())
                 .build()
-        dao = database.dao()
+        transactionDao = database.transactionDao()
+        categoryDao = database.categoryDao()
     }
 
 
     override fun attachBaseContext(base: Context?) {
         super.attachBaseContext(base)
-        ACRA.init(this)
+        if (!BuildConfig.DEBUG) ACRA.init(this)
     }
-}
+}

app/src/main/java/com/wbrawner/budget/categories/AddEditCategoryActivity.kt

@@ -0,0 +1,96 @@
+package com.wbrawner.budget.categories
+
+import android.arch.lifecycle.Observer
+import android.arch.lifecycle.ViewModelProviders
+import android.graphics.Color
+import android.os.Bundle
+import android.support.v7.app.AppCompatActivity
+import android.view.Menu
+import android.view.MenuItem
+import com.wbrawner.budget.R
+import com.wbrawner.budget.data.model.Category
+import kotlinx.android.synthetic.main.activity_add_edit_category.*
+
+class AddEditCategoryActivity : AppCompatActivity() {
+    lateinit var viewModel: CategoryViewModel
+    var id: Int? = null
+    var menu: Menu? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_add_edit_category)
+        setSupportActionBar(action_bar)
+        supportActionBar?.setDisplayHomeAsUpEnabled(true)
+        viewModel = ViewModelProviders.of(this).get(CategoryViewModel::class.java)
+
+        if (intent?.hasExtra(EXTRA_CATEGORY_ID) == false) {
+            setTitle(R.string.title_add_category)
+            return
+        }
+
+        viewModel.getCategory(intent!!.extras!!.getInt(EXTRA_CATEGORY_ID))
+                .observe(this, Observer<Category> { category ->
+                    if (category == null) {
+                        menu?.findItem(R.id.action_delete)?.isVisible = false
+                        return@Observer
+                    }
+                    id = category.id
+                    setTitle(R.string.title_edit_category)
+                    menu?.findItem(R.id.action_delete)?.isVisible = true
+                    edit_category_name.setText(category.name)
+                    edit_category_amount.setText(String.format("%.02f", category.amount))
+                })
+    }
+
+
+    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
+        menuInflater.inflate(R.menu.menu_add_edit, menu)
+        if (id != null) {
+            menu?.findItem(R.id.action_delete)?.isVisible = true
+        }
+        return true
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem?): Boolean {
+        when (item?.itemId) {
+            android.R.id.home -> onBackPressed()
+            R.id.action_save -> {
+                if (!validateFields()) return true
+                viewModel.saveCategory(Category(
+                        id = id,
+                        name = edit_category_name.text.toString(),
+                        amount = edit_category_amount.text.toString().toDouble(),
+                        color = Color.parseColor("#FF0000"),
+                        repeat = "never"
+                ))
+                finish()
+            }
+            R.id.action_delete -> {
+                viewModel.deleteCategoryById(this@AddEditCategoryActivity.id!!)
+                finish()
+            }
+        }
+        return true
+    }
+
+
+    private fun validateFields(): Boolean {
+        var errors = false
+        if (edit_category_name.text.isEmpty()) {
+            edit_category_name.error = getString(R.string.required_field_name)
+            errors = true
+        }
+
+        if (edit_category_amount.text.isEmpty()) {
+            edit_category_amount.error = getString(R.string.required_field_amount)
+            errors = true
+        }
+
+        return !errors
+    }
+
+
+    companion object {
+        const val EXTRA_CATEGORY_ID = "EXTRA_CATEGORY_ID"
+    }
+}

app/src/main/java/com/wbrawner/budget/categories/CategoryAdapter.kt

@@ -0,0 +1,64 @@
+package com.wbrawner.budget.categories
+
+import android.arch.lifecycle.LifecycleOwner
+import android.arch.lifecycle.Observer
+import android.content.Intent
+import android.support.v4.content.ContextCompat.startActivity
+import android.support.v7.widget.RecyclerView
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.ProgressBar
+import android.widget.TextView
+import com.wbrawner.budget.R
+import com.wbrawner.budget.categories.AddEditCategoryActivity.Companion.EXTRA_CATEGORY_ID
+import com.wbrawner.budget.data.model.Category
+
+class CategoryAdapter(
+        private val lifecycleOwner: LifecycleOwner,
+        private val data: List<Category>,
+        private val viewModel: CategoryViewModel
+) : RecyclerView.Adapter<CategoryAdapter.ViewHolder>() {
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
+        val view = LayoutInflater.from(parent.context)
+                .inflate(R.layout.list_item_category, parent, false)
+        return ViewHolder(view)
+    }
+
+    override fun getItemCount(): Int = data.size
+
+    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
+        val category = data[position]
+        holder.title?.text = category.name
+        holder.amount?.text = String.format("${'$'}%.02f", category.amount)
+        viewModel.getCurrentBalance(category.id!!)
+                .observe(lifecycleOwner, Observer<Double> { balance ->
+                    holder.progress?.isIndeterminate = false
+                    if (balance == null) {
+                        holder.progress?.progress = 0
+                    } else {
+                        holder.progress?.max = category.amount.toInt()
+                        holder.progress?.setProgress(
+                                Math.abs(balance).toInt(),
+                                true
+                        )
+                    }
+                })
+        holder.itemView.setOnClickListener {
+            startActivity(
+                    it.context.applicationContext,
+                    Intent(it.context.applicationContext, AddEditCategoryActivity::class.java)
+                            .apply {
+                                putExtra(EXTRA_CATEGORY_ID, category.id)
+                            },
+                    null
+            )
+        }
+    }
+
+    inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
+        val title: TextView? = itemView.findViewById(R.id.category_title)
+        val amount: TextView? = itemView.findViewById(R.id.category_amount)
+        val progress: ProgressBar? = itemView.findViewById(R.id.category_progress)
+    }
+}

