Android Studio: ClassNotFoundException

Question

i was busy with my app for over a week, when suddenly:

11-12 07:59:17.860    1653-1653/nl.test.myapp E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.Runtim         


        

Answer 1

   try: 
   <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

Answer 2

https://stackoverflow.com/a/29821331/11480535 worked for me with the little addition that I also had to delete the projectFilesBackup/!

Answer 3

I had the same problem, turns out I screwed up with some final method. Be sure to check dalvikvm errors in logcat output before the FATAL EXCEPTION. I will give you some hints on the problem. In my case, I had a final method (isResumed) which was already defined in the base class - causing runtime crash. Wasn't complaining at compile time.

Check the logs:

E/dalvikvm( 9984): Method Lcom/your/package/ui/SomeActivity;.isResumed overrides final Landroid/app/Activity;.isResumed
W/dalvikvm( 9984): failed creating vtable
...
D/AndroidRuntime( 9962): Shutting down VM
...
E/AndroidRuntime(10065): FATAL EXCEPTION: main
E/AndroidRuntime(10065): Process: com.yourpackage.ui, PID: 10065
E/AndroidRuntime(10065): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.yourpackage.ui/com.yourpackage.ui.HomeActivity}: java.lang.ClassNotFoundException: Didn't find class "com.yourpackage.ui.HomeActivity" on path: DexPathList[[zip file "/data/app/com.yourpackage.ui-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.yourpackage.ui-2, /vendor/lib, /system/lib]]
...

Answer 4

You can check Multidex mechanism. The reason may be method numbers overflow.

1. Add MultiDex.install(this); to your Application:

   @Override
   protected void attachBaseContext(Context base) {
        super.attachBaseContext(base);
        MultiDex.install(this);
   }
   

2. and add

   afterEvaluate {
      tasks.matching {
          it.name.startsWith('dex')
      }.each { dx ->
          if (dx.additionalParameters == null) {
              dx.additionalParameters = []
          }
          dx.additionalParameters += '--multi-dex' // enable multidex
      }
   }
   

to your app module's gradle.build

Answer 5

i don't know this will help you..anyway try to use application theme as @style/Theme.AppCompat..we must use as per developers forum.

<application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/Theme.AppCompat" >

       <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>