Refactor: Replace Runnable with TimerTask and update dependencies

This commit refactors the timer scheduling logic by replacing `Runnable` with `TimerTask` for better clarity and consistency with the `java.util.Timer` API.

Key changes include:
- Replaced `Runnable` with `TimerTask` in `CellState`, `ICellState`, and `MainService`.
- Simplified timer scheduling logic in `CellState`.
- Updated Gradle wrapper to version 9.1.0.
- Bumped `google-services` plugin to 4.4.4.
- Increased app version to 2.1.3.
- Improved Android 13+ notification permission handling.
- Minor code cleanup, including removing unused resources and imports.

Author: softartdev

app/build.gradle

@@ -16,13 +16,14 @@ android {
         applicationId "com.softartdev.conwaysgameoflife"
         minSdkVersion 23
         targetSdkVersion 36
-        versionCode 212
-        versionName '2.1.2'
+        versionCode 213
+        versionName '2.1.3'
         resourceConfigurations += ['en']
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
     buildFeatures {
         viewBinding true
+        buildConfig true
     }
     signingConfigs {
         config {

app/src/androidTest/java/com/softartdev/conwaysgameoflife/ExampleInstrumentedTest.java

@@ -1,5 +1,7 @@
 package com.softartdev.conwaysgameoflife;
 
+import static org.junit.Assert.assertEquals;
+
 import android.content.Context;
 
 import androidx.test.ext.junit.runners.AndroidJUnit4;
@@ -8,11 +10,8 @@
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
-import static org.junit.Assert.assertEquals;
-
 /**
  * Instrumented test, which will execute on an Android device.
- *
  * See [testing documentation](http://d.android.com/tools/testing).
  */
 @RunWith(AndroidJUnit4.class)

app/src/main/java/com/softartdev/conwaysgameoflife/MainService.kt

@@ -23,6 +23,7 @@ import com.softartdev.conwaysgameoflife.model.CellState
 import com.softartdev.conwaysgameoflife.model.ICellState
 import com.softartdev.conwaysgameoflife.ui.MainActivity
 import timber.log.Timber
+import java.util.TimerTask
 
 
 class MainService : Service() {
@@ -44,7 +45,7 @@ class MainService : Service() {
         super.onCreate()
         Timber.d("onCreate")
         createNotificationChannel(applicationContext, notificationManager)
-        val runnable: Runnable = object : Runnable {
+        val timerTask = object : TimerTask() {
             val uiHandler = Handler(Looper.myLooper()!!)
             override fun run() {
                 Timber.d("Process generation step: %s", iCellState.countGeneration)//FIXME await on idle
@@ -58,7 +59,7 @@ class MainService : Service() {
                 } else notificationManager.cancelAll()
             }
         }
-        iCellState.setRunnable(runnable)
+        iCellState.setTimerTask(timerTask)
     }
 
     override fun onStartCommand(intent: Intent, flags: Int, startId: Int): Int {

app/src/main/java/com/softartdev/conwaysgameoflife/model/CellState.java

@@ -11,7 +11,7 @@ public class CellState implements ICellState {
     private static final int SHOW_DELAY = 500;
     private volatile int period = SHOW_DELAY;
     private Timer timer;//FIXME: consider more optimized alternatives for such loop
-    private Runnable runnable;
+    private TimerTask timerTask;
     private final boolean[][] lifeGeneration = new boolean[LIFE_SIZE][LIFE_SIZE];
     private final boolean[][] nextGeneration = new boolean[LIFE_SIZE][LIFE_SIZE];
     private int countGeneration = 0;
@@ -26,31 +26,24 @@ public int getPeriod() {
         return period;
     }
 
-    @Override
-    public void scheduleTimer(Runnable runnable) {
+    private void scheduleTimer() {
         if (timer == null) {
             timer = new Timer();
         }
-        this.runnable = runnable;
-        TimerTask timerTask = new TimerTask() {
-            @Override
-            public void run() {
-                CellState.this.runnable.run();
-            }
-        };
+        if (timerTask == null) return;
         timer.schedule(timerTask, 0L, period);
     }
 
     @Override
-    public void setRunnable(Runnable runnable) {
-        this.runnable = runnable;
+    public void setTimerTask(TimerTask timerTask) {
+        this.timerTask = timerTask;
     }
 
     @Override
     public void updatePeriod(int period) {
         cancelTimer();
         this.period = period;
-        scheduleTimer(this.runnable);
+        scheduleTimer();
     }
 
     @Override
@@ -63,7 +56,7 @@ public void cancelTimer() {
 
     @Override
     public void resumeTimer() {
-        scheduleTimer(runnable);
+        scheduleTimer();
     }
 
     @Override

app/src/main/java/com/softartdev/conwaysgameoflife/model/ICellState.java

@@ -1,9 +1,10 @@
 package com.softartdev.conwaysgameoflife.model;
 