app/src/main/java/com/wbrawner/budget/categories/CategoryListFragment.kt

@@ -0,0 +1,69 @@
+package com.wbrawner.budget.categories
+
+import android.arch.lifecycle.Observer
+import android.arch.lifecycle.ViewModelProviders
+import android.content.Intent
+import android.os.Bundle
+import android.support.design.widget.FloatingActionButton
+import android.support.text.emoji.widget.EmojiTextView
+import android.support.v4.app.Fragment
+import android.support.v7.widget.LinearLayoutManager
+import android.support.v7.widget.RecyclerView
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import com.wbrawner.budget.R
+import com.wbrawner.budget.data.model.Category
+
+class CategoryListFragment : Fragment() {
+    lateinit var viewModel: CategoryViewModel
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        if (activity == null) {
+            return
+        }
+
+        if (savedInstanceState != null) {
+            return
+        }
+
+        viewModel = ViewModelProviders.of(activity!!).get(CategoryViewModel::class.java)
+    }
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+        val view = inflater.inflate(R.layout.fragment_transaction_list, container, false)
+        val recyclerView = view.findViewById<RecyclerView>(R.id.list_transactions)
+        val fab = view.findViewById<FloatingActionButton>(R.id.fab_add_transaction)
+        recyclerView.layoutManager = LinearLayoutManager(activity)
+        viewModel.getCategories()
+                .observe(this, Observer<List<Category>> { data ->
+                    val noDataView = view.findViewById<EmojiTextView>(R.id.transaction_list_no_data)
+                    if (data == null || data.isEmpty()) {
+                        recyclerView.adapter = null
+                        noDataView?.setText("No data FIX ME")
+                        recyclerView?.visibility = View.GONE
+                        noDataView?.visibility = View.VISIBLE
+                    } else {
+                        recyclerView.adapter = CategoryAdapter(this, data, viewModel)
+                        recyclerView.visibility = View.VISIBLE
+                        noDataView.visibility = View.GONE
+                    }
+                })
+        recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
+            override fun onScrolled(recyclerView: RecyclerView?, dx: Int, dy: Int) {
+                if (dy > 0) fab.hide() else fab.show()
+            }
+        })
+        fab.setOnClickListener {
+            startActivity(Intent(activity, AddEditCategoryActivity::class.java))
+        }
+
+        return view
+    }
+
+    companion object {
+        const val TAG_FRAGMENT = "categories"
+        const val TITLE_FRAGMENT = R.string.title_categories
+    }
+}

app/src/main/java/com/wbrawner/budget/categories/CategoryViewModel.kt

@@ -0,0 +1,26 @@
+package com.wbrawner.budget.categories
+
+import android.app.Application
+import android.arch.lifecycle.AndroidViewModel
+import android.arch.lifecycle.LiveData
+import com.wbrawner.budget.AllowanceApplication
+import com.wbrawner.budget.data.model.Category
+import com.wbrawner.budget.data.CategoryRepository
+
+class CategoryViewModel(application: Application): AndroidViewModel(application) {
+    private val categoryRepo = CategoryRepository((application as AllowanceApplication).categoryDao)
+
+    fun getCategory(id: Int): LiveData<Category> = categoryRepo.getCategory(id)
+
+    fun getCategories(): LiveData<List<Category>> = categoryRepo.getCategories()
+
+    fun saveCategory(category: Category) = categoryRepo.save(category)
+
+    fun deleteCategory(category: Category) = categoryRepo.delete(category)
+
+    fun deleteCategoryById(id: Int) = categoryRepo.deleteById(id)
+
+    fun getCurrentBalance(id: Int) = categoryRepo.getCurrentBalance(id)
+
+    fun getTransactions(id: Int) = categoryRepo.getTransactions(id)
+}

app/src/main/java/com/wbrawner/budget/data/BudgetDatabase.kt

@@ -0,0 +1,16 @@
+package com.wbrawner.budget.data
+
+import android.arch.persistence.room.Database
+import android.arch.persistence.room.RoomDatabase
+import android.arch.persistence.room.TypeConverters
+import com.wbrawner.budget.data.dao.CategoryDao
+import com.wbrawner.budget.data.dao.TransactionDao
+import com.wbrawner.budget.data.model.Category
+import com.wbrawner.budget.data.model.Transaction
+
+@Database(entities = [(Transaction::class), (Category::class)], version = 2)
+@TypeConverters(DateTypeConverter::class, TransactionTypeTypeConverter::class)
+abstract class BudgetDatabase: RoomDatabase() {
+    abstract fun transactionDao(): TransactionDao
+    abstract fun categoryDao(): CategoryDao
+}

