小编Ger*_*ard的帖子

我收到了nullPointerException:

java.lang.RuntimeException: Unable to start activity ComponentInfo{---private---}: 
      java.lang.NullPointerException: Attempt to invoke virtual method 'android.support.v4.app.FragmentTransaction 
      android.support.v4.app.FragmentManager.beginTransaction()' on a null object reference
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.support.v4.app.FragmentTransaction 
      android.support.v4.app.FragmentManager.beginTransaction()' on a null object reference
            at com.zero. ??? .BoxFragment.newInstance(BoxFragment.java:59)
            at com.zero. ??? .MainActivity$SectionPagerAdapter.getItem(MainActivity.java:111)
            at com.zero. ??? .MainActivity.onCreate(MainActivity.java:58)
            at android.app.Activity.performCreate(Activity.java:5937)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144) …