+import java.util.TimerTask;
+
 public interface ICellState {
     int getPeriod();
-    void scheduleTimer(Runnable runnable);
-    void setRunnable(Runnable runnable);
+    void setTimerTask(TimerTask timerTask);
     void updatePeriod(int period);
     void cancelTimer();
     void resumeTimer();

app/src/main/java/com/softartdev/conwaysgameoflife/ui/CellLayout.kt

@@ -3,7 +3,6 @@ package com.softartdev.conwaysgameoflife.ui
 import android.content.Context
 import android.util.AttributeSet
 import android.view.View
-import android.view.View.OnClickListener
 import android.widget.GridLayout
 import com.softartdev.conwaysgameoflife.model.CellState.LIFE_SIZE
 

app/src/main/java/com/softartdev/conwaysgameoflife/ui/MainActivity.kt

@@ -11,6 +11,7 @@ import android.view.Menu
 import android.view.MenuItem
 import android.widget.SeekBar
 import androidx.activity.enableEdgeToEdge
+import androidx.activity.result.ActivityResultLauncher
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
@@ -25,10 +26,13 @@ import com.softartdev.conwaysgameoflife.model.CellState
 import com.softartdev.conwaysgameoflife.model.ICellState
 
 class MainActivity : AppCompatActivity() {
-
-    private lateinit var binding: ActivityMainBinding
-
     private val iCellState: ICellState = CellState.getInstance()
+    private val activityResultLauncher: ActivityResultLauncher<String?> = registerForActivityResult(
+        ActivityResultContracts.RequestPermission(),
+        this@MainActivity::onPermResult
+    )
+    private var toggle: Boolean = false // To start game after permission granted
+    private lateinit var binding: ActivityMainBinding
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -46,7 +50,8 @@ class MainActivity : AppCompatActivity() {
         }
         updateStartButtonText()
         binding.mainStartButton.setOnClickListener {
-            if (checkNotificationPermissionGranted(toggle = true)) toggleGame()
+            toggle = true
+            if (checkNotificationPermissionGranted()) toggleGame()
         }
         binding.mainStepButton.setOnClickListener {
             val processed = iCellState.processNextGeneration() ?: return@setOnClickListener
@@ -96,26 +101,29 @@ class MainActivity : AppCompatActivity() {
         }
     }
 
-    private fun checkNotificationPermissionGranted(toggle: Boolean = false): Boolean = when {
+    private fun checkNotificationPermissionGranted(): Boolean = when {
         Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU -> when {
             ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) == PackageManager.PERMISSION_GRANTED -> true
             ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.POST_NOTIFICATIONS) -> {
                 showNotificationPermissionExplanation()
                 false
             }
             else -> {
-                registerForActivityResult(ActivityResultContracts.RequestPermission()) { isGranted: Boolean ->
-                    when {
-                        isGranted -> if (toggle) toggleGame()
-                        else -> showNotificationPermissionExplanation()
-                    }
-                }.launch(Manifest.permission.POST_NOTIFICATIONS)
+                activityResultLauncher.launch(Manifest.permission.POST_NOTIFICATIONS)
                 false
             }
         }
         else -> true
     }
 
+    private fun onPermResult(isGranted: Boolean) = when {
+        isGranted -> {
+            if (toggle) toggleGame()
+            toggle = false
+        }
+        else -> showNotificationPermissionExplanation()
+    }
+
     private fun toggleGame() {
         with(iCellState) { if (toggleGoNextGeneration()) cancelTimer() else resumeTimer() }
         updateStartButtonText()

app/src/main/java/com/softartdev/conwaysgameoflife/ui/MainServiceConnection.kt

@@ -4,7 +4,6 @@ import android.content.ComponentName
 import android.content.ServiceConnection
 import android.os.IBinder
 import com.softartdev.conwaysgameoflife.MainService
-import com.softartdev.conwaysgameoflife.model.ICellState
 
 object MainServiceConnection : ServiceConnection {
 

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

@@ -1,6 +1,2 @@
 <?xml version="1.0" encoding="utf-8"?>
-<resources>
-    <color name="colorPrimary">#3F51B5</color>
-    <color name="colorPrimaryDark">#303F9F</color>
-    <color name="colorAccent">#FF4081</color>
-</resources>
+<resources />

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

@@ -6,11 +6,12 @@
     <string name="random">Randomize</string>
     <string name="clean">Clean</string>
     <string name="rules_title">Rules</string>
-    <string name="rules_text">
-        \n- Any live cell with fewer than 2 live neighbours dies, as if caused by under-population.
-        \n- Any live cell with more than 3 live neighbours dies, as if by over-population.
-        \n- Any live cell with 2 or 3 live neighbours lives on to the next generation.
-        \n- Any dead cell with exactly 3 live neighbours becomes a live cell, as if by reproduction.</string>
+    <string name="rules_text"><![CDATA[
+        • Any live cell with fewer than 2 live neighbours dies, as if caused by under-population.\n
+        • Any live cell with more than 3 live neighbours dies, as if by over-population.\n
+        • Any live cell with 2 or 3 live neighbours lives on to the next generation.\n
+        • Any dead cell with exactly 3 live neighbours becomes a live cell, as if by reproduction.
+    ]]></string>
     <string name="steps">Steps: %1$d</string>
     <string name="notification_channel_id">conway_channel</string>
     <string name="notification_channel_name">Game notification channel</string>