app/src/main/java/com/wbrawner/budget/data/CategoryRepository.kt

@@ -0,0 +1,44 @@
+package com.wbrawner.budget.data
+
+import android.arch.lifecycle.LiveData
+import android.os.Handler
+import android.os.HandlerThread
+import com.wbrawner.budget.data.dao.CategoryDao
+import com.wbrawner.budget.data.model.Category
+import com.wbrawner.budget.data.model.Transaction
+
+class CategoryRepository(private val dao: CategoryDao) {
+    private val handler: Handler
+
+    init {
+        val thread = HandlerThread("category")
+        thread.start()
+        handler = Handler(thread.looper)
+    }
+
+    fun getCategories(): LiveData<List<Category>> = dao.loadMultiple()
+
+
+    fun getCategory(id: Int): LiveData<Category> = dao.load(id)
+
+
+    fun save(category: Category) {
+        handler.post { dao.save(category) }
+    }
+
+
+    fun delete(category: Category) {
+        handler.post { dao.delete(category) }
+    }
+
+
+    fun deleteById(id: Int) {
+        handler.post { dao.deleteById(id) }
+    }
+
+
+    fun getCurrentBalance(id: Int): LiveData<Double> = dao.getBalanceForCategory(id)
+
+
+    fun getTransactions(id: Int): LiveData<List<Transaction>> = dao.getTransactions(id)
+}

app/src/main/java/com/wbrawner/budget/data/TransactionRepository.kt

@@ -3,10 +3,13 @@ package com.wbrawner.budget.data
 import android.arch.lifecycle.LiveData
 import android.os.Handler
 import android.os.HandlerThread
+import com.wbrawner.budget.data.dao.TransactionDao
+import com.wbrawner.budget.data.model.Transaction
+import com.wbrawner.budget.data.model.TransactionCategory
+import com.wbrawner.budget.data.model.TransactionWithCategory
 
-class TransactionRepository(val dao: TransactionDao) {
+class TransactionRepository(private val dao: TransactionDao) {
-    val handler: Handler
+    private val handler: Handler
-    val uiHandler: Handler = Handler()
 
     init {
         val thread = HandlerThread("transactions")
@@ -14,36 +17,13 @@ class TransactionRepository(val dao: TransactionDao) {
         handler = Handler(thread.looper)
     }
 
-    fun getTransactionsByType(count: Int, type: TransactionType): LiveData<List<Transaction>> =
+    fun getTransactionsByType(count: Int, type: TransactionType): LiveData<List<TransactionWithCategory>> =
             dao.loadMultipleByType(count, type)
 
-    fun getTransactions(count: Int): LiveData<List<Transaction>> = dao.loadMultiple(count)
+    fun getTransactions(count: Int): LiveData<List<TransactionWithCategory>> = dao.loadMultiple(count)
 
-//    fun getTransactions(count: Int): LiveData<List<Transaction>> {
-//        val data = MutableLiveData<List<Transaction>>()
-//
-//        handler.post {
-//            val transactions = ArrayList<Transaction>()
-//            for (i in 0..count) {
-//                transactions.add(Transaction(
-//                        i,
-//                        "Transaction $i",
-//                        Date(),
-//                        "Spent some money on something",
-//                        (Math.random() * 100).toFloat(),
-//                        TransactionType.EXPENSE
-//                ))
-//            }
-//
-//            uiHandler.post {
-//                data.value = transactions
-//            }
-//        }
-//
-//        return data
-//    }
 
-    fun getTransaction(id: Int): LiveData<Transaction> = dao.load(id)
+    fun getTransaction(id: Int): LiveData<TransactionWithCategory> = dao.load(id)
 
 
     fun save(transaction: Transaction) {
@@ -62,4 +42,6 @@ class TransactionRepository(val dao: TransactionDao) {
 
 
     fun getCurrentBalance(): LiveData<Double> = dao.getBalance()
+
+    fun getCategories(): LiveData<List<TransactionCategory>> = dao.loadCategories()
 }

app/src/main/java/com/wbrawner/budget/data/TransactionsDatabase.kt

@@ -1,11 +0,0 @@
-package com.wbrawner.budget.data
-
-import android.arch.persistence.room.Database
-import android.arch.persistence.room.RoomDatabase
-import android.arch.persistence.room.TypeConverters
-
-@Database(entities = [(Transaction::class)], version = 1, exportSchema = false)
-@TypeConverters(DateTypeConverter::class, TransactionTypeTypeConverter::class)
-abstract class TransactionsDatabase: RoomDatabase() {
-    abstract fun dao(): TransactionDao
-}

app/src/main/java/com/wbrawner/budget/data/TypeConverters.kt

@@ -1,5 +1,6 @@
 package com.wbrawner.budget.data
 
+import android.arch.persistence.room.TypeConverter
 import java.text.SimpleDateFormat
 import java.util.*
 

