Android：ClassNotFoundException類存在時

E/AndroidRuntime: FATAL EXCEPTION: main 
                 Process: be.kdg.examen, PID: 4451 
                 java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{be.kdg.examen/be.kdg.examen.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "be.kdg.examen.MainActivity" on path: DexPathList[[zip file "/data/app/be.kdg.examen-1/base.apk"],nativeLibraryDirectories=[/data/app/be.kdg.examen-1/lib/x86, /system/lib, /vendor/lib]] 
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2567) 
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
                  at android.app.ActivityThread.-wrap12(ActivityThread.java) 
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
                  at android.os.Handler.dispatchMessage(Handler.java:102) 
                  at android.os.Looper.loop(Looper.java:154) 
                  at android.app.ActivityThread.main(ActivityThread.java:6119) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 
                  Caused by: java.lang.ClassNotFoundException: Didn't find class "be.kdg.examen.MainActivity" on path: DexPathList[[zip file "/data/app/be.kdg.examen-1/base.apk"],nativeLibraryDirectories=[/data/app/be.kdg.examen-1/lib/x86, /system/lib, /vendor/lib]] 
                  at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56) 
                  at java.lang.ClassLoader.loadClass(ClassLoader.java:380) 
                  at java.lang.ClassLoader.loadClass(ClassLoader.java:312) 
                  at android.app.Instrumentation.newActivity(Instrumentation.java:1078) 
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2557) 
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)  
                  at android.app.ActivityThread.-wrap12(ActivityThread.java)  
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)  
                  at android.os.Handler.dispatchMessage(Handler.java:102)  
                  at android.os.Looper.loop(Looper.java:154)  
                  at android.app.ActivityThread.main(ActivityThread.java:6119)  
                  at java.lang.reflect.Method.invoke(Native Method)  
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)  
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

我試圖運行該應用程序時總是出現此錯誤。有一個MainActivity，所以我真的不知道問題是什麼。Android：ClassNotFoundException類存在時

來源

2017-08-14 sofboy

你必須包括multiDex在您的應用程序。

java.lang.ClassNotFoundException: Didn't find class "be.kdg.examen.MainActivity" on path: DexPathList[

將此添加到您的依賴項中。

compile 'com.android.support:multidex:1.0.1'

在你的Gradle中加入multiDexEnabled true。

android { 
    defaultConfig { 
     ... 
     minSdkVersion 21 
     targetSdkVersion 26 
     multiDexEnabled true // add this line 
    } 
    ... 
}

在你的清單中添加multiDex應用程序類。

<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="com.example.myapp"> 
    <application 
      android:name="android.support.multidex.MultiDexApplication" > 
     ... 
    </application> 
</manifest>

希望它能幫助:)

來源

2017-08-14 10:25:13

是由於這個工作！ – sofboy