ClassCastException: BadgeIcon cannot be cast to ScalableIcon when updating tool window

[Sourish-Kanna]

What happened

I was working in Android Studio when this exception occurred. It seems related to getting Flutter SDK information and updating a tool window icon.

Version information

Android Studio Narwhal Feature Drop | 2025.1.2 • Flutter plugin io.flutter 87.0 • Dart plugin 251.27623.5

Error getting Flutter sdk information.

Exception

Unhandled exception in [Kernel@k00ct4vknd266d3sop6s, Rete(failFast=false, commands=capacity=2147483647,data=[onReceive], reteState=kotlinx.coroutines.flow.StateFlowImpl@2133814f, dbSource=ReteDbSource(reteState=kotlinx.coroutines.flow.StateFlowImpl@2133814f)), DbSourceContextElement(kernel Kernel@k00ct4vknd266d3sop6s), ComponentManager(ProjectImpl@1976372176), com.intellij.codeWithMe.ClientIdContextElementPrecursor@724b97e7, CoroutineName(com.intellij.openapi.wm.impl.ToolWindowManagerImpl), ModalityState.NON_MODAL, Dispatchers.EDT]

java.lang.ClassCastException: class io.flutter.toolwindow.ToolWindowBadgeUpdater$BadgeIcon cannot be cast to class com.intellij.openapi.util.ScalableIcon (io.flutter.toolwindow.ToolWindowBadgeUpdater$BadgeIcon is in unnamed module of loader com.intellij.ide.plugins.cl.PluginClassLoader @58c76e46; com.intellij.openapi.util.ScalableIcon is in unnamed module of loader com.intellij.util.lang.PathClassLoader @68837a77)
	at com.intellij.openapi.wm.impl.SquareStripeButton.updatePresentation(SquareStripeButton.kt:244)
	at com.intellij.toolWindow.ToolWindowPaneNewButtonManager$createStripeButton$1.updateIcon(ToolWindowPaneNewButtonManager.kt:203)
	at com.intellij.openapi.wm.impl.ToolWindowManagerImpl.toolWindowPropertyChanged(ToolWindowManagerImpl.kt:2355)
	at com.intellij.openapi.wm.impl.ToolWindowImpl.setIcon(ToolWindowImpl.kt:583)
	at io.flutter.toolwindow.ToolWindowBadgeUpdater.lambda$updateBadgedIcon$0(ToolWindowBadgeUpdater.java:39)
	at com.intellij.openapi.wm.impl.ToolWindowManagerImpl$invokeLater$1.invokeSuspend(ToolWindowManagerImpl.kt:1621)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:104)
	at com.intellij.openapi.application.impl.EdtCoroutineDispatcher$wrapWithLocking$2$1.run(EdtCoroutineDispatcher.kt:71)
	at com.intellij.openapi.application.WriteIntentReadAction.lambda$run$0(WriteIntentReadAction.java:24)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runWriteIntentReadAction$lambda$6(AnyThreadWriteThreadingSupport.kt:274)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runWithTemporaryThreadLocal(AnyThreadWriteThreadingSupport.kt:204)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runWriteIntentReadAction(AnyThreadWriteThreadingSupport.kt:274)
	at com.intellij.openapi.application.impl.AnyThreadWriteThreadingSupport.runWriteIntentReadAction(AnyThreadWriteThreadingSupport.kt:222)
	at com.intellij.openapi.application.impl.ApplicationImpl.runWriteIntentReadAction(ApplicationImpl.java:1009)
	at com.intellij.openapi.application.WriteIntentReadAction.compute(WriteIntentReadAction.java:55)
	at com.intellij.openapi.application.WriteIntentReadAction.run(WriteIntentReadAction.java:23)
	at com.intellij.openapi.application.impl.EdtCoroutineDispatcher$wrapWithLocking$$inlined$Runnable$2.run(Runnable.kt:15)
	at com.intellij.openapi.application.impl.DispatchedRunnable.run(DispatchedRunnable.kt:42)
	at com.intellij.openapi.application.TransactionGuardImpl.runWithWritingAllowed(TransactionGuardImpl.java:240)
	at com.intellij.openapi.application.TransactionGuardImpl.access$100(TransactionGuardImpl.java:25)
	at com.intellij.openapi.application.TransactionGuardImpl$2.run(TransactionGuardImpl.java:222)
	at com.intellij.openapi.application.impl.FlushQueue.runNextEvent(FlushQueue.java:117)
	at com.intellij.openapi.application.impl.FlushQueue.flushNow(FlushQueue.java:43)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(Unknown Source)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
	at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
	at java.base/java.security.AccessController.doPrivileged(Unknown Source)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.desktop/java.awt.EventQueue.dispatchEvent(Unknown Source)
	at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.kt:585)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.kt:482)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$12$lambda$11$lambda$10$lambda$9(IdeEventQueue.kt:307)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:864)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$12$lambda$11$lambda$10(IdeEventQueue.kt:306)
	at com.intellij.ide.IdeEventQueueKt.performActivity$lambda$3(IdeEventQueue.kt:958)
	at com.intellij.openapi.application.TransactionGuardImpl.performActivity(TransactionGuardImpl.java:109)
	at com.intellij.ide.IdeEventQueueKt.performActivity(IdeEventQueue.kt:958)
	at com.intellij.ide.IdeEventQueue.dispatchEvent$lambda$12(IdeEventQueue.kt:301)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.kt:341)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.run(Unknown Source)
	Suppressed: kotlinx.coroutines.internal.DiagnosticCoroutineContextException: [Kernel@k00ct4vknd266d3sop6s, Rete(failFast=false, commands=capacity=2147483647,data=[onReceive], reteState=kotlinx.coroutines.flow.StateFlowImpl@2133814f, dbSource=ReteDbSource(reteState=kotlinx.coroutines.flow.StateFlowImpl@2133814f)), DbSourceContextElement(kernel Kernel@k00ct4vknd266d3sop6s), ComponentManager(ProjectImpl@1976372176), com.intellij.codeWithMe.ClientIdContextElementPrecursor@724b97e7, CoroutineName(com.intellij.openapi.wm.impl.ToolWindowManagerImpl), ModalityState.NON_MODAL, StandaloneCoroutine{Cancelled}@303d2547, Dispatchers.EDT]

[pq]

It looks like while the ToolWindow API only requires an Icon the ToolWindowManagerImpl is doing a cast to a ScalableIcon. The fix seems to be to make our BadgeIcon implement ScalableIcon. Will dig a little deeper.

[pq]

This is hitting a lot of folks so bumping in priority.