Android에서 UniWebView가 NoClassDefFoundError로 동작하지 않는 문제

2021-123 minunityuniwebviewandroidnoclassdeffounderrorkotlin

Android 빌드에서 UniWebView로 웹뷰 팝업을 띄우면 아래 예외가 발생하며 웹뷰가 동작하지 않았다.

AndroidJavaException: java.lang.NoClassDefFoundError: Failed resolution of: Lcom/onevcat/uniwebview/UniWebViewInterface$Companion$prepare$1;
java.lang.NoClassDefFoundError: Failed resolution of: Lcom/onevcat/uniwebview/UniWebViewInterface$Companion$prepare$1;
com.onevcat.uniwebview.UniWebViewInterface$Companion.prepare(UniWebViewInterface.kt:18)
com.onevcat.uniwebview.UniWebViewInterface.prepare(Unknown Source:2)
com.unity3d.player.UnityPlayer.nativeRender(Native Method)
com.unity3d.player.UnityPlayer.access$300(Unknown Source:0)
com.unity3d.player.UnityPlayer$e$1.handleMessage(Unknown Source:95)
android.os.Handler.dispatchMessage(Handler.java:102)
android.os.Looper.loop(Looper.java:246)
com.unity3d.player.UnityPlayer$e.run(Unknown Source:20)
Caused by: java.lang.ClassNotFoundException: com.onevcat.uniwebview.UniWebViewInterface$Companion$prepare$1
... 8 more
UnityEngine.AndroidJNISafe.CheckException () (at <00000000000000000000000000000000>:0)
UnityEngine.AndroidJavaObject._CallStatic (System.String methodName, System.Object[] args) (at <00000000000000000000000000000000>:0)
UniWebView.Awake () (at <00000000000000000000000000000000>:0)
UnityEngine.Object.Instantiate[T] (T original) (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupSystem+<LoadPopups>d__27.MoveNext () (at <00000000000000000000000000000000>:0)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <00000000000000000000000000000000>:0)
Rethrow as TypeInitializationException: The type initializer for 'UniWebViewInterface' threw an exception.
UniWebView.Awake () (at <00000000000000000000000000000000>:0)
UnityEngine.Object.Instantiate[T] (T original) (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupSystem+<LoadPopups>d__27.MoveNext () (at <00000000000000000000000000000000>:0)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <00000000000000000000000000000000>:0)
UnityEngine.Object:Instantiate(T)
Game.UI.Popup.<LoadPopups>d__27:MoveNext()
UnityEngine.SetupCoroutine:InvokeMoveNext(IEnumerator, IntPtr)

AndroidJavaException: java.lang.NoClassDefFoundError: Failed resolution of: Lkotlin/jvm/internal/Intrinsics;
java.lang.NoClassDefFoundError: Failed resolution of: Lkotlin/jvm/internal/Intrinsics;
com.onevcat.uniwebview.UniWebViewInterface$Companion.hide(Unknown Source:2)
com.onevcat.uniwebview.UniWebViewInterface.hide(Unknown Source:7)
com.unity3d.player.UnityPlayer.nativeRender(Native Method)
com.unity3d.player.UnityPlayer.access$300(Unknown Source:0)
com.unity3d.player.UnityPlayer$e$1.handleMessage(Unknown Source:95)
android.os.Handler.dispatchMessage(Handler.java:102)
android.os.Looper.loop(Looper.java:246)
com.unity3d.player.UnityPlayer$e.run(Unknown Source:20)
Caused by: java.lang.ClassNotFoundException: kotlin.jvm.internal.Intrinsics
... 8 more
UnityEngine.AndroidJNISafe.CheckException () (at <00000000000000000000000000000000>:0)
UnityEngine.AndroidJNISafe.CallStaticBooleanMethod (System.IntPtr clazz, System.IntPtr methodID, UnityEngine.jvalue[] args) (at <00000000000000000000000000000000>:0)
UnityEngine.AndroidJavaObject._CallStatic[ReturnType] (System.String methodName, System.Object[] args) (at <00000000000000000000000000000000>:0)
UniWebViewInterface.Hide (System.String name, System.Boolean fade, System.Int32 edge, System.Single duration, System.String identifier) (at <00000000000000000000000000000000>:0)
UniWebView.Hide (System.Boolean fade, UniWebViewTransitionEdge edge, System.Single duration, System.Action completionHandler) (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupWebView.OnDisable () (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupSystem+<LoadPopups>d__27.MoveNext () (at <00000000000000000000000000000000>:0)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <00000000000000000000000000000000>:0)
Game.UI.Popup.<LoadPopups>d__27:MoveNext()
UnityEngine.SetupCoroutine:InvokeMoveNext(IEnumerator, IntPtr)

