NullPointerException in oncreateView() of Fragment

Question

This code below shows part of activity where the fragment is added.

---

    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    ft.replace(R.id.fragment_container, srkt_frag);
    ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
    ft.commit();

    TabSpec specs1=mTab.newTabSpec("tag1");
    specs1.setContent(R.id.fragment_container);
    specs1.setIndicator("SRK/T");
    mTab.addTab(specs1);

---

mTab is TabHost where the srkt_frag is displayed as the content. the fragment class is shown below

---

public class Srkt_x extends Fragment 
{
    @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            View view=inflater.inflate(R.layout.activity_srkt_x,container,false);
            TextView text = (TextView) getView().findViewById(R.id.srkt_power);
            Float result=getArguments().getFloat("RESULT");
            text.setText(String.valueOf(result));
            return view;

        }

}

---

after executing the project i get nullpointerexception at line 21 i.e at

TextView text = (TextView) getView().findViewById(R.id.srkt_power);

my xml file is shown below

---

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"

tools:context=".Srkt_x" >

<ScrollView
    android:id="@+id/srkt_scrollView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true"
    android:background="@color/Black" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="433dp" >

        <TextView
            android:id="@+id/srkt_power"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBottom="@+id/iolpower"
            android:layout_toRightOf="@+id/iolpower"
            android:clickable="false"
            android:ems="10"
            android:enabled="false"
            android:fadingEdge="horizontal"
            android:focusable="false"
            android:focusableInTouchMode="false"
            android:gravity="center|left"
            android:longClickable="false"
            android:paddingTop="10dp"
            android:textColor="@color/DeepSkyBlue"
            android:textSize="15sp" />

        <TextView
            android:id="@+id/iolpower"
            android:layout_width="100dp"
            android:layout_height="30dp"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true"
            android:layout_marginLeft="16dp"
            android:layout_marginTop="20dp"
            android:gravity="bottom|center"
            android:textColor="@color/White"
            android:inputType="text"
            android:text="@string/power"
            android:textSize="20sp"
            android:visibility="visible" />

        <TableLayout
            android:layout_width="228dp"
            android:layout_height="match_parent"
            android:layout_below="@+id/srkt_power"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="33dp"
            android:paddingTop="10dp" >

            <TableRow
                android:id="@+id/srkttableRow1"
                android:layout_height="wrap_content"
                android:background="@color/SkyBlue"
                android:orientation="vertical"
                android:showDividers="middle" >

                <TextView
                    android:id="@+id/iolCol"
                    android:layout_height="wrap_content"
                    android:layout_gravity="left"
                    android:layout_weight="1"
                    android:background="@color/SkyBlue"
                    android:gravity="center"
                    android:text="@string/iol"
                    android:textColor="@color/White"
                    android:textSize="20sp" />

                <TextView
                    android:id="@+id/refCol"
                    android:layout_height="wrap_content"
                    android:layout_gravity="right"
                    android:layout_weight="1"
                    android:background="@color/SkyBlue"
                    android:gravity="center"
                    android:text="@string/refr"
                    android:textColor="@color/White"
                    android:textSize="20sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow2"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd2"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref2"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow3"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd3"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref3"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow4"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd4"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref4"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow5"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd5"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref5"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow6"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd6"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref6"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow7"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd7"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:background="@color/DeepSkyBlue"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref7"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:background="@color/DeepSkyBlue"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow8"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd8"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref8"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow9"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd9"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref9"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow10"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd10"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref10"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow11"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd11"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref11"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>

            <TableRow
                android:id="@+id/srkttableRow12"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@color/Black" >

                <TextView
                    android:id="@+id/srktrnd12"
                    android:layout_gravity="left|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />

                <TextView
                    android:id="@+id/srktref12"
                    android:layout_gravity="right|center"
                    android:layout_weight="1"
                    android:gravity="center"
                    android:textColor="@color/White"
                    android:textSize="15sp" />
            </TableRow>
        </TableLayout>

    </RelativeLayout>
</ScrollView>

---

the log file is shown below

---

   03-26 23:49:22.333: D/AndroidRuntime(497): Shutting down VM
03-26 23:49:22.333: W/dalvikvm(497): threadid=1: thread exiting with uncaught exception (group=0x40015560)
03-26 23:49:22.353: E/AndroidRuntime(497): FATAL EXCEPTION: main
03-26 23:49:22.353: E/AndroidRuntime(497): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.iolcalci/com.example.iolcalci.Menu}: java.lang.NullPointerException
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.os.Handler.dispatchMessage(Handler.java:99)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.os.Looper.loop(Looper.java:123)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.ActivityThread.main(ActivityThread.java:3683)
03-26 23:49:22.353: E/AndroidRuntime(497):  at java.lang.reflect.Method.invokeNative(Native Method)
03-26 23:49:22.353: E/AndroidRuntime(497):  at java.lang.reflect.Method.invoke(Method.java:507)
03-26 23:49:22.353: E/AndroidRuntime(497):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
03-26 23:49:22.353: E/AndroidRuntime(497):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
03-26 23:49:22.353: E/AndroidRuntime(497):  at dalvik.system.NativeStart.main(Native Method)
03-26 23:49:22.353: E/AndroidRuntime(497): Caused by: java.lang.NullPointerException
03-26 23:49:22.353: E/AndroidRuntime(497):  at com.example.iolcalci.Srkt_x.onCreateView(Srkt_x.java:21)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:551)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1129)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.Activity.performStart(Activity.java:3791)
03-26 23:49:22.353: E/AndroidRuntime(497):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1620)
03-26 23:49:22.353: E/AndroidRuntime(497):  ... 11 more

---

I am not able to figure out the problem .any solution?