app/src/main/java/com/wbrawner/budget/data/dao/CategoryDao.kt

@@ -0,0 +1,37 @@
+package com.wbrawner.budget.data.dao
+
+import android.arch.lifecycle.LiveData
+import android.arch.persistence.room.Dao
+import android.arch.persistence.room.Delete
+import android.arch.persistence.room.Insert
+import android.arch.persistence.room.OnConflictStrategy.REPLACE
+import android.arch.persistence.room.Query
+import com.wbrawner.budget.data.model.Category
+import com.wbrawner.budget.data.model.Transaction
+
+@Dao
+interface CategoryDao {
+    @Insert(onConflict = REPLACE)
+    fun save(category: Category)
+
+    @Query("SELECT * FROM `Category` WHERE id = :id")
+    fun load(id: Int): LiveData<Category>
+
+    @Query("SELECT * FROM `Category`")
+    fun loadMultiple(): LiveData<List<Category>>
+
+    @Query("SELECT " +
+            "(SELECT TOTAL(amount) from `Transaction` WHERE type = 'INCOME' AND categoryId = :categoryId) " +
+            "- (SELECT TOTAL(amount) from `Transaction` WHERE type = 'EXPENSE' AND categoryId = :categoryId)")
+    fun getBalanceForCategory(categoryId: Int): LiveData<Double>
+
+    @Delete
+    fun delete(category: Category)
+
+    @Query("DELETE FROM `Category` WHERE id = :id")
+    fun deleteById(id: Int)
+
+
+    @Query("SELECT * FROM `Transaction` WHERE categoryId = :id")
+    fun getTransactions(id: Int): LiveData<List<Transaction>>
+}

app/src/main/java/com/wbrawner/budget/data/dao/TransactionDao.kt

@@ -1,4 +1,4 @@
-package com.wbrawner.budget.data
+package com.wbrawner.budget.data.dao
 
 import android.arch.lifecycle.LiveData
 import android.arch.persistence.room.Dao
@@ -6,6 +6,10 @@ import android.arch.persistence.room.Delete
 import android.arch.persistence.room.Insert
 import android.arch.persistence.room.OnConflictStrategy.REPLACE
 import android.arch.persistence.room.Query
+import com.wbrawner.budget.data.model.Transaction
+import com.wbrawner.budget.data.model.TransactionCategory
+import com.wbrawner.budget.data.TransactionType
+import com.wbrawner.budget.data.model.TransactionWithCategory
 
 @Dao
 interface TransactionDao {
@@ -13,13 +17,13 @@ interface TransactionDao {
     fun save(transaction: Transaction)
 
     @Query("SELECT * FROM `Transaction` WHERE id = :id")
-    fun load(id: Int): LiveData<Transaction>
+    fun load(id: Int): LiveData<TransactionWithCategory>
 
     @Query("SELECT * FROM `Transaction` LIMIT :count")
-    fun loadMultiple(count: Int): LiveData<List<Transaction>>
+    fun loadMultiple(count: Int): LiveData<List<TransactionWithCategory>>
 
     @Query("SELECT * FROM `Transaction` WHERE type = :type LIMIT :count")
-    fun loadMultipleByType(count: Int, type: TransactionType): LiveData<List<Transaction>>
+    fun loadMultipleByType(count: Int, type: TransactionType): LiveData<List<TransactionWithCategory>>
 
     @Query("SELECT (SELECT TOTAL(amount) from `Transaction` WHERE type = 'INCOME') - (SELECT TOTAL(amount) from `Transaction` WHERE type = 'EXPENSE')")
     fun getBalance(): LiveData<Double>
@@ -29,4 +33,7 @@ interface TransactionDao {
 
     @Query("DELETE FROM `Transaction` WHERE id = :id")
     fun deleteById(id: Int)
+
+    @Query("SELECT id,name from `Category`")
+    fun loadCategories(): LiveData<List<TransactionCategory>>
 }

app/src/main/java/com/wbrawner/budget/data/migrations/MIGRATION_1_2.kt

@@ -0,0 +1,13 @@
+package com.wbrawner.budget.data.migrations
+
+import android.arch.persistence.db.SupportSQLiteDatabase
+import android.arch.persistence.room.migration.Migration
+
+class MIGRATION_1_2: Migration(1, 2) {
+    override fun migrate(database: SupportSQLiteDatabase) {
+        database.execSQL("CREATE TABLE `Category` (`id` INTEGER, `name` TEXT, `amount` REAL, " +
+                "`repeat` TEXT, `color` INTEGER PRIMARY KEY (`id`))")
+        database.execSQL("ALTER TABLE `Transaction` ADD COLUMN categoryId")
+    }
+
+}

app/src/main/java/com/wbrawner/budget/data/model/Category.kt

@@ -0,0 +1,15 @@
+package com.wbrawner.budget.data.model
+
+import android.arch.persistence.room.Entity
+import android.arch.persistence.room.PrimaryKey
+import android.support.annotation.ColorInt
+
+@Entity
+class Category(
+        @PrimaryKey
+        val id: Int?,
+        val name: String,
+        val amount: Double,
+        val repeat: String?,
+        @ColorInt val color: Int
+)

app/src/main/java/com/wbrawner/budget/data/model/Transaction.kt

@@ -1,7 +1,8 @@
-package com.wbrawner.budget.data
+package com.wbrawner.budget.data.model
 
 import android.arch.persistence.room.Entity
 import android.arch.persistence.room.PrimaryKey
+import com.wbrawner.budget.data.TransactionType
 import java.util.*
 