AndroidJavaException: java.lang.NoClassDefFoundError: Failed resolution of: Lkotlin/jvm/internal/Intrinsics;
java.lang.NoClassDefFoundError: Failed resolution of: Lkotlin/jvm/internal/Intrinsics;
com.onevcat.uniwebview.UniWebViewInterface$Companion.setFrame(Unknown Source:2)
com.onevcat.uniwebview.UniWebViewInterface.setFrame(Unknown Source:7)
com.unity3d.player.UnityPlayer.nativeRender(Native Method)
com.unity3d.player.UnityPlayer.access$300(Unknown Source:0)
com.unity3d.player.UnityPlayer$e$1.handleMessage(Unknown Source:95)
android.os.Handler.dispatchMessage(Handler.java:102)
android.os.Looper.loop(Looper.java:246)
com.unity3d.player.UnityPlayer$e.run(Unknown Source:20)
Caused by: java.lang.ClassNotFoundException: kotlin.jvm.internal.Intrinsics
... 8 more
UnityEngine.AndroidJNISafe.CheckException () (at <00000000000000000000000000000000>:0)
UnityEngine.AndroidJavaObject._CallStatic (System.String methodName, System.Object[] args) (at <00000000000000000000000000000000>:0)
UniWebViewInterface.SetFrame (System.String name, System.Int32 x, System.Int32 y, System.Int32 width, System.Int32 height) (at <00000000000000000000000000000000>:0)
UniWebView.UpdateFrame () (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupWebView.SetUI () (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupWebView.Initialize (System.String url, UnityEngine.Vector4 insets, System.Single timeout) (at <00000000000000000000000000000000>:0)
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupSystem+<LoadPopups>d__27.MoveNext () (at <00000000000000000000000000000000>:0)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <00000000000000000000000000000000>:0)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at <00000000000000000000000000000000>:0)
Game.UI.Popup.PopupSystem+<LoadPopups>d__27.MoveNext () (at <00000000000000000000000000000000>:0)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <00000000000000000000000000000000>:0)

의심 1: UniWebView 4의 버그

Android SDK API 30과 관련된 문제인지 의심했다. UniWebView 릴리스 노트에는 다음 항목이 있다.

4.10.1 (11 Nov, 2021)

Fix

An issue that UniWebViewSafeBrowsing.IsSafeBrowsingSupported may always return false wrongly when build against Android API 30 or above.

의심 2: 빌드 옵션 설정 누락

빌드 옵션에서 웹뷰 동작에 필요한 설정이 빠졌는지도 의심했다.

원인: Kotlin 표준 라이브러리 누락

예외의 Caused by가 원인을 가리킨다. kotlin.jvm.internal.Intrinsics는 Kotlin 표준 라이브러리의 클래스이고, UniWebViewInterface$Companion$prepare$1은 UniWebView의 Kotlin 코드가 만든 클래스다. 최종 APK에 Kotlin 표준 라이브러리가 들어가지 않아 UniWebView의 Android 코드가 클래스를 찾지 못한 것이다. 위 두 의심은 이 예외와 직접 관련이 없다.

UniWebView 문서에 따르면 Android 쪽은 두 패키지에 의존한다.

Kotlin 표준 라이브러리(org.jetbrains.kotlin:kotlin-stdlib-jdk7)
Android X Browser(androidx.browser:browser)

기본값으로는 UniWebView가 Gradle 파일을 보고 둘을 자동으로 추가한다. Unity Preferences의 UniWebView 항목에서 “Adds Kotlin”이 꺼져 있거나, 다른 패키지가 Kotlin을 넣는다고 보고 끈 경우 이 예외가 난다.

해결 방법

당시 기록에는 최종 조치가 남아 있지 않다. UniWebView 문서 기준으로는 다음 순서로 해결한다.

Unity Preferences의 UniWebView 항목에서 “Adds Kotlin”을 켠다. 직접 관리하는 Gradle 템플릿을 쓴다면 implementation 'org.jetbrains.kotlin:kotlin-stdlib-jdk7:<버전>'을 추가한다.
설정을 바꾼 뒤 Build Settings의 Clean Build로 다시 빌드한다. UniWebView 문서는 설정을 바꾼 뒤 거의 모든 경우 Clean Build가 필요하다고 안내한다.
반대로 빌드에서 Duplicate class kotlin... 에러가 나면 다른 패키지가 이미 Kotlin을 넣은 것이므로 “Adds Kotlin”을 끈다.

https://docs.uniwebview.com/guide/trouble-shooting.html