Fix OutOfMemoryError when loading a game and another is already loaded (#7306)

* Fix OutOfMemoryError when loading a game and another is already loaded

* Fix merge error...

build.gradle.kts

@@ -24,7 +24,7 @@ buildscript {
     dependencies {
         classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:${com.unciv.build.BuildConfig.kotlinVersion}")
         classpath("de.richsource.gradle.plugins:gwt-gradle-plugin:0.6")
-        classpath("com.android.tools.build:gradle:7.0.4")
+        classpath("com.android.tools.build:gradle:7.1.3")
         classpath("com.mobidevelop.robovm:robovm-gradle-plugin:2.3.1")
 
         // This is for wrapping the .jar file into a standalone executable

core/src/com/unciv/UncivGame.kt

@@ -37,6 +37,7 @@ import com.unciv.utils.concurrency.launchOnGLThread
 import com.unciv.utils.concurrency.withGLContext
 import com.unciv.utils.concurrency.withThreadPoolContext
 import com.unciv.utils.debug
+import kotlinx.coroutines.CancellationException
 import java.io.PrintWriter
 import java.util.*
 import kotlin.collections.ArrayDeque
@@ -405,6 +406,9 @@ class UncivGame(parameters: UncivGameParameters) : Game() {
 
     /** Handles an uncaught exception or error. First attempts a platform-specific handler, and if that didn't handle the exception or error, brings the game to a [CrashScreen]. */
     fun handleUncaughtThrowable(ex: Throwable) {
+        if (ex is CancellationException) {
+            return // kotlin coroutines use this for control flow... so we can just ignore them.
+        }
         Log.error("Uncaught throwable", ex)
         try {
             PrintWriter(files.fileWriter("lasterror.txt")).use {

core/src/com/unciv/ui/UncivStage.kt

@@ -24,6 +24,7 @@ class UncivStage(viewport: Viewport) : Stage(viewport) {
         private set
 
     private val events = EventBus.EventReceiver()
+
     init {
         lastKnownVisibleArea = Rectangle(0f, 0f, width, height)
         events.receive(VisibleAreaChanged::class) {
@@ -35,10 +36,15 @@ class UncivStage(viewport: Viewport) : Stage(viewport) {
     override fun dispose() {
         events.stopReceiving()
         super.dispose()
+
+        /** [Stage.dispose] is supposed to clear all references it holds. But it forgets the mouse over properties:
+         the [Stage.mouseOverActor] and [Stage.pointerOverActors]. [Stage.act] updates those properties,
+         and since there aren't any children left, sets all those properties to `null`. */
+        super.act()
     }
 
     override fun draw() =
-        { super.draw() }.wrapCrashHandlingUnit()()
+            { super.draw() }.wrapCrashHandlingUnit()()
 
     /** libGDX has no built-in way to disable/enable pointer enter/exit events. It is simply being done in [Stage.act]. So to disable this, we have
      * to replicate the [Stage.act] method without the code for pointer enter/exit events. This is of course inherently brittle, but the only way. */
@@ -54,31 +60,31 @@ class UncivStage(viewport: Viewport) : Stage(viewport) {
     }.wrapCrashHandlingUnit()()
 
     override fun act(delta: Float) =
-        { super.act(delta) }.wrapCrashHandlingUnit()()
+            { super.act(delta) }.wrapCrashHandlingUnit()()
 
     override fun touchDown(screenX: Int, screenY: Int, pointer: Int, button: Int) =
-        { super.touchDown(screenX, screenY, pointer, button) }.wrapCrashHandling()() ?: true
+            { super.touchDown(screenX, screenY, pointer, button) }.wrapCrashHandling()() ?: true
 
     override fun touchDragged(screenX: Int, screenY: Int, pointer: Int) =
-        { super.touchDragged(screenX, screenY, pointer) }.wrapCrashHandling()() ?: true
+            { super.touchDragged(screenX, screenY, pointer) }.wrapCrashHandling()() ?: true
 
     override fun touchUp(screenX: Int, screenY: Int, pointer: Int, button: Int) =
-        { super.touchUp(screenX, screenY, pointer, button) }.wrapCrashHandling()() ?: true
+            { super.touchUp(screenX, screenY, pointer, button) }.wrapCrashHandling()() ?: true
 
     override fun mouseMoved(screenX: Int, screenY: Int) =
-        { super.mouseMoved(screenX, screenY) }.wrapCrashHandling()() ?: true
+            { super.mouseMoved(screenX, screenY) }.wrapCrashHandling()() ?: true
 
     override fun scrolled(amountX: Float, amountY: Float) =
-        { super.scrolled(amountX, amountY) }.wrapCrashHandling()() ?: true
+            { super.scrolled(amountX, amountY) }.wrapCrashHandling()() ?: true
 
     override fun keyDown(keyCode: Int) =
-        { super.keyDown(keyCode) }.wrapCrashHandling()() ?: true
+            { super.keyDown(keyCode) }.wrapCrashHandling()() ?: true
 
     override fun keyUp(keyCode: Int) =
-        { super.keyUp(keyCode) }.wrapCrashHandling()() ?: true
+            { super.keyUp(keyCode) }.wrapCrashHandling()() ?: true
 
     override fun keyTyped(character: Char) =
-        { super.keyTyped(character) }.wrapCrashHandling()() ?: true
+            { super.keyTyped(character) }.wrapCrashHandling()() ?: true
 
     class VisibleAreaChanged(
         val visibleArea: Rectangle

core/src/com/unciv/ui/worldscreen/WorldScreen.kt

@@ -212,8 +212,9 @@ class WorldScreen(
     }
 
     override fun dispose() {
-        super.dispose()
         events.stopReceiving()
+        statusButtons.dispose()
+        super.dispose()
     }
 
     private fun addKeyboardPresses() {

core/src/com/unciv/ui/worldscreen/status/MultiplayerStatusButton.kt

@@ -11,6 +11,7 @@ import com.badlogic.gdx.scenes.scene2d.ui.Image
 import com.badlogic.gdx.scenes.scene2d.ui.Label
 import com.badlogic.gdx.scenes.scene2d.ui.Stack
 import com.badlogic.gdx.utils.Align
+import com.badlogic.gdx.utils.Disposable
 import com.unciv.UncivGame
 import com.unciv.logic.event.EventBus
 import com.unciv.logic.multiplayer.HasMultiplayerGameName
@@ -26,14 +27,15 @@ import com.unciv.ui.utils.extensions.onClick
 import com.unciv.ui.utils.extensions.setSize
 import com.unciv.utils.concurrency.Concurrency
 import com.unciv.utils.concurrency.launchOnGLThread
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.delay
 import java.time.Duration
 import java.time.Instant
 
 class MultiplayerStatusButton(
-    /*val*/ screen: BaseScreen,
+    screen: BaseScreen,
     curGame: OnlineMultiplayerGame?
-) : Button(BaseScreen.skin) {
+) : Button(BaseScreen.skin), Disposable {
     private var curGameName = curGame?.name
     private val multiplayerImage = createMultiplayerImage()
     private val loadingImage = createLoadingImage()
@@ -43,6 +45,7 @@ class MultiplayerStatusButton(
     private var loadingStarted: Instant? = null
 
     private val events = EventBus.EventReceiver()
+    private var loadStopJob: Job? = null
 
     init {
         turnIndicatorCell = add().padTop(10f).padBottom(10f)
@@ -96,7 +99,7 @@ class MultiplayerStatusButton(
         } else {
             Duration.ZERO
         }
-        Concurrency.run("Hide loading indicator") {
+        loadStopJob = Concurrency.run("Hide loading indicator") {
             delay(waitFor.toMillis())
             launchOnGLThread {
                 loadingImage.clearActions()
@@ -147,11 +150,18 @@ class MultiplayerStatusButton(
             turnIndicator.flash()
         }
     }
+
+    override fun dispose() {
+        events.stopReceiving()
+        turnIndicator.dispose()
+        loadStopJob?.cancel()
+    }
 }
 
-private class TurnIndicator : HorizontalGroup() {
+private class TurnIndicator : HorizontalGroup(), Disposable {
     val gameAmount = Label("2", BaseScreen.skin)
     val image: Image
+    private var job: Job? = null
     init {
         image = ImageGetter.getImage("OtherIcons/ExclamationMark")
         image.setSize(30f)
@@ -175,11 +185,15 @@ private class TurnIndicator : HorizontalGroup() {
         if (alternations == 0) return
         gameAmount.color = nextColor
         image.color = nextColor
-        Concurrency.run("StatusButton color flash") {
+        job = Concurrency.run("StatusButton color flash") {
             delay(500)
             launchOnGLThread {
                 flash(alternations - 1, nextColor, curColor)
             }
         }
     }
+
+    override fun dispose() {
+        job?.cancel()
+    }
 }

core/src/com/unciv/ui/worldscreen/status/StatusButtons.kt

@@ -1,11 +1,12 @@
 package com.unciv.ui.worldscreen.status
 
 import com.badlogic.gdx.scenes.scene2d.ui.HorizontalGroup
+import com.badlogic.gdx.utils.Disposable
 
 class StatusButtons(
     nextTurnButton: NextTurnButton,
     multiplayerStatusButton: MultiplayerStatusButton? = null
-) : HorizontalGroup() {
+) : HorizontalGroup(), Disposable {
     var multiplayerStatusButton: MultiplayerStatusButton? = multiplayerStatusButton
         set(button) {
             multiplayerStatusButton?.remove()
@@ -23,4 +24,8 @@ class StatusButtons(
         }
         addActor(nextTurnButton)
     }
+
+    override fun dispose() {
+        multiplayerStatusButton?.dispose()
+    }
 }