 @Entity
@@ -12,5 +13,6 @@ class Transaction(
         val date: Date,
         val description: String,
         val amount: Double,
+        val categoryId: Int?,
         val type: TransactionType
 )

app/src/main/java/com/wbrawner/budget/data/model/TransactionCategory.kt

@@ -0,0 +1,10 @@
+package com.wbrawner.budget.data.model
+
+class TransactionCategory(
+    val id: Int,
+    val name: String
+) {
+    override fun toString(): String {
+        return name
+    }
+}

app/src/main/java/com/wbrawner/budget/data/model/TransactionWithCategory.kt

@@ -0,0 +1,14 @@
+package com.wbrawner.budget.data.model
+
+import android.arch.persistence.room.Embedded
+import android.arch.persistence.room.Relation
+import com.wbrawner.budget.data.model.Category
+import com.wbrawner.budget.data.model.Transaction
+
+class TransactionWithCategory {
+        @Embedded
+        lateinit var transaction: Transaction
+
+        @Relation(parentColumn = "id", entityColumn = "id")
+        lateinit var categorySet: Set<Category>
+}

app/src/main/java/com/wbrawner/budget/overview/OverviewFragment.kt

@@ -20,12 +20,7 @@ class OverviewFragment : Fragment() {
             return
         }
 
-        if (savedInstanceState != null) {
-            return
-        }
-
         viewModel = ViewModelProviders.of(activity!!).get(TransactionViewModel::class.java)
-
     }
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
@@ -64,4 +59,4 @@ class OverviewFragment : Fragment() {
         const val TAG_FRAGMENT = "overview"
         const val TITLE_FRAGMENT = R.string.app_name
     }
-}
+}

app/src/main/java/com/wbrawner/budget/transactions/AddEditTransactionActivity.kt

@@ -1,4 +1,4 @@
-package com.wbrawner.budget.addedittransaction
+package com.wbrawner.budget.transactions
 
 import android.arch.lifecycle.Observer
 import android.arch.lifecycle.ViewModelProviders
@@ -6,10 +6,12 @@ import android.os.Bundle
 import android.support.v7.app.AppCompatActivity
 import android.view.Menu
 import android.view.MenuItem
+import android.widget.ArrayAdapter
 import com.wbrawner.budget.R
-import com.wbrawner.budget.data.Transaction
+import com.wbrawner.budget.data.model.Transaction
+import com.wbrawner.budget.data.model.TransactionCategory
 import com.wbrawner.budget.data.TransactionType
-import com.wbrawner.budget.transactions.TransactionViewModel
+import com.wbrawner.budget.data.model.TransactionWithCategory
 import kotlinx.android.synthetic.main.activity_add_edit_transaction.*
 import java.util.*
 
@@ -26,6 +28,22 @@ class AddEditTransactionActivity : AppCompatActivity() {
         setSupportActionBar(action_bar)
         supportActionBar?.setDisplayHomeAsUpEnabled(true)
         viewModel = ViewModelProviders.of(this).get(TransactionViewModel::class.java)
+        viewModel.getCategories()
+                .observe(this, Observer<List<TransactionCategory>> { categories ->
+                    val adapter = ArrayAdapter<TransactionCategory>(
+                            this@AddEditTransactionActivity,
+                            android.R.layout.simple_list_item_1
+                    )
+
+                    adapter.add(TransactionCategory(0, getString(R.string.uncategorized)))
+                    if (categories == null || categories.isEmpty()) {
+                        return@Observer
+                    }
+
+                    adapter.addAll(categories)
+                    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
+                    edit_transaction_category.adapter = adapter
+                })
         if (intent?.hasExtra(EXTRA_TYPE) == true) {
             type = TransactionType.valueOf(intent?.extras?.getString(EXTRA_TYPE, "EXPENSE")
                     ?: "EXPENSE")
@@ -37,11 +55,12 @@ class AddEditTransactionActivity : AppCompatActivity() {
         }
 
         viewModel.getTransaction(intent!!.extras!!.getInt(EXTRA_TRANSACTION_ID))
-                .observe(this, Observer<Transaction> { transaction ->
+                .observe(this, Observer<TransactionWithCategory> { transactionWithCategory ->
-                    if (transaction == null) {
+                    if (transactionWithCategory == null) {
                         menu?.findItem(R.id.action_delete)?.isVisible = false
                         return@Observer
                     }
+                    val transaction = transactionWithCategory.transaction
                     id = transaction.id
                     type = transaction.type
                     setTitle(type.editTitle)
@@ -55,6 +74,15 @@ class AddEditTransactionActivity : AppCompatActivity() {
                     val month = field.get(Calendar.MONTH)
                     val day = field.get(Calendar.DAY_OF_MONTH)
                     edit_transaction_date.updateDate(year, month, day)
+                    if (transactionWithCategory.categorySet.isNotEmpty()) {
+                        val category = transactionWithCategory.categorySet.first()
+                        for (i in 0 until edit_transaction_category.adapter.count) {
+                            if (category.id == (edit_transaction_category.adapter.getItem(i) as TransactionCategory).id) {
+                                edit_transaction_category.setSelection(i)
+                                break
+                            }
+                        }
+                    }
                 })
     }
 
@@ -81,7 +109,8 @@ class AddEditTransactionActivity : AppCompatActivity() {
                         date = cal.time,
                         description = edit_transaction_description.text.toString(),
                         amount = edit_transaction_amount.text.toString().toDouble(),
-                        type = type
+                        type = type,
+                        categoryId = (edit_transaction_category.selectedItem as TransactionCategory).id
                 ))
                 finish()
             }

app/src/main/java/com/wbrawner/budget/transactions/TransactionAdapter.kt

@@ -8,13 +8,15 @@ import android.view.View
 import android.view.ViewGroup
 import android.widget.TextView
 import com.wbrawner.budget.R
-import com.wbrawner.budget.addedittransaction.AddEditTransactionActivity
+import com.wbrawner.budget.transactions.AddEditTransactionActivity.Companion.EXTRA_TRANSACTION_ID
-import com.wbrawner.budget.addedittransaction.AddEditTransactionActivity.Companion.EXTRA_TRANSACTION_ID
+import com.wbrawner.budget.data.model.Transaction
-import com.wbrawner.budget.data.Transaction
+import com.wbrawner.budget.data.model.TransactionWithCategory
 import java.text.SimpleDateFormat
 
