为什么在通过Eclipse添加JAR后在Android上获得NoClassDefFoundError？

Question

我想在我的Android应用程序中包含ZXing.

由于ZXing只提供java源代码,我自己创建了jar文件.

接下来,我通过将JAR拖动到Eclipse中我的Android项目的libs文件夹中添加了JAR.

项目资源管理器看起来像这样

构建路径如下所示

在我自己的代码中,我尝试从该JAR实例化一个类:

IntentIntegratorV30 integrator = new IntentIntegratorV30(this);

编译时没有错误.

但是我在运行时在真实设备上遇到以下错误:

06-09 21:06:32.050: E/AndroidRuntime(1656): java.lang.NoClassDefFoundError: com.google.zxing.integration.android.IntentIntegratorV30

完整的LogCat是:

06-09 21:06:32.010: I/ApplicationPackageManager(1656): cscCountry is not German : XEO
06-09 21:06:32.010: I/dalvikvm(1656): Could not find method com.google.zxing.integration.android.IntentIntegratorV30.parseActivityResult, referenced from method de.fzi.guideme.fragments.scanner.ScannerFragment.onActivityResult
06-09 21:06:32.010: W/dalvikvm(1656): VFY: unable to resolve static method 181: Lcom/google/zxing/integration/android/IntentIntegratorV30;.parseActivityResult (IILandroid/content/Intent;)Lcom/google/zxing/integration/android/IntentResult;
06-09 21:06:32.010: D/dalvikvm(1656): VFY: replacing opcode 0x71 at 0x0003
06-09 21:06:32.020: E/dalvikvm(1656): Could not find class 'com.google.zxing.integration.android.IntentIntegratorV30', referenced from method de.fzi.guideme.fragments.scanner.ScannerFragment.onCreateView
06-09 21:06:32.020: W/dalvikvm(1656): VFY: unable to resolve new-instance 67 (Lcom/google/zxing/integration/android/IntentIntegratorV30;) in Lde/fzi/guideme/fragments/scanner/ScannerFragment;
06-09 21:06:32.020: D/dalvikvm(1656): VFY: replacing opcode 0x22 at 0x002d
06-09 21:06:32.020: I/GuideMe(1656): Fragment: class de.fzi.guideme.fragments.scanner.ScannerFragment, manual: null, function: null, step: null
06-09 21:06:32.040: D/AndroidRuntime(1656): Shutting down VM
06-09 21:06:32.040: W/dalvikvm(1656): threadid=1: thread exiting with uncaught exception (group=0x401d2760)
06-09 21:06:32.050: E/AndroidRuntime(1656): FATAL EXCEPTION: main
06-09 21:06:32.050: E/AndroidRuntime(1656): java.lang.NoClassDefFoundError: com.google.zxing.integration.android.IntentIntegratorV30
06-09 21:06:32.050: E/AndroidRuntime(1656):     at de.fzi.guideme.fragments.scanner.ScannerFragment.onCreateView(ScannerFragment.java:47)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:735)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:926)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:909)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.FragmentManagerImpl.dispatchStart(FragmentManager.java:1584)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.Activity.performStart(Activity.java:4377)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1724)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1767)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.ActivityThread.access$1500(ActivityThread.java:122)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1005)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.os.Looper.loop(Looper.java:132)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at android.app.ActivityThread.main(ActivityThread.java:4028)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at java.lang.reflect.Method.invokeNative(Native Method)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at java.lang.reflect.Method.invoke(Method.java:491)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:844)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
06-09 21:06:32.050: E/AndroidRuntime(1656):     at dalvik.system.NativeStart.main(Native Method)

我使用Eclipse 3.7.2和Android SDK Tools Rev. 19以及运行Android 3.1的Samsung Galaxy Tab 10.1.

看起来JAR没有被包含在APK文件中.有关如何解决此问题的任何建议？

编辑:回答我自己的问题(作为评论中讨论的结果).我试图包含的JAR必须以某种方式出错.正确构建JAR将在别处讨论.

Answer 1

这昨天杀了我.我也没有错误构建,但运行错误.我认为它与Android SDK编译构建路径的方式有关.我终于重复了这些步骤并停止了错误:

1. 在Android项目的根目录中创建一个名为libs的文件夹.
2. 将jar添加到该文件夹​​.
3. 右键单击jar并单击以添加到构建路径.
4. 清理您的项目.
5. 建立项目.
6. 跑.

通过android无法从外部jar中找到类