Android Eclipse，我不能在电话上启动新项目

我有个问题。我做了一个新的android应用程序项目，就是简单的hello world，并尝试在我的手机4.3 android上运行它

我的应用程序。正在启动，它突然关闭，并显示应用程序已停止的消息

0个bug，0个错误我没有更改代码中的任何内容。 我认为，只有在logcat中才有问题

    10-29 21:58:07.226: W/dalvikvm(4954): Unable to resolve superclass ofLcom/example/psw2/MainActivity; (2)
10-29 21:58:07.226: W/dalvikvm(4954): Link of class 'Lcom/example/psw2/MainActivity;' failed
10-29 21:58:07.231: D/AndroidRuntime(4954): Shutting down VM
10-29 21:58:07.231: W/dalvikvm(4954): threadid=1: thread exiting with uncaught exception (group=0x41f0b700)
10-29 21:58:07.236: E/AndroidRuntime(4954): FATAL EXCEPTION: main
10-29 21:58:07.236: E/AndroidRuntime(4954): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.psw2/com.example.psw2.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.example.psw2.MainActivity" on path: /data/app/com.example.psw2-1.apk
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2219)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.ActivityThread.access$700(ActivityThread.java:159)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.os.Looper.loop(Looper.java:176)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.ActivityThread.main(ActivityThread.java:5419)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at java.lang.reflect.Method.invokeNative(Native Method)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at java.lang.reflect.Method.invoke(Method.java:525)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1046)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:862)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at dalvik.system.NativeStart.main(Native Method)
10-29 21:58:07.236: E/AndroidRuntime(4954): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.psw2.MainActivity" on path: /data/app/com.example.psw2-1.apk
10-29 21:58:07.236: E/AndroidRuntime(4954):     at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:64)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.Instrumentation.newActivity(Instrumentation.java:1078)
10-29 21:58:07.236: E/AndroidRuntime(4954):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2210)
10-29 21:58:07.236: E/AndroidRuntime(4954):     ... 11 more

好的，我明白了

我必须按顺序勾选并导出所有项目，然后它就会运行

---

感谢您的帮助

logcat特别提到它找不到MainActivity的超类-什么是超类？该活动的全称包括包？package com.example.psw2；导入android.support.v7.app.ActionBarActivity；导入android.os.Bundle；导入android.view.Menu；导入android.view.MenuItem；公共类MainActivity扩展了ActionBarActivity我不知道我是否很了解您，这是您想要的吗？听起来Eclipse生成APK时没有正确地包括v7支持库。仔细检查项目设置以确保包含该库，然后尝试重新启动Eclipse并执行clean+构建。