에러 메세지 질문입니다.

Question

E/AndroidRuntime: FATAL EXCEPTION: main
                  Process: com.example.ksw.lockscreenview, PID: 955
                  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.ksw.lockscreenview/com.example.ksw.lockscreenview.MainActivity}: java.lang.NullPointerException
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
                      at android.app.ActivityThread.access$800(ActivityThread.java:135)
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
                      at android.os.Handler.dispatchMessage(Handler.java:102)
                      at android.os.Looper.loop(Looper.java:136)
                      at android.app.ActivityThread.main(ActivityThread.java:5001)
                      at java.lang.reflect.Method.invokeNative(Native Method)
                      at java.lang.reflect.Method.invoke(Method.java:515)
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
                      at dalvik.system.NativeStart.main(Native Method)

                   Caused by: java.lang.NullPointerException
                      at com.example.ksw.lockscreenview.Preference.PreferencesHelper.isFisrt(PreferencesHelper.java:35)
                      at com.example.ksw.lockscreenview.MainActivity.onCreate(MainActivity.java:27)
                      at android.app.Activity.performCreate(Activity.java:5231)
                      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
                      at android.app.ActivityThread.access$800(ActivityThread.java:135)
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
                      at android.os.Handler.dispatchMessage(Handler.java:102)
                      at android.os.Looper.loop(Looper.java:136)
                      at android.app.ActivityThread.main(ActivityThread.java:5001)
                      at java.lang.reflect.Method.invokeNative(Native Method)
                      at java.lang.reflect.Method.invoke(Method.java:515)
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
                      at dalvik.system.NativeStart.main(Native Method) 

 

에러메세지는 이러하고, 여기서 두번째 NullPointerException 부분의 코드는

public static boolean isFirst()
{
    return mPrefManager.getBoolean("is_first", true);
}

또한 저 getBoolean은

public boolean getBoolean(String paramString, boolean paramBoolean)
{
    return this.mPref.getBoolean(paramString, paramBoolean);
}

이렇게 구성되어있습니다.

Answer 1

mPrefManager가 널이네요

mPrefManager = new PrefManager(mContext); 가 빠진거 같은데요