我试图运行我的应用程序,但它在到达onCreate()方法之前崩溃。我是新来的android和eclipse,所以我甚至不知道从哪里开始寻找错误。Eclipse错误:无法实例化活动
这就是错误消息形式的logcat:
11-22 21:06:59.787: WARN/dalvikvm(433): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): FATAL EXCEPTION: main
11-22 21:07:01.468: ERROR/AndroidRuntime(433): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.app/com.example.app.HelloActivity}: java.lang.NullPointerException
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.os.Handler.dispatchMessage(Handler.java:99)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.os.Looper.loop(Looper.java:123)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.ActivityThread.main(ActivityThread.java:4627)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at java.lang.reflect.Method.invokeNative(Native Method)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at java.lang.reflect.Method.invoke(Method.java:521)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at dalvik.system.NativeStart.main(Native Method)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): Caused by: java.lang.NullPointerException
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.content.ContextWrapper.getSharedPreferences(ContextWrapper.java:146)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at com.example.app.HelloActivity.<init>(HelloActivity.java:51)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at java.lang.Class.newInstanceImpl(Native Method)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at java.lang.Class.newInstance(Class.java:1429)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)
11-22 21:07:01.468: ERROR/AndroidRuntime(433): ... 11 more
嗯...你在第51行的HelloActivity中有一个空指针异常,所以我建议看看那里。 – MrZander
如果您仍然难以编辑您的问题以包含HelloActivity的代码。 – Krylez
是的,那一行实际告诉你的是异常的行号:at com.example.app.HelloActivity。(HelloActivity.java:51)表示第51行,某些内容为空。 –
Jack