К сожалению, ваше приложение перестало работать - android

Question

Вот ловушка. Пожалуйста, помогите

04-30 11:52:45.716: E/AndroidRuntime(1430): FATAL EXCEPTION: main 
04-30 11:52:45.716: E/AndroidRuntime(1430): java.lang.RuntimeException: Unable to start activity ComponentInfo{my.calc/my.calc.CalcActivity}: java.lang.NullPointerException 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.ActivityThread.access$600(ActivityThread.java:123) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.os.Handler.dispatchMessage(Handler.java:99) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.os.Looper.loop(Looper.java:137) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.ActivityThread.main(ActivityThread.java:4424) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at java.lang.reflect.Method.invokeNative(Native Method) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at java.lang.reflect.Method.invoke(Method.java:511) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at dalvik.system.NativeStart.main(Native Method) 
04-30 11:52:45.716: E/AndroidRuntime(1430): Caused by: java.lang.NullPointerException 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at my.calc.CalcActivity.onCreate(CalcActivity.java:47) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.Activity.performCreate(Activity.java:4465) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 
04-30 11:52:45.716: E/AndroidRuntime(1430):  ... 11 more 
04-30 11:53:59.415: E/AndroidRuntime(1445): FATAL EXCEPTION: main 
04-30 11:53:59.415: E/AndroidRuntime(1445): java.lang.RuntimeException: Unable to start activity ComponentInfo{my.calc/my.calc.CalcActivity}: java.lang.NullPointerException 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.ActivityThread.access$600(ActivityThread.java:123) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.os.Handler.dispatchMessage(Handler.java:99) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.os.Looper.loop(Looper.java:137) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.ActivityThread.main(ActivityThread.java:4424) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at java.lang.reflect.Method.invokeNative(Native Method) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at java.lang.reflect.Method.invoke(Method.java:511) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at dalvik.system.NativeStart.main(Native Method) 
04-30 11:53:59.415: E/AndroidRuntime(1445): Caused by: java.lang.NullPointerException 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at my.calc.CalcActivity.onCreate(CalcActivity.java:47) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.Activity.performCreate(Activity.java:4465) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 
04-30 11:53:59.415: E/AndroidRuntime(1445):  ... 11 more 

Answer 1

Ваше сообщение об ошибке говорит «NullPointerException», и это, кажется, было вызвано чем-то внутри onCreate() метода CalcActivity. Перейти к строке 47 вашего кода для этого класса, как показано:

04-30 11:53:59.415: E/AndroidRuntime(1445): Caused by: java.lang.NullPointerException 
04-30 11:53:59.415: E/AndroidRuntime(1445):  at my.calc.CalcActivity.onCreate(CalcActivity.java:47) 

Убедитесь, что вы не сделали вызов на объект, который не был инициализирован еще, или что в основном имеет значение null. Например,

List<String> strings; 
strings.get(0); // you should have done something like this one first: 
       // strings = new ArrayList<String>();