-class TransactionAdapter(private val data: List<Transaction>)
+class TransactionAdapter() : RecyclerView.Adapter<TransactionAdapter.ViewHolder>() {
-    : RecyclerView.Adapter<TransactionAdapter.ViewHolder>() {
+    private lateinit var data: List<Any>
+    private lateinit var listType: Class<Any>
+
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
         val view = LayoutInflater.from(parent.context)
                 .inflate(R.layout.list_item_transaction, parent, false)
@@ -24,7 +26,9 @@ class TransactionAdapter(private val data: List<Transaction>)
     override fun getItemCount(): Int = data.size
 
     override fun onBindViewHolder(holder: ViewHolder, position: Int) {
-        val transaction = data[position]
+        val transaction: Transaction =
+                if (listType == TransactionWithCategory::class.java) (data[position] as TransactionWithCategory).transaction
+                else data[position] as Transaction
         holder.title.text = transaction.title
         holder.date.text = SimpleDateFormat.getDateInstance(SimpleDateFormat.SHORT).format(transaction.date)
         holder.amount.text = String.format("${'$'}%.02f", transaction.amount)
@@ -44,7 +48,16 @@ class TransactionAdapter(private val data: List<Transaction>)
         }
     }
 
-    inner class ViewHolder(itemView: View): RecyclerView.ViewHolder(itemView) {
+    constructor(transactions: List<Any>) : this() {
+        if (transactions.isEmpty()) {
+            return
+        }
+
+        listType = transactions.first().javaClass
+        data = transactions
+    }
+
+    inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
         val title = itemView.findViewById<TextView>(R.id.transaction_title)
         val date = itemView.findViewById<TextView>(R.id.transaction_date)
         val amount = itemView.findViewById<TextView>(R.id.transaction_amount)

app/src/main/java/com/wbrawner/budget/transactions/TransactionListActivity.kt

@@ -6,6 +6,7 @@ import android.support.text.emoji.EmojiCompat
 import android.support.text.emoji.bundled.BundledEmojiCompatConfig
 import android.support.v7.app.AppCompatActivity
 import com.wbrawner.budget.R
+import com.wbrawner.budget.categories.CategoryListFragment
 import com.wbrawner.budget.data.TransactionType
 import com.wbrawner.budget.overview.OverviewFragment
 import kotlinx.android.synthetic.main.activity_transaction_list.*
@@ -21,6 +22,7 @@ class TransactionListActivity : AppCompatActivity() {
             when (item.itemId) {
                 R.id.action_expenses -> updateFragment(TransactionType.EXPENSE)
                 R.id.action_income -> updateFragment(TransactionType.INCOME)
+                R.id.action_categories -> updateFragment(CategoryListFragment.TAG_FRAGMENT, CategoryListFragment.TITLE_FRAGMENT)
                 else ->
                     updateFragment(OverviewFragment.TAG_FRAGMENT, OverviewFragment.TITLE_FRAGMENT)
             }
@@ -38,13 +40,17 @@ class TransactionListActivity : AppCompatActivity() {
         var fragment = supportFragmentManager.findFragmentByTag(tag)
         val ft = supportFragmentManager.beginTransaction()
         if (fragment == null) {
-            fragment = if (tag == "overview") OverviewFragment()
+            fragment = when (tag) {
-            else
+                OverviewFragment.TAG_FRAGMENT -> OverviewFragment()
-                TransactionListFragment().apply {
+                CategoryListFragment.TAG_FRAGMENT -> CategoryListFragment()
-                    arguments = Bundle().apply {
+                else -> {
-                        putSerializable(TransactionListFragment.ARG_TYPE, TransactionType.valueOf(tag))
+                    TransactionListFragment().apply {
+                        arguments = Bundle().apply {
+                            putSerializable(TransactionListFragment.ARG_TYPE, TransactionType.valueOf(tag))
+                        }
                     }
                 }
+            }
             ft.add(R.id.content_container, fragment, tag)
         }
         for (fmFragment in supportFragmentManager.fragments) {

app/src/main/java/com/wbrawner/budget/transactions/TransactionListFragment.kt

@@ -13,10 +13,9 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import com.wbrawner.budget.R
-import com.wbrawner.budget.addedittransaction.AddEditTransactionActivity
+import com.wbrawner.budget.transactions.AddEditTransactionActivity.Companion.EXTRA_TYPE
-import com.wbrawner.budget.addedittransaction.AddEditTransactionActivity.Companion.EXTRA_TYPE
-import com.wbrawner.budget.data.Transaction
 import com.wbrawner.budget.data.TransactionType
+import com.wbrawner.budget.data.model.TransactionWithCategory
 
