Unity Google Play排行榜错误：java.lang.ClassNotFoundException

我正在用unity制作2D手机游戏。使用gpgs插件，在google play登录成功，但Social.ShowReadBoardUI不起作用。 我寻找了同样的解决方案，但我找不到哪里出了问题。。请帮帮我！ 日志：

09-02 20:00:52.288 1290-1290/？D/ViewRootImpl@f60ae3d[UnityPlayerPractivity]：ViewPostImeInputStage进程指针0
09-02 20:00:52.468 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerPractivity]：ViewPostImeInputStage进程指针1
09-02 20:00:52.472 1290-1340/? I/Unity：使用令牌客户端启动身份验证。
（文件名：/Users/builduser/buildslave/unity/build/artifacts/generated/common/runtime/DebugBindings.gen.cpp行：51）
09-02 20:00:52.487 1290-1340/? W/Unity:**[Play Games Plugin DLL]09/02/18 11:00:52+00:00错误：异常启动令牌请求：java.lang.ClassNotFoundException:com.google.Games.bridge.TokenFragment
（文件名：/Users/builduser/buildslave/unity/build/artifacts/generated/common/runtime/DebugBindings.gen.cpp行：51）
09-02 20:00:52.488 1290-1340/? W/Unity:**[Play Games Plugin DLL]09/02/18 11:00:52+00:00错误：UnityEngine.AndroidJavaException:java.lang.ClassNotFoundException:com.google.Games.bridge.TokenFragment
位于：0中的UnityEngine.AndroidJNISafe.CheckException（）[0x00091]处
位于：0中的UnityEngine.AndroidJNISafe.CallStaticObjectMethod（System.IntPtr clazz、System.IntPtr methodID、UnityEngine.jvalue[]args）[0x00011]
在UnityEngine.AndroidJavaObject.\u调用静态[ReturnType]（System.String方法名，System.Object[]参数）[0x002d6]中：0
在：0中的UnityEngine.AndroidJavaObject.CallStatic[ReturnType]（System.String methodName，System.Object[]args）[0x00001]处
位于：0中的UnityEngine.AndroidJavaObject.FindClass（System.String名称）[0x0001d]
在UnityEngine.AndroidJavaClass.\u AndroidJavaClass（System.String类名）[0x00012]中：0
在UnityEngi
09-02 20:01:27.450 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]：MSG_RESIZED_REPORT:frame=Rect（0,0-8001280）ci=Rect（0,0-0,0）vi=Rect（0,32-0,0）或=1
09-02 20:01:27.480 1428-13816/? D/WindowManager:finishDrawingWindow:Window{8595e9fd0 u0 com.HAE.Fillette/com.unity3d.player.UnityPlayerPractivity}mDrawState=DRAW\u挂起
09-02 20:01:27.520 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerPractivity]：消息窗口焦点已更改0
09-02 20:01:27.559 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerPractivity]：重新发布返回：oldFrame=[0,0][8001280]newFrame=[0,0][8001280]结果=0x3曲面={isValid=true-1693452288}曲面GenerationChanged=false
09-02 20:01:27.560 1428-13815/? D/WindowManager:finishDrawingWindow:Window{8595e9fd0 u0 com.HAE.Fillette/com.unity3d.player.UnityPlayerPractivity}mDrawState=已绘制
09-02 20:01:28.558 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerPractivity]：重新发布返回：oldFrame=[0,0][8001280]newFrame=[0,0][8001280]结果=0x3曲面={isValid=true-1693452288}曲面GenerationChanged=false
09-02 20:01:28.559 1428-10491/? D/WindowManager:finishDrawingWindow:Window{8595e9fd0 u0 com.HAE.Fillette/com.unity3d.player.UnityPlayerPractivity}mDrawState=已绘制

统一版本：2017.3.0f3 JDK:1.8.0 GPGS插件版本：0.9.50 资产/插件/安卓

09-02 20:00:52.288 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]: ViewPostImeInputStage processPointer 0
09-02 20:00:52.468 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]: ViewPostImeInputStage processPointer 1
09-02 20:00:52.472 1290-1340/? I/Unity: Starting Auth with token client.

    (Filename: /Users/builduser/buildslave/unity/build/artifacts/generated/common/runtime/DebugBindings.gen.cpp Line: 51)
09-02 20:00:52.487 1290-1340/? W/Unity: *** [Play Games Plugin DLL] 09/02/18 11:00:52 +00:00 ERROR: Exception launching token request: java.lang.ClassNotFoundException: com.google.games.bridge.TokenFragment

    (Filename: /Users/builduser/buildslave/unity/build/artifacts/generated/common/runtime/DebugBindings.gen.cpp Line: 51)
09-02 20:00:52.488 1290-1340/? W/Unity: *** [Play Games Plugin DLL] 09/02/18 11:00:52 +00:00 ERROR: UnityEngine.AndroidJavaException: java.lang.ClassNotFoundException: com.google.games.bridge.TokenFragment
      at UnityEngine.AndroidJNISafe.CheckException () [0x00091] in <874146cf7d2d43c890e7556e286193df>:0 
      at UnityEngine.AndroidJNISafe.CallStaticObjectMethod (System.IntPtr clazz, System.IntPtr methodID, UnityEngine.jvalue[] args) [0x00011] in <874146cf7d2d43c890e7556e286193df>:0 
      at UnityEngine.AndroidJavaObject._CallStatic[ReturnType] (System.String methodName, System.Object[] args) [0x002d6] in <874146cf7d2d43c890e7556e286193df>:0 
      at UnityEngine.AndroidJavaObject.CallStatic[ReturnType] (System.String methodName, System.Object[] args) [0x00001] in <874146cf7d2d43c890e7556e286193df>:0 
      at UnityEngine.AndroidJavaObject.FindClass (System.String name) [0x0001d] in <874146cf7d2d43c890e7556e286193df>:0 
      at UnityEngine.AndroidJavaClass._AndroidJavaClass (System.String className) [0x00012] in <874146cf7d2d43c890e7556e286193df>:0 
      at UnityEngi
09-02 20:01:27.450 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]: MSG_RESIZED_REPORT: frame=Rect(0, 0 - 800, 1280) ci=Rect(0, 0 - 0, 0) vi=Rect(0, 32 - 0, 0) or=1
09-02 20:01:27.480 1428-13816/? D/WindowManager: finishDrawingWindow: Window{8595e9fd0 u0 com.HAE.Fillette/com.unity3d.player.UnityPlayerActivity} mDrawState=DRAW_PENDING
09-02 20:01:27.520 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]: MSG_WINDOW_FOCUS_CHANGED 0
09-02 20:01:27.559 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]: Relayout returned: oldFrame=[0,0][800,1280] newFrame=[0,0][800,1280] result=0x3 surface={isValid=true -1693452288} surfaceGenerationChanged=false
09-02 20:01:27.560 1428-13815/? D/WindowManager: finishDrawingWindow: Window{8595e9fd0 u0 com.HAE.Fillette/com.unity3d.player.UnityPlayerActivity} mDrawState=HAS_DRAWN
09-02 20:01:28.558 1290-1290/? D/ViewRootImpl@f60ae3d[UnityPlayerActivity]: Relayout returned: oldFrame=[0,0][800,1280] newFrame=[0,0][800,1280] result=0x3 surface={isValid=true -1693452288} surfaceGenerationChanged=false
09-02 20:01:28.559 1428-10491/? D/WindowManager: finishDrawingWindow: Window{8595e9fd0 u0 com.HAE.Fillette/com.unity3d.player.UnityPlayerActivity} mDrawState=HAS_DRAWN