newer version

.idea/deploymentTargetSelector.xml

@@ -4,6 +4,14 @@
     <selectionStates>
       <SelectionState runConfigName="app">
         <option name="selectionMode" value="DROPDOWN" />
+        <DropdownSelection timestamp="2024-08-09T09:07:46.136113340Z">
+          <Target type="DEFAULT_BOOT">
+            <handle>
+              <DeviceId pluginId="LocalEmulator" identifier="path=/home/user/.android/avd/Pixel_Fold_API_34.avd" />
+            </handle>
+          </Target>
+        </DropdownSelection>
+        <DialogSelection />
       </SelectionState>
     </selectionStates>
   </component>

.idea/kotlinc.xml

@@ -1,6 +1,13 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="Kotlin2JvmCompilerArguments">
+    <option name="jvmTarget" value="1.8" />
+  </component>
+  <component name="KotlinCommonCompilerArguments">
+    <option name="apiVersion" value="2.0" />
+    <option name="languageVersion" value="2.0" />
+  </component>
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="1.9.0" />
+    <option name="version" value="2.0.10" />
   </component>
 </project>

app/build.gradle.kts

@@ -1,6 +1,11 @@
 plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.jetbrains.kotlin.android)
+    alias(libs.plugins.devtools.ksp)
+    alias(libs.plugins.compose.compiler)
+
+    id("kotlin-kapt")
+    alias(libs.plugins.hilt.android)
 }
 
 android {
@@ -40,7 +45,7 @@ android {
         compose = true
     }
     composeOptions {
-        kotlinCompilerExtensionVersion = "1.5.1"
+        kotlinCompilerExtensionVersion = "1.5.15"
     }
     packaging {
         resources {
@@ -50,7 +55,11 @@ android {
 }
 
 dependencies {
+    implementation(libs.hilt.android)
+    kapt(libs.hilt.android.compiler)
 
+
+    ksp(libs.androidx.room.compiler)
     implementation(libs.androidx.core.ktx)
     implementation(libs.androidx.lifecycle.runtime.ktx)
     implementation(libs.androidx.activity.compose)
@@ -59,7 +68,8 @@ dependencies {
     implementation(libs.androidx.ui.graphics)
     implementation(libs.androidx.ui.tooling.preview)
     implementation(libs.androidx.material3)
-    implementation(libs.androidx.datastore)
+    implementation(libs.androidx.room.runtime)
+    implementation(libs.androidx.room.ktx)
     testImplementation(libs.junit)
     androidTestImplementation(libs.androidx.junit)
     androidTestImplementation(libs.androidx.espresso.core)
@@ -68,3 +78,8 @@ dependencies {
     debugImplementation(libs.androidx.ui.tooling)
     debugImplementation(libs.androidx.ui.test.manifest)
 }
+
+// Allow references to generated code
+kapt {
+    correctErrorTypes = true
+}

app/src/main/AndroidManifest.xml

@@ -3,6 +3,7 @@
     xmlns:tools="http://schemas.android.com/tools">
 
     <application
+        android:name=".MyApplication"
         android:allowBackup="true"
         android:dataExtractionRules="@xml/data_extraction_rules"
         android:enableOnBackInvokedCallback="true"
@@ -12,7 +13,12 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.CoinCounter"
-        tools:targetApi="31">
+        tools:targetApi="35">
+        <activity
+            android:name=".WalletActivity"
+            android:exported="false"
+            android:label="@string/title_activity_wallet"
+            android:theme="@style/Theme.CoinCounter" />
         <activity
             android:name=".MainActivity"
             android:exported="true"

app/src/main/java/eu/m724/coincounter/MainActivity.kt

@@ -1,11 +1,13 @@
 package eu.m724.coincounter
 
+import android.content.Intent
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
+import androidx.activity.viewModels
 import androidx.compose.animation.AnimatedVisibility
-import androidx.compose.foundation.BorderStroke
+import androidx.compose.animation.core.animateFloatAsState
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -13,17 +15,15 @@ import androidx.compose.foundation.layout.ExperimentalLayoutApi
 import androidx.compose.foundation.layout.FlowRow
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.Row
-import androidx.compose.foundation.layout.Spacer
-import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.layout.fillMaxHeight
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.size
-import androidx.compose.foundation.layout.width
-import androidx.compose.foundation.lazy.LazyColumn
-import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.BasicTextField
+import androidx.compose.foundation.text.KeyboardActions
+import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Add
 import androidx.compose.material3.Button
@@ -31,33 +31,42 @@ import androidx.compose.material3.ButtonDefaults
 import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.Icon
-import androidx.compose.material3.IconButton
+import androidx.compose.material3.LocalTextStyle
 import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
-import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.draw.rotate
+import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import androidx.lifecycle.lifecycleScope
+import dagger.hilt.android.AndroidEntryPoint
+import eu.m724.coincounter.data.entity.Wallet
 import eu.m724.coincounter.ui.theme.CoinCounterTheme
+import kotlinx.coroutines.launch
 
+@AndroidEntryPoint
 class MainActivity : ComponentActivity() {
-    private lateinit var viewModel: MainViewModel
+    private val viewModel: MainViewModel by viewModels()
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        viewModel = MainViewModel(application)
-        viewModel.init()
+        lifecycleScope.launch {
+            viewModel.openEvent.collect {
+                openWallet(it)
+            }
+        }
 
         enableEdgeToEdge()
         setContent {
@@ -66,29 +75,43 @@ class MainActivity : ComponentActivity() {
                     Box(
                         modifier = Modifier.padding(innerPadding)
                     ) {
-                        App(viewModel)
+                        App(
+                            viewModel = viewModel,
+                            onClick = {
+                                openWallet(it.id)
+                            }
+                        )
                     }
                 }
             }
         }
     }
 
-    override fun onStop() {
-        super.onStop()
-        viewModel.saveAll()
+    private fun openWallet(walletId: Long) {
+        val intent = Intent(application.applicationContext, WalletActivity::class.java)
+        intent.putExtra("walletId", walletId)
+        startActivity(intent)
     }
 }
 
 @Composable
-fun App(viewModel: MainViewModel) {
-    val total by viewModel.totalBalance.collectAsState()
-    val wallets by viewModel.wallets.collectAsState()
+fun App(
+    viewModel: MainViewModel,
+    onClick: (Wallet) -> Unit
+) {
+    val total by viewModel.totalBalance.collectAsState(initial = 0)
+    val wallets by viewModel.wallets.collectAsState(initial = listOf())
 
     Column {
         BalanceView(total)
         WalletList(
             wallets = wallets,
-            onAdd = { viewModel.addWallet(it) }
+            onClick = {
+                onClick(it)
+            },
+            onAdd = {
+                viewModel.addWallet(it)
+            }
         )
     }
 }
@@ -117,170 +140,129 @@ fun BalanceView(balance: Int) {
     }
 }
 
-@Composable
-fun AddWalletBox(
-    onAdd: (String) -> Unit
-) {
-    var name by remember { mutableStateOf("") }
-
-    Box(
-        modifier = Modifier.fillMaxWidth(),
-        contentAlignment = Alignment.CenterEnd
-    ) {
-        Card(
-            modifier = Modifier
-                .fillMaxWidth()
-                .padding(16.dp, 2.dp),
-        ) {
-            Row(
-                modifier = Modifier
-                    .fillMaxWidth(),
-                horizontalArrangement = Arrangement.End,
-                verticalAlignment = Alignment.CenterVertically
-            ) {
-                Spacer(modifier = Modifier.width(16.dp))
-                BasicTextField(
-                    value = name,
-                    onValueChange = {
-                        name = it
-                    },
-                    modifier = Modifier
-                        .fillMaxWidth()
-                        .weight(1f),
-                    singleLine = true,
-                    textStyle = TextStyle.Default
-                )
-                IconButton(
-                    onClick = {
-                        if (name.isNotBlank()) {
-                            onAdd(name)
-                            name = ""
-                        }
-                    },
-                ) {
-                    Icon(
-                        imageVector = Icons.Filled.Add,
-                        contentDescription = "Add wallet"
-                    )
-                }
-            }
-        }
-    }
-}
-
+@OptIn(ExperimentalLayoutApi::class)
 @Composable
 fun WalletList(
     wallets: List<Wallet>,
+    onClick: (Wallet) -> Unit,
     onAdd: (String) -> Unit
 ) {
-    LazyColumn(
-        modifier = Modifier.width(500.dp)
+    FlowRow(
+        modifier = Modifier.fillMaxWidth(),
+        horizontalArrangement = Arrangement.Center,
+        maxItemsInEachRow = 3
     ) {
-        items(wallets) { wallet ->
-            WalletCard(wallet)
+        wallets.forEach { wallet ->
+            WalletCard(
+                wallet = wallet,
+                onClick = {
+                    onClick(wallet)
                 }
-        item {
-            AddWalletBox(onAdd)
+            )
         }
+        AddWalletButton(
+            onAdd = onAdd
+        )
     }
 }
 
