Android开发【12-28视频贴】请教各位大神，怎么解决这个问题。

问题补充
12-30 04:45:04.334: E/AndroidRuntime(780): FATAL EXCEPTION: main
12-30 04:45:04.334: E/AndroidRuntime(780): java.lang.NullPointerException
12-30 04:45:04.334: E/AndroidRuntime(780): at com.android.internal.os.LoggingPrintStream.println(LoggingPrintStream.java:298)
12-30 04:45:04.334: E/AndroidRuntime(780): at com.example.MyFirstApp.FirstActivity$1.onClick(FirstActivity.java:63)
12-30 04:45:04.334: E/AndroidRuntime(780): at android.view.View.performClick(View.java:4240)
12-30 04:45:04.334: E/AndroidRuntime(780): at android.view.View$PerformClick.run(View.java:17721)
12-30 04:45:04.334: E/AndroidRuntime(780): at android.os.Handler.handleCallback(Handler.java:730)
12-30 04:45:04.334: E/AndroidRuntime(780): at android.os.Handler.dispatchMessage(Handler.java:92)
12-30 04:45:04.334: E/AndroidRuntime(780): at android.os.Looper.loop(Looper.java:137)
12-30 04:45:04.334: E/AndroidRuntime(780): at android.app.ActivityThread.main(ActivityThread.java:5103)
12-30 04:45:04.334: E/AndroidRuntime(780): at java.lang.reflect.Method.invokeNative(Native Method)
12-30 04:45:04.334: E/AndroidRuntime(780): at java.lang.reflect.Method.invoke(Method.java:525)
12-30 04:45:04.334: E/AndroidRuntime(780): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
12-30 04:45:04.334: E/AndroidRuntime(780): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-30 04:45:04.334: E/AndroidRuntime(780): at dalvik.system.NativeStart.main(Native Method)