 class TransactionListFragment : Fragment() {
     lateinit var viewModel: TransactionViewModel
@@ -43,7 +42,7 @@ class TransactionListFragment : Fragment() {
         val fab = view.findViewById<FloatingActionButton>(R.id.fab_add_transaction)
         recyclerView.layoutManager = LinearLayoutManager(activity)
         viewModel.getTransactionsByType(20, type)
-                .observe(this, Observer<List<Transaction>> { data ->
+                .observe(this, Observer<List<TransactionWithCategory>> { data ->
                     val noDataView = view.findViewById<EmojiTextView>(R.id.transaction_list_no_data)
                     if (data == null || data.isEmpty()) {
                         recyclerView.adapter = null

app/src/main/java/com/wbrawner/budget/transactions/TransactionViewModel.kt

@@ -4,22 +4,25 @@ import android.app.Application
 import android.arch.lifecycle.AndroidViewModel
 import android.arch.lifecycle.LiveData
 import com.wbrawner.budget.AllowanceApplication
-import com.wbrawner.budget.data.Transaction
+import com.wbrawner.budget.data.*
-import com.wbrawner.budget.data.TransactionRepository
+import com.wbrawner.budget.data.model.Transaction
-import com.wbrawner.budget.data.TransactionType
+import com.wbrawner.budget.data.model.TransactionCategory
+import com.wbrawner.budget.data.model.TransactionWithCategory
 
 class TransactionViewModel(application: Application): AndroidViewModel(application) {
-    private val transactionRepo = TransactionRepository((application as AllowanceApplication).dao)
+    private val transactionRepo = TransactionRepository((application as AllowanceApplication).transactionDao)
 
-    fun getTransaction(id: Int): LiveData<Transaction> = transactionRepo.getTransaction(id)
+    fun getTransaction(id: Int): LiveData<TransactionWithCategory> = transactionRepo.getTransaction(id)
 
-    fun getTransactions(count: Int): LiveData<List<Transaction>> = transactionRepo.getTransactions(count)
+    fun getTransactions(count: Int): LiveData<List<TransactionWithCategory>> = transactionRepo.getTransactions(count)
 
-    fun getTransactionsByType(count: Int, type: TransactionType): LiveData<List<Transaction>>
+    fun getTransactionsByType(count: Int, type: TransactionType): LiveData<List<TransactionWithCategory>>
             = transactionRepo.getTransactionsByType(count, type)
 
     fun getCurrentBalance(): LiveData<Double> = transactionRepo.getCurrentBalance()
 
+    fun getCategories(): LiveData<List<TransactionCategory>> = transactionRepo.getCategories()
+
     fun saveTransaction(transaction: Transaction) = transactionRepo.save(transaction)
 
     fun deleteTransaction(transaction: Transaction) = transactionRepo.delete(transaction)

app/src/main/res/drawable/ic_baseline_category_24px.xml

@@ -0,0 +1,15 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+  <path
+      android:fillColor="#FF000000"
+      android:pathData="M12,2l-5.5,9h11z"/>
+  <path
+      android:fillColor="#FF000000"
+      android:pathData="M17.5,17.5m-4.5,0a4.5,4.5 0,1 1,9 0a4.5,4.5 0,1 1,-9 0"/>
+  <path
+      android:fillColor="#FF000000"
+      android:pathData="M3,13.5h8v8H3z"/>
+</vector>

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

@@ -0,0 +1,81 @@
+<?xml version="1.0" encoding="utf-8"?>
+<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <android.support.v7.widget.Toolbar
+        android:id="@+id/action_bar"
+        android:layout_width="match_parent"
+        android:layout_height="?attr/actionBarSize"
+        android:elevation="4dp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <ScrollView
+        android:id="@+id/scrollView2"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/action_bar">
+
+        <android.support.constraint.ConstraintLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:padding="16dp">
+
+            <android.support.design.widget.TextInputLayout
+                android:id="@+id/container_edit_category_name"
+                style="@style/AppTheme.EditText.Container"
+                android:hint="@string/prompt_category_name"
+                app:layout_constraintBottom_toTopOf="@+id/container_edit_category_amount"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toTopOf="parent">
+
+                <android.support.design.widget.TextInputEditText
+                    android:id="@+id/edit_category_name"
+                    style="@style/AppTheme.EditText"
+                    android:inputType="textCapWords" />
+            </android.support.design.widget.TextInputLayout>
+
+            <android.support.design.widget.TextInputLayout
+                android:id="@+id/container_edit_category_amount"
+                style="@style/AppTheme.EditText.Container"
+                android:hint="@string/prompt_category_amount"
+                app:layout_constraintBottom_toBottomOf="parent"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/container_edit_category_name">
+
+                <android.support.design.widget.TextInputEditText
+                    android:id="@+id/edit_category_amount"
+                    style="@style/AppTheme.EditText"
+                    android:inputType="numberDecimal" />
+            </android.support.design.widget.TextInputLayout>
+
+            <!--<TextView-->
+                <!--android:id="@+id/container_edit_transaction_date"-->
+                <!--style="@style/AppTheme.EditText.Hint"-->
+                <!--android:layout_width="match_parent"-->
+                <!--android:layout_height="wrap_content"-->
+                <!--android:layout_marginStart="4dp"-->
+                <!--android:text="@string/prompt_transaction_date"-->
+                <!--app:layout_constraintBottom_toTopOf="@+id/edit_transaction_date"-->
+                <!--app:layout_constraintEnd_toEndOf="parent"-->
+                <!--app:layout_constraintStart_toStartOf="parent"-->
+                <!--app:layout_constraintTop_toBottomOf="@+id/container_edit_transaction_amount" />-->
+
+            <!--<DatePicker-->
+                <!--android:id="@+id/edit_transaction_date"-->
+                <!--style="@style/AppTheme.DatePicker"-->
+                <!--app:layout_constraintBottom_toBottomOf="parent"-->
+                <!--app:layout_constraintEnd_toEndOf="parent"-->
+                <!--app:layout_constraintStart_toStartOf="parent"-->
+                <!--app:layout_constraintTop_toBottomOf="@+id/container_edit_transaction_date" />-->
+        </android.support.constraint.ConstraintLayout>
+    </ScrollView>
+</android.support.constraint.ConstraintLayout>