 @Composable
-fun WalletCard(wallet: Wallet) {
-    var expanded by rememberSaveable { mutableStateOf(false) }
-    val balance by wallet.balance.collectAsState()
-
+fun WalletCard(
+    wallet: Wallet,
+    onClick: () -> Unit
+) {
     Button(
-        onClick = {
-            expanded = !expanded
-        },
-        modifier = Modifier
-            .fillMaxWidth()
-            .padding(16.dp, 2.dp),
+        modifier = Modifier.padding(8.dp),
+        onClick = onClick,
         colors = ButtonDefaults.buttonColors().copy(
             containerColor = CardDefaults.cardColors().containerColor,
             contentColor = CardDefaults.cardColors().contentColor
         ),
-        contentPadding = PaddingValues(8.dp, 2.dp)
+        shape = RoundedCornerShape(30),
+        contentPadding = PaddingValues(16.dp, 4.dp)
     ) {
-        Column {
-            AnimatedVisibility(visible = !expanded) {
-                Row(
-                    modifier = Modifier
-                        .fillMaxWidth()
-                        .padding(16.dp, 6.dp)
-                ) {
-                    Text(wallet.name)
-                    Spacer(modifier = Modifier
-                        .fillMaxWidth()
-                        .weight(1f))
-                    Text("%.2f zł".format(balance / 100.0))
-                }
-            }
-            AnimatedVisibility(visible = expanded) {
         Column(
-                    modifier = Modifier
-                        .fillMaxWidth()
-                        .padding(20.dp),
             horizontalAlignment = Alignment.CenterHorizontally
         ) {
-                    Text(wallet.name)
-                    Text(
-                        text = "%.2f zł".format(balance / 100.0),
-                        fontSize = 32.sp
-                    )
-                    UnitButtons(
-                        onClick = {
-                            wallet.fund(it)
-                        }
-                    )
-                }
-            }
+            Text(wallet.label)
+            Text(formatCurrency(wallet.balance))
         }
     }
 }
 
-@OptIn(ExperimentalLayoutApi::class)
 @Composable
-fun UnitButtons(
-    onClick: (Int) -> Unit
+fun AddWalletButton(
+    onAdd: (String) -> Unit
 ) {
-    val increments = listOf(1, 2, 5, 10, 20, 50, 100, 200, 500)
-    var add by rememberSaveable { mutableStateOf(true) }
+    var label by remember { mutableStateOf("") }
+    var expanded by remember { mutableStateOf(false) }
+    val angle by animateFloatAsState(
+        targetValue = if (expanded && label.isBlank()) 45f else 0f,
+        label = "Add button rotation"
+    )
+    val focusRequester = remember { FocusRequester() }
 
-    Row {
-        TextButton(
-            onClick = { add = false },
+    Card(
         modifier = Modifier
-                .size(48.dp)
-                .aspectRatio(1f),
-            border = if (!add) BorderStroke(1.dp, Color.Red) else null,
+            .padding(8.dp)
+            .height(48.dp)
     ) {
-            Text(
-                text = "-",
-                fontSize = 24.sp
-            )
-        }
-        Spacer(Modifier.width(5.dp))
-        TextButton(
-            onClick = { add = true },
+        Row(
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            AnimatedVisibility(
+                visible = expanded
+            ) {
+                BasicTextField(
+                    value = label,
+                    onValueChange = { label = it },
                     modifier = Modifier
-                .size(48.dp)
-                .aspectRatio(1f),
-            border = if (add) BorderStroke(1.dp, Color.Green) else null,
-            ) {
-            Text(
-                text = "+",
-                fontSize = 24.sp
+                        .padding(start = 16.dp)
+                        .focusRequester(focusRequester),
+                    textStyle = LocalTextStyle.current,
+                    keyboardOptions = KeyboardOptions(
+                        imeAction = ImeAction.Done
+                    ),
+                    keyboardActions = KeyboardActions(
+                        onDone = {
+                            expanded = false
+                            onAdd(label)
+                            label = ""
+                        }
+                    ),
+                    singleLine = true
                 )
+                LaunchedEffect(expanded) {
+                    focusRequester.requestFocus()
                 }
             }
-    FlowRow {
-        increments.forEach {
-            TextButton(onClick = {
-                onClick(if (add) it else -it)
-            }) {
-                Text(formatCurrency(it))
+            Button(
+                modifier = Modifier.fillMaxHeight(),
+                onClick = {
+                    if (!expanded) {
+                        expanded = true
+                    } else {
+                        if (label.isBlank()) {
+                            expanded = false
+                        } else {
+                            onAdd(label)
+                            expanded = false
+                        }
+                        label = ""
+                    }
+                },
+                colors = ButtonDefaults.buttonColors().copy(
+                    containerColor = CardDefaults.cardColors().containerColor,
+                    contentColor = CardDefaults.cardColors().contentColor
+                ),
+                shape = RoundedCornerShape(30),
+                contentPadding = PaddingValues(16.dp, 4.dp)
+            ) {
+                Icon(
+                    imageVector = Icons.Filled.Add,
+                    contentDescription = "Add wallet",
+                    modifier = Modifier.rotate(angle)
+                )
             }
         }
     }

app/src/main/java/eu/m724/coincounter/MainViewModel.kt

@@ -1,66 +1,34 @@
 package eu.m724.coincounter
 
-import android.app.Application
-import androidx.core.content.edit
-import androidx.lifecycle.AndroidViewModel
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.StateFlow
-import kotlinx.coroutines.flow.asStateFlow
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import dagger.hilt.android.lifecycle.HiltViewModel
+import eu.m724.coincounter.data.entity.Wallet
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.asSharedFlow
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
+import javax.inject.Inject
 
-class MainViewModel(
-    application: Application
-) : AndroidViewModel(application) {
-    private val _totalBalance: MutableStateFlow<Int> = MutableStateFlow(0)
-    val totalBalance: StateFlow<Int> = _totalBalance.asStateFlow()
+@HiltViewModel
+class MainViewModel @Inject constructor(
+    private val repository: WalletRepository
+) : ViewModel() {
+    val wallets: Flow<List<Wallet>> = repository.getAllWallets()
 
-    private val _wallets: MutableStateFlow<List<Wallet>> = MutableStateFlow(listOf())
-    val wallets: StateFlow<List<Wallet>> = _wallets.asStateFlow()
+    private val _openEvent = MutableSharedFlow<Long>()
+    val openEvent = _openEvent.asSharedFlow()
 
-    private val dataPreferences = application.getSharedPreferences("data", Application.MODE_PRIVATE)
-    private val walletsPreferences = application.getSharedPreferences("wallets", Application.MODE_PRIVATE)
-
-    private var highestId = 0
-
-    fun init() {
-        val savedWallets = dataPreferences.getStringSet("walletIds", null)
-
-        if (savedWallets != null) {
-            val savedWalletIds = savedWallets.map { it.toInt() }.sorted()
-            val w = arrayListOf<Wallet>()
-
-            savedWalletIds.forEach { id ->
-                val wallet = Wallet.fromPreferences(id, walletsPreferences) { wa, mo -> onWalletUpdate(wa, mo) }
-                w.add(wallet)
-                _totalBalance.value += wallet.balance.value
-                if (wallet.id > highestId)
-                    highestId = wallet.id
-            }
-
-            _wallets.value = w
-        } else {
-            _wallets.value = listOf(Wallet.default { wa, mo -> onWalletUpdate(wa, mo) })
-            _totalBalance.value = 2000
-        }
-    }
-
-    fun saveAll() {
-        dataPreferences.edit(true) {
-            putStringSet("walletIds", wallets.value.map { it.id.toString() }.toSet())
-        }
-
-
-        walletsPreferences.edit(true) {
-            wallets.value.forEach {
-                it.toPreferences(this)
-            }
-        }
+    val totalBalance: Flow<Int> = wallets.map { wallets ->
+        wallets.sumOf { it.balance }
     }
 
     fun addWallet(name: String) {
-        _wallets.value += Wallet(++highestId, name, 0) { wa, mo -> onWalletUpdate(wa, mo) }
-    }
-
-    private fun onWalletUpdate(wallet: Wallet, money: Int) {
-        _totalBalance.value += money
+        val wallet = Wallet(label = name)
+        viewModelScope.launch {
+            val id = repository.insertWallet(wallet)
+            _openEvent.emit(id)
+        }
     }
 }

app/src/main/java/eu/m724/coincounter/MyApplication.kt

@@ -0,0 +1,12 @@
+package eu.m724.coincounter
+
+import android.app.Application
+import dagger.hilt.android.HiltAndroidApp
+
+@HiltAndroidApp
+class MyApplication : Application() {
+
+    override fun onCreate() {
+        super.onCreate()
+    }
+}

app/src/main/java/eu/m724/coincounter/Wallet.kt

@@ -1,41 +0,0 @@
-package eu.m724.coincounter
-
-import android.content.SharedPreferences
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.StateFlow
-import kotlinx.coroutines.flow.asStateFlow
-
-class Wallet(
-    val id: Int,
-    val name: String,
-    balance: Int,
-    val onUpdate: (Wallet, Int) -> Unit
-) {
-    companion object {
-        fun default(onUpdate: (Wallet, Int) -> Unit): Wallet {
-            return Wallet(0, "Primary", 2000, onUpdate)
-        }
-
-        fun fromPreferences(id: Int, sharedPreferences: SharedPreferences, onUpdate: (Wallet, Int) -> Unit): Wallet {
-            return Wallet(
-                id,
-                sharedPreferences.getString("${id}_name", "Wallet")!!,
-                sharedPreferences.getInt("${id}_balance", 0),
-                onUpdate
-            )
-        }
-    }
-
-    fun toPreferences(editor: SharedPreferences.Editor) {
-        editor.putString("${id}_name", name)
-        editor.putInt("${id}_balance", balance.value)
-    }
-
-    private val _balance: MutableStateFlow<Int> = MutableStateFlow(balance)
-    val balance: StateFlow<Int> = _balance.asStateFlow()
-
-    fun fund(money: Int) {
-        _balance.value += money
-        onUpdate(this, money)
-    }
-}

app/src/main/java/eu/m724/coincounter/WalletActivity.kt

@@ -0,0 +1,291 @@
+package eu.m724.coincounter
+
+import android.os.Bundle
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.activity.viewModels
+import androidx.compose.foundation.gestures.detectTapGestures
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Create
+import androidx.compose.material3.Card
+import androidx.compose.material3.FloatingActionButton
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.material3.TextField
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import androidx.compose.ui.window.Dialog
+import dagger.hilt.android.AndroidEntryPoint
+import eu.m724.coincounter.ui.theme.CoinCounterTheme
+import java.text.DateFormat
+import java.util.Date
+import java.util.Locale
+
+@AndroidEntryPoint
+class WalletActivity : ComponentActivity() {
+    private val viewModel: WalletViewModel by viewModels()
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        val walletId = intent.getLongExtra("walletId", 0)
+        viewModel.init(walletId)
+
+        enableEdgeToEdge()
+        setContent {
+            CoinCounterTheme {
+                var transactionDialogShown by rememberSaveable { mutableStateOf(false) }
+                if (transactionDialogShown) {
+                    TransactionDialog(
+                        onDismiss = { transactionDialogShown = false },
+                        onConfirm = { label, value ->
+                            transactionDialogShown = false
+                            viewModel.transact(value, label)
+                        }
+                    )
+                }
+                Scaffold(
+                    modifier = Modifier.fillMaxSize(),
+                    floatingActionButton = {
+                        FloatingActionButton(onClick = {
+                            transactionDialogShown = true
+                        }) {
+                            Icon(Icons.Filled.Create, "New transaction")
+                        }
+                    }
+                ) { innerPadding ->
+                    Column(
+                        modifier = Modifier.padding(innerPadding)
+                    ) {
+                        App(
+                            viewModel = viewModel,
+                            finish = { finish() }
+                        )
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+fun App(
+    viewModel: WalletViewModel,
+    finish: () -> Unit
+) {
+    val walletState by viewModel.wallet.collectAsState(initial = null)
+    val wallet = walletState
+
+    var actionsVisible by rememberSaveable { mutableStateOf(false) }
+
+    if (actionsVisible) {
+        ActionsDialog(
+            onDismiss = { actionsVisible = false },
+            onDelete = {
+                viewModel.delete()
+                finish()
+            }
+        )
+    }
+
+    if (wallet != null) {
+        Column(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalAlignment = Alignment.CenterHorizontally
+        ) {
+            Spacer(modifier = Modifier.height(50.dp))
+            Text(
+                text = wallet.label,
+                modifier = Modifier.pointerInput(Unit) {
+                    detectTapGestures(
+                        onLongPress = {
+                            actionsVisible = true
+                        }
+                    )
+                }
+            )
+
+            Spacer(modifier = Modifier.height(4.dp))
+            Card {
+                Row(
+                    modifier = Modifier.padding(16.dp, 8.dp),
+                    verticalAlignment = Alignment.Bottom,
+                ) {
+                    Text(
+                        text = "%.2f".format(wallet.balance / 100.0),
+                        fontSize = 32.sp
+                    )
+                    Text(
+                        text = "zł",
+                        fontSize = 14.sp
+                    )
+                }
+            }
+            Spacer(modifier = Modifier.height(50.dp))
+
+            TransactionList(viewModel = viewModel)
+        }
+    }
+}
+
+@Composable
+fun TransactionList(viewModel: WalletViewModel) {
+    val transactions by viewModel.transactions.collectAsState(initial = listOf())
+
+    LazyColumn {
+        items(transactions) {
+            Card(
+                modifier = Modifier
+                    .width(200.dp)
+                    .padding(8.dp)
+            ) {
+                Row(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .padding(8.dp, 2.dp),
+                    horizontalArrangement = Arrangement.Center
+                ) {
+                    Text(it.label ?: it.id.toString())
+
+                    Spacer(modifier = Modifier
+                        .fillMaxWidth()
+                        .weight(1f))
+
+                    Text(
+                        text = "%.2f".format(it.value / 100.0),
+                        color = if (it.value < 0) MaterialTheme.colorScheme.error else Color.Unspecified
+                    )
+                }
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.Center
+                ) {
+                    Text(
+                        DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.SHORT, Locale.getDefault())
+                            .format(Date(it.timestamp))
+                    )
+                }
+            }
+        }
+    }
+}
+
+
+@Composable
+fun TransactionDialog(
+    onDismiss: () -> Unit,
+    onConfirm: (String, Int) -> Unit
+) {
+    var label by rememberSaveable { mutableStateOf("") }
+    var value by rememberSaveable { mutableStateOf("0") }
+
+    Dialog(
+        onDismissRequest = {
+            label = ""
+            onDismiss()
+        }
+    ) {
+        Card(
+            modifier = Modifier
+                .fillMaxWidth(),
+        ) {
+            Column(
+                modifier = Modifier.padding(16.dp)
+            ) {
+                Row {
+                    TextField(
+                        value = label,
+                        onValueChange = { label = it },
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .weight(1f),
+                        supportingText = { Text("Label") },
+                        singleLine = true
+                    )
+                    Spacer(modifier = Modifier.width(6.dp))
+                    TextField(
+                        value = value,
+                        onValueChange = { value = it },
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .weight(1f),
+                        supportingText = { Text("Value") },
+                        keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
+                        singleLine = true
+                    )
+                }
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.End
+                ) {
+                    TextButton(onClick = {
+                        label = ""
+                        onDismiss()
+                    }) {
+                        Text(text = "Cancel")
+                    }
+                    TextButton(onClick = {
+                        onConfirm(label, (value.toFloat() * 100).toInt())
+                    }) {
+                        Text("Create transaction")
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+fun ActionsDialog(
+    onDismiss: () -> Unit,
+    onDelete: () -> Unit
+) {
+    Dialog(
+        onDismissRequest = {
+            onDismiss()
+        }
+    ) {
+        Card(
+            modifier = Modifier
+                .fillMaxWidth(),
+        ) {
+            Column(
+                modifier = Modifier.padding(16.dp)
+            ) {
+                TextButton(onClick = onDelete) {
+                    Text("Delete wallet")
+                }
+                TextButton(onClick = onDismiss) {
+                    Text("Cancel")
+                }
+            }
+        }
+    }
+}

app/src/main/java/eu/m724/coincounter/WalletRepository.kt

@@ -0,0 +1,37 @@
+package eu.m724.coincounter
+
+import android.content.Context
+import androidx.room.Room
+import dagger.hilt.android.qualifiers.ApplicationContext
+import eu.m724.coincounter.data.AppDatabase
+import eu.m724.coincounter.data.dao.TransactionDao
+import eu.m724.coincounter.data.dao.WalletDao
+import eu.m724.coincounter.data.entity.Transaction
+import eu.m724.coincounter.data.entity.Wallet
+import kotlinx.coroutines.flow.Flow
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class WalletRepository @Inject constructor(
+    @ApplicationContext private val applicationContext: Context
+) {
+    private val database: AppDatabase = Room.databaseBuilder(
+        applicationContext,
+        AppDatabase::class.java,
+        "database-v1"
+    ).build()
+    private val walletDao: WalletDao = database.walletDao()
+    private val transactionDao: TransactionDao = database.transactionDao()
+
+    fun getAllWallets(): Flow<List<Wallet>> = walletDao.getAllWallets()
+    fun getWalletById(id: Long): Flow<Wallet> = walletDao.getWalletById(id)
+
+    suspend fun insertWallet(wallet: Wallet): Long = walletDao.insertWallet(wallet)
+    fun updateWallet(wallet: Wallet) = walletDao.updateWallet(wallet)
+    fun deleteWallet(wallet: Wallet) = walletDao.deleteWallet(wallet)
+
+    fun getWalletTransactions(walletId: Long) = transactionDao.getWalletTransactions(walletId)
+
+    fun insertTransaction(transaction: Transaction) = transactionDao.insertTransaction(transaction)
+}

app/src/main/java/eu/m724/coincounter/WalletViewModel.kt

@@ -0,0 +1,53 @@
+package eu.m724.coincounter
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import dagger.hilt.android.lifecycle.HiltViewModel
+import eu.m724.coincounter.data.entity.Transaction
+import eu.m724.coincounter.data.entity.Wallet
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.launch
+import javax.inject.Inject
+import kotlin.properties.Delegates
+
+@HiltViewModel
+class WalletViewModel @Inject constructor(
+    private val repository: WalletRepository
+) : ViewModel() {
+    private var walletId by Delegates.notNull<Long>()
+
+    lateinit var wallet: Flow<Wallet>
+    lateinit var transactions: Flow<List<Transaction>>
+
+    fun init(walletId: Long) {
+        this.walletId = walletId
+        wallet = repository.getWalletById(walletId)
+        transactions = repository.getWalletTransactions(walletId)
+    }
+
+    fun delete() {
+        viewModelScope.launch(Dispatchers.IO) {
+            repository.deleteWallet(wallet.first())
+        }
+    }
+
+    fun transact(value: Int, label: String?) {
+        val transaction = Transaction(
+            walletId = walletId,
+            value = value,
+            label = label
+        )
+
+        viewModelScope.launch(Dispatchers.IO) {
+            val wallet = wallet.first()
+            wallet.let {
+                repository.updateWallet(
+                    wallet.copy(balance = wallet.balance + value)
+                )
+            }
+            repository.insertTransaction(transaction)
+        }
+    }
+}

app/src/main/java/eu/m724/coincounter/data/AppDatabase.kt

@@ -0,0 +1,14 @@
+package eu.m724.coincounter.data
+
+import androidx.room.Database
+import androidx.room.RoomDatabase
+import eu.m724.coincounter.data.dao.TransactionDao
+import eu.m724.coincounter.data.dao.WalletDao
+import eu.m724.coincounter.data.entity.Transaction
+import eu.m724.coincounter.data.entity.Wallet
+
+@Database(entities = [Wallet::class, Transaction::class], version = 1)
+abstract class AppDatabase : RoomDatabase() {
+    abstract fun walletDao(): WalletDao
+    abstract fun transactionDao(): TransactionDao
+}

app/src/main/java/eu/m724/coincounter/data/dao/TransactionDao.kt

@@ -0,0 +1,26 @@
+package eu.m724.coincounter.data.dao
+
+import androidx.room.Dao
+import androidx.room.Delete
+import androidx.room.Insert
+import androidx.room.Query
+import eu.m724.coincounter.data.entity.Transaction
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface TransactionDao {
+    @Query("SELECT * FROM transactions WHERE walletId = :walletId AND timestamp > :after ORDER BY timestamp DESC LIMIT :limit")
+    fun getWalletTransactions(walletId: Long, after: Long = 0, limit: Int = 10): Flow<List<Transaction>>
+
+    @Insert
+    fun insertTransaction(transaction: Transaction)
+
+    @Insert
+    fun insertTransactions(transactions: List<Transaction>)
+
+    @Delete
+    fun deleteTransaction(transaction: Transaction)
+
+    @Insert
+    fun deleteTransactions(transactions: List<Transaction>)
+}

app/src/main/java/eu/m724/coincounter/data/dao/WalletDao.kt

@@ -0,0 +1,36 @@
+package eu.m724.coincounter.data.dao
+
+import androidx.room.Dao
+import androidx.room.Delete
+import androidx.room.Insert
+import androidx.room.Query
+import androidx.room.Update
+import eu.m724.coincounter.data.entity.Wallet
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface WalletDao {
+    @Query("SELECT * FROM wallets")
+    fun getAllWallets(): Flow<List<Wallet>>
+
+    @Query("SELECT * FROM wallets WHERE id = (:id)")
+    fun getWalletById(id: Long): Flow<Wallet>
+
+    @Insert
+    suspend fun insertWallet(wallet: Wallet): Long
+
+    @Insert
+    suspend fun insertWallets(wallets: List<Wallet>): LongArray
+
+    @Update
+    fun updateWallet(wallet: Wallet)
+
+    @Update
+    fun updateWallets(wallets: List<Wallet>)
+
+    @Delete
+    fun deleteWallet(wallet: Wallet)
+
+    @Delete
+    fun deleteWallets(wallet: List<Wallet>)
+}

