启动应用程序时在Android上找不到类异常

Question

In my app i have extended Application class and it was working, but now when i install it in another phone mine has lollipop and the one crashing has kitkat this error appears:

-18 13:26:20.604  16622-16622/? D/dalvikvm﹕ open_cached_dex_file : /data/app/cu.otsenre.tacodependiente-1.apk /data/dalvik-cache/data@app@cu.otsenre.tacodependiente-1.apk@classes.dex
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at org.acra.ACRA.init(ACRA.java:178)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at org.acra.ACRA.init(ACRA.java:136)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at org.acra.ACRA.init(ACRA.java:121)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at cu.otsenre.tacodependiente.utils.MySession.onCreate(MySession.java:46)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1007)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4541)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at android.app.ActivityThread.access$1500(ActivityThread.java:151)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1381)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at android.os.Handler.dispatchMessage(Handler.java:110)
08-18 13:26:20.826  16622-16622/? W/System.err﹕ at android.os.Looper.loop(Looper.java:193)
08-18 13:26:20.827  16622-16622/? W/System.err﹕ at android.app.ActivityThread.main(ActivityThread.java:5299)
08-18 13:26:20.827  16622-16622/? W/System.err﹕ at java.lang.reflect.Method.invokeNative(Native Method)
08-18 13:26:20.827  16622-16622/? W/System.err﹕ at java.lang.reflect.Method.invoke(Method.java:515)
08-18 13:26:20.827  16622-16622/? W/System.err﹕ at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:829)
08-18 13:26:20.827  16622-16622/? W/System.err﹕ at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:645)
08-18 13:26:20.827  16622-16622/? W/System.err﹕ at dalvik.system.NativeStart.main(Native Method)
08-18 13:26:20.827  16622-16622/? W/dalvikvm﹕ threadid=1: calling UncaughtExceptionHandler
08-18 13:26:20.828  16622-16622/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: cu.otsenre.tacodependiente, PID: 16622
    java.lang.NoClassDefFoundError: org.acra.ErrorReporter$1
            at org.acra.ErrorReporter.<clinit>(ErrorReporter.java:110)
            at org.acra.ACRA.init(ACRA.java:178)
            at org.acra.ACRA.init(ACRA.java:136)
            at org.acra.ACRA.init(ACRA.java:121)
            at cu.otsenre.tacodependiente.utils.MySession.onCreate(MySession.java:46)
            at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1007)
            at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4541)
            at android.app.ActivityThread.access$1500(ActivityThread.java:151)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1381)
            at android.os.Handler.dispatchMessage(Handler.java:110)
            at android.os.Looper.loop(Looper.java:193)
            at android.app.ActivityThread.main(ActivityThread.java:5299)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:829)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:645)
            at dalvik.system.NativeStart.main(Native Method)
08-18 13:26:20.884  16622-16622/? I/Process﹕ Sending signal. PID: 16622 SIG: 9

Can somebody help me, i have reinstalled android studio. clean project. don't know what else to do.

Answer 1

The most common mistake I have done when I get NoClassDefFoundError s is that my proguard configuration is obfuscating the class names.

See this page for more information about it: https://github.com/ACRA/acra/wiki/ProGuard especially:

# Keep all the ACRA classes
-keep class org.acra.** { *; }

Answer 2

Thanks for all your input, after some help from a friend i found that the problem was i had in my app build.gradle the instruction MultiDexEnable= true that was causing my app to work well in lollipop but gave that error in kitkat. I removed it and it worked like a charm. I honestly don't even know what that instruction was for but now my client can use my app. Thx for your help