java.lang.ClassNotFoundException when install app from APK [duplicate]

Question

This question already has an answer here:

• Android ClassNotFoundException: Didn't find class on path 36 answers

The error I describe below, occurs when:

• Install the app on a device directly from the APK.
• Download the app by Play Store

The error don´t occurs when:

• Install apk through Eclipse pressing the 'run' button

    java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{my.package/my.package.MainActivity}:

java.lang.ClassNotFoundException: my.package.MainActivity

at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1998)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2099)
at android.app.ActivityThread.access$600(ActivityThread.java:138)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4929)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:798)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:565)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException: my.package.MainActivity
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
at android.app.Instrumentation.newActivity(Instrumentation.java:1056)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1989)
... 11 more

To export the APk I do as always, from "Use the Export Wizard to export and sign an APK"

Any idea because it occurs from the APK but not directly from eclipse?

The above error is generated by me. But reports of users are somewhat different:

User1:

java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{my.package/my.package.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "my.package.MainActivity" on path: DexPathList[dexElements=[zip file "/data/app/my.package-1.apk"],nativeLibraryDirectories=[/data/app-lib/my.package-1, /vendor/lib, /system/lib]]

User2:

java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{my.package/my.package.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "my.package.MainActivity" on path: DexPathList[[zip file "/data/app/my.package-1.apk"],nativeLibraryDirectories=[/data/app-lib/my.package-1, /vendor/lib, /system/lib]]

Manifest:

<?xml version="1.0" encoding="utf-8"?> <manifest
xmlns:android="http://schemas.android.com/apk/res/android"
package="my.package"
android:versionCode="12"
android:versionName="2.3" >

<uses-sdk
    android:minSdkVersion="9"
    android:targetSdkVersion="21" />

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


    <activity
        android:name="my.package.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>
     <activity android:name="my.package.AlarmsListActivity" 
               android:theme="@style/dialogTheme"/>
     <activity android:name="my.package.ImagenesActivity"/>         
     <activity android:name="my.package.EndActivity" />  


</application>

</manifest>

I use the following libraries in MainActivity

Answer 1

This is your error:

java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{my.package/my.package.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "my.package.MainActivity" on path: DexPathList[dexElements=[zip file "/data/app/my.package-1.apk"],nativeLibraryDirectories=[/data/app-lib/my.package-1, /vendor/lib, /system/lib]]

Solution:

You have added library project as a reference to your project and also may be you have added jar files for ChartView and support-v7 in your libs folder and also as a Add External Jars. So you have to enable both checkboxes for android-support-v7.jar file and for chartview jar file in order and export menu.

The path for it is,

Project - Right Click - Properties - Java Build Path - Order and Export Menu.

Finally you need to clean and run your project.