与画廊活动

Question

伊夫问题也随之而来关于如何使活动画廊tutoria [Android的开发者] [1]

[1]：http://developer.android.com/guide/tutorials/views/hello-gallery.html，但我得到了一个错误：

02-12 17:54:06.221: ERROR/AndroidRuntime(1330): Uncaught handler: thread main exiting due to uncaught exception 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.addsensor.CameraMap/com.addsensor.CameraMap.GalleryCamera}: java.lang.NullPointerException 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2268) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2284) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.app.ActivityThread.access$1800(ActivityThread.java:112) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1692) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.os.Handler.dispatchMessage(Handler.java:99) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.os.Looper.loop(Looper.java:123) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.app.ActivityThread.main(ActivityThread.java:3948) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at java.lang.reflect.Method.invokeNative(Native Method) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at java.lang.reflect.Method.invoke(Method.java:521) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:782) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:540) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at dalvik.system.NativeStart.main(Native Method) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330): Caused by: java.lang.NullPointerException 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at com.addsensor.CameraMap.GalleryCamera.onCreate(GalleryCamera.java:20) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123) 
    02-12 17:54:06.301: ERROR/AndroidRuntime(1330):  at 

android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2231) 

我[1]

[1]：Android Hello, Gallery tutorial -- "R.styleable cannot be resolved"但我仍然收到错误。它是一个简单的活动，我不知道如何遵循。任何人都知道？¿或如何解决它？¿

感谢

Answer 1

您正在尝试使用引用为空（例如变量初始化，等..）在CameraMap.GalleryCamera,onCreate()方法，行20

请寄出此方法的代码（并注明行号20）。