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

@@ -88,10 +88,31 @@
             <DatePicker
                 android:id="@+id/edit_transaction_date"
                 style="@style/AppTheme.DatePicker"
-                app:layout_constraintBottom_toBottomOf="parent"
+                app:layout_constraintBottom_toTopOf="@+id/container_edit_transaction_category"
                 app:layout_constraintEnd_toEndOf="parent"
                 app:layout_constraintStart_toStartOf="parent"
                 app:layout_constraintTop_toBottomOf="@+id/container_edit_transaction_date" />
+
+            <TextView
+                android:id="@+id/container_edit_transaction_category"
+                style="@style/AppTheme.EditText.Hint"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="4dp"
+                android:text="@string/prompt_transaction_category"
+                app:layout_constraintBottom_toTopOf="@+id/edit_transaction_category"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/edit_transaction_date" />
+
+            <Spinner
+                android:id="@+id/edit_transaction_category"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                app:layout_constraintBottom_toBottomOf="parent"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/container_edit_transaction_category" />
         </android.support.constraint.ConstraintLayout>
     </ScrollView>
 </android.support.constraint.ConstraintLayout>

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

@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="utf-8"?>
+<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:padding="16dp">
+
+    <TextView
+        android:id="@+id/category_title"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:textColor="@color/colorTextPrimary"
+        android:textSize="18sp"
+        app:layout_constraintBottom_toTopOf="@id/barrier"
+        app:layout_constraintEnd_toStartOf="@+id/category_amount"
+        app:layout_constraintHorizontal_chainStyle="spread_inside"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+
+    <TextView
+        android:id="@+id/category_amount"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:textSize="18sp"
+        app:layout_constraintHorizontal_chainStyle="spread_inside"
+        app:layout_constraintBottom_toTopOf="@id/barrier"
+        app:layout_constraintStart_toEndOf="@+id/category_title"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+
+    <android.support.constraint.Barrier
+        android:id="@+id/barrier"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        app:barrierDirection="bottom"
+        app:constraint_referenced_ids="category_title,category_amount" />
+
+    <ProgressBar
+        android:id="@+id/category_progress"
+        style="?android:attr/progressBarStyleHorizontal"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:indeterminate="true"
+        app:layout_constraintEnd_toStartOf="@+id/barrier"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/barrier" />
+</android.support.constraint.ConstraintLayout>

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

@@ -12,4 +12,8 @@
         android:id="@+id/action_income"
         android:icon="@drawable/ic_attach_money_black_24dp"
         android:title="@string/title_income" />
+    <item
+        android:id="@+id/action_categories"
+        android:icon="@drawable/ic_baseline_category_24px"
+        android:title="@string/title_categories" />
 </menu>

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

@@ -19,4 +19,13 @@
     <string name="title_edit_expense">Edit Expense</string>
     <string name="income_no_data">&#x1F333;\nGet to work! Money doesn\'t grow on trees after all</string>
     <string name="expenses_no_data">&#x1F914;\nAre you sure you haven\'t spent any money?</string>
+    <string name="title_categories">Categories</string>
+    <string name="title_edit_category">Edit Category</string>
+    <string name="prompt_category_amount">Amount</string>
+    <string name="prompt_category_name">Name</string>
+    <string name="title_add_category">Add Category</string>
+    <string name="uncategorized">Uncategorized</string>
+    <string name="prompt_transaction_category">Category</string>
+    <string name="required_field_name">Name is a required field</string>
+    <string name="required_field_amount">Amount is a required field</string>
 </resources>

app/src/main/res/xml/shortcuts.xml

@@ -10,7 +10,7 @@
         <intent
             android:action="android.intent.action.VIEW"
             android:targetPackage="com.wbrawner.budget"
-            android:targetClass="com.wbrawner.budget.addedittransaction.AddEditTransactionActivity">
+            android:targetClass="com.wbrawner.budget.transactions.AddEditTransactionActivity">
             <extra
                 android:name="EXTRA_TRANSACTION_TYPE"
                 android:value="EXPENSE" />
@@ -25,7 +25,7 @@
         <intent
             android:action="android.intent.action.VIEW"
             android:targetPackage="com.wbrawner.budget"
-            android:targetClass="com.wbrawner.budget.addedittransaction.AddEditTransactionActivity">
+            android:targetClass="com.wbrawner.budget.transactions.AddEditTransactionActivity">
             <extra
                 android:name="EXTRA_TRANSACTION_TYPE"
                 android:value="INCOME" />

build.gradle

@@ -1,13 +1,13 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.2.41'
+    ext.kotlin_version = '1.3.0'
     repositories {
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.1.4'
+        classpath 'com.android.tools.build:gradle:3.2.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
 
         // NOTE: Do not place your application dependencies here; they belong

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip