在 Android Kotlin 协程中尝试/捕获导致崩溃

Question

In my android kotlin project, I want to run the following code:

CoroutineScope(Dispatchers.IO).launch {
   try
   {
      doStuff()
   }
   catch (exception: Exception)
   {
      exception.printStackTrace()
   }
}

For some reason, it looks like it works well if I compile and run that code using Android Studio 3.6.3, but not anymore with Android Studio 4, as I get the following error:

java.lang.VerifyError: Verifier rejected class com.myproject.DemoInteractor$connect$1: java.lang.Object com.myproject.DemoInteractor$connect$1.invokeSuspend(java.lang.Object) failed to verify: java.lang.Object com.myproject.DemoInteractor$connect$1.invokeSuspend(java.lang.Object): [0x95] register v3 has type Reference: java.lang.Throwable but expected Precise Reference: kotlin.jvm.internal.Ref$ObjectRef (declaration of 'com.myproject.DemoInteractor$connect$1' appears in /data/app/com.wezeejay.wezeejay-DjGgFSKkc9RkPSXWhfTUfQ==/base.apk:classes2.dex)

I figured out that when I remove the try/catch, like the following:

CoroutineScope(Dispatchers.IO).launch {
   doStuff()
}

it works.

How can I use the try/catch in my coroutine again?

Thanks.

Answer 1

Let me explain on this Coroutine have two methods- Async and launch. Launch doesn't return anything but Asynk return value.

If you need to use a try-catch in Coroutine Launch. Just modify you code and add async. However, by adding Asynk it will properly return the exception in your code.

CoroutineScope(Dispatchers.IO).launch {
     try {
            val deferred = async {
                codeThatCanThrowExceptions()
            }
            deferred.await()
        } catch(e: Exception) {
            // Exception thrown in async WILL NOT be caught here 
            // but propagated up to the scope
        }
}