app/src/main/java/eu/m724/coincounter/data/entity/Transaction.kt

@@ -0,0 +1,40 @@
+package eu.m724.coincounter.data.entity
+
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.PrimaryKey
+
+/**
+ * represents adding or removing money from a wallet,
+ * with optional metadata
+ */
+@Entity(
+    tableName = "transactions",
+    foreignKeys = [
+        ForeignKey(
+            entity = Wallet::class,
+            parentColumns = ["id"],
+            childColumns = ["walletId"],
+            onDelete = ForeignKey.CASCADE
+        )
+    ]
+)
+data class Transaction(
+    /** used for internal reference */
+    @PrimaryKey(autoGenerate = true)
+    val id: Long = 0,
+
+    /**
+     * the wallet id that money was used from
+     */
+    val walletId: Long,
+
+    /** how much cents added (positive) or removed (negative) */
+    val value: Int,
+
+    /** label of the transaction, set by user */
+    val label: String? = null,
+
+    /** timestamp in unix milllis when the transaction was performed */
+    val timestamp: Long = System.currentTimeMillis()
+)

app/src/main/java/eu/m724/coincounter/data/entity/Wallet.kt

@@ -0,0 +1,17 @@
+package eu.m724.coincounter.data.entity
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "wallets")
+data class Wallet(
+    @PrimaryKey(autoGenerate = true)
+    val id: Long = 0,
+
+    /** the wallet label set by user */
+    var label: String = "Wallet",
+
+    /** balance in cents
+     * for example 123 cents = 1.23 euro or any other currency */
+    var balance: Int = 0
+)

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

@@ -1,4 +1,5 @@
 <resources>
     <string name="app_name">Coin Counter</string>
     <string name="title_activity_main">MainActivity</string>
+    <string name="title_activity_wallet">WalletActivity</string>
 </resources>

build.gradle.kts

@@ -2,4 +2,7 @@
 plugins {
     alias(libs.plugins.android.application) apply false
     alias(libs.plugins.jetbrains.kotlin.android) apply false
+    alias(libs.plugins.devtools.ksp) apply false
+    alias(libs.plugins.compose.compiler) apply false
+    alias(libs.plugins.hilt.android) apply false
 }

gradle/libs.versions.toml

@@ -1,18 +1,22 @@
 [versions]
-agp = "8.5.1"
-datastore = "1.1.1"
-kotlin = "1.9.0"
-coreKtx = "1.10.1"
+agp = "8.5.2"
+kotlin = "2.0.10"
+coreKtx = "1.13.1"
 junit = "4.13.2"
-junitVersion = "1.1.5"
-espressoCore = "3.5.1"
-lifecycleRuntimeKtx = "2.6.1"
-activityCompose = "1.8.0"
-composeBom = "2024.04.01"
+junitVersion = "1.2.1"
+espressoCore = "3.6.1"
+lifecycleRuntimeKtx = "2.8.4"
+activityCompose = "1.9.1"
+composeBom = "2024.06.00"
+room = "2.6.1"
+ksp = "2.0.10-1.0.24"
+hilt = "2.44"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
-androidx-datastore = { module = "androidx.datastore:datastore", version.ref = "datastore" }
+androidx-room-compiler = { module = "androidx.room:room-compiler", version.ref = "room" }
+androidx-room-runtime = { module = "androidx.room:room-runtime", version.ref = "room" }
+androidx-room-ktx = { module = "androidx.room:room-ktx", version.ref = "room" }
 junit = { group = "junit", name = "junit", version.ref = "junit" }
 androidx-junit = { group = "androidx.test.ext", name = "junit", version.ref = "junitVersion" }
 androidx-espresso-core = { group = "androidx.test.espresso", name = "espresso-core", version.ref = "espressoCore" }
@@ -26,8 +30,13 @@ androidx-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-toolin
 androidx-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
 androidx-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
 androidx-material3 = { group = "androidx.compose.material3", name = "material3" }
+hilt-android = { group = "com.google.dagger", name = "hilt-android", version.ref = "hilt"}
+hilt-android-compiler = { group = "com.google.dagger", name = "hilt-android-compiler", version.ref = "hilt"}
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 jetbrains-kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
+devtools-ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
+compose-compiler = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
+hilt-android = { id = "com.google.dagger.hilt.android", version.ref = "hilt"}