EDIT : line 22:Float result=getArguments().getFloat("RESULT");

EDIT 2 : setting arguments as shown below:

IOLPower_srkt=Srkt();

                Bundle srkt_bundle=new Bundle();
                srkt_bundle.putFloat("RESULT", IOLPower_srkt);

                srkt_frag.setArguments(srkt_bundle);

---

here Srkt() returns float value check detailed code

---

IOLPower_srkt=Srkt();
            Bundle srkt_bundle=new Bundle();
            srkt_bundle.putFloat("RESULT", IOLPower_srkt);
            srkt_frag.setArguments(srkt_bundle);



            IOLPower_bink=Binkhorst();
            Bundle bink_bundle=new Bundle();
            bink_bundle.putFloat("RESULT", IOLPower_bink);
            bink_frag.setArguments(bink_bundle);


            IOLPower_srk2=Srk2();
            if((Math.ceil(IOLPower_srk2)-IOLPower_srk2)>0.5){
                srk2_rnd=(float) Math.floor(IOLPower_srk2);
            }else{
                srk2_rnd=(float) Math.ceil(IOLPower_srk2);
            }
            Bundle srk2_bundle=new Bundle();
            srk2_bundle.putFloat("RESULT", srk2_rnd);
            srk2_frag.setArguments(srk2_bundle);



            IOLPower_holl=Holladay();
            Bundle holl_bundle=new Bundle();
            holl_bundle.putFloat("RESULT", IOLPower_holl);
            holl_frag.setArguments(holl_bundle);

        }
            });

    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    ft.replace(R.id.fragment_container, srkt_frag);
    ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
    ft.commit();

    TabSpec specs1=mTab.newTabSpec("tag1");
    specs1.setContent(R.id.fragment_container);
    specs1.setIndicator("SRK/T");
    mTab.addTab(specs1);


    TabSpec specs2=mTab.newTabSpec("tag2");
    specs2.setContent(R.id.fragment_container);
    specs2.setIndicator("SRK II");
    mTab.addTab(specs2);


    TabSpec specs3=mTab.newTabSpec("tag3");
    specs3.setContent(R.id.fragment_container);
    specs3.setIndicator("HOLLADAY");
    mTab.addTab(specs3);


    TabSpec specs4=mTab.newTabSpec("tag4");
    specs4.setContent(R.id.fragment_container);
    specs4.setIndicator("BINKHORST");
    mTab.addTab(specs4);

---

Pecos

Answer 1

How to solve: the clue of your log is Caused by: java.lang.NullPointerException at com.example.iolcalci.Srkt_x.onCreateView(Srkt_x.java:21)

which says that there is a Null Pointer Exception at Srkt_x.java line 21 so go to line 21 and see which of the values is equal to null and throw the exception.

The problem with your code is with TextView text = (TextView) getView().findViewById(R.id.srkt_power); where getView() is null as it has not been created.

The right code is:

public class Srkt_x extends Fragment 
{
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view=inflater.inflate(R.layout.activity_srkt_x,container,false);

        // use view instead of getView()
        TextView text = (TextView) view.findViewById(R.id.srkt_power);
        if(getArguments() != null) {
            Float result=getArguments().getFloat("RESULT");
            text.setText(String.valueOf(result));
        } else {
            text.setText("result not included");
        }
        return view;

    }

}

you have to use the inflated view in order to get the wanted TextView by id.

At the end of onCreateView when the return view; is executed, getView() will return the view value instead of null.

---

As suggested in the Android documentation page for Fragment, see TitlesFragment and DetailsFragment, use something like the code below in order to set arguments

public static Srkt_x newInstance(Float result) {
    Srkt_x f = new Srkt_x ();

    // Supply index input as an argument.
    Bundle args = new Bundle();
    args.putFloat("RESULT", result);
    f.setArguments(args);

    return f;
}

Spectacular

see my modification at code, now you should see result not included in the textview until you fix the problem with the missing Arguments – Spectacular

In your posted code there isn't called setArguments method check out the android dev of how to use fragments search for setArguments/getArguments developer.android.com/reference/android/app/Fragment.html – Spectacular

Answer 2

Instead of getView() use the view that you just inflated, since the view is not returned yet you will get a NPE Maybe like this:

View view=inflater.inflate(R.layout.activity_srkt_x,container,false);
TextView text = (TextView) view.findViewById(R.id.srkt_power);

//*** do something***

return view;

Interdepartmental

sorry about that will do it from now on :) – Interdepartmental

No problem, just a little tip :) – Koontz

could you point out which line in your code is 22? you should post the whole code it would be easier for us. – Interdepartmental

can I see how are you setting your arguments?? can't see in the posted code. – Interdepartmental

try to set your arguments in newInstance constructor of fragment. Android suggests it this way. – Interdepartmental

Answer 3

Replace

TextView text = (TextView) getView().findViewById(R.id.srkt_power);

with

TextView text = (TextView) getActivity().findViewById(R.id.srkt_power);

Fistula

Answer 4

The reason for your bug and confusion is due to not understanding how the Android event loop works.

You are calling getView() at a time when the fragment does not yet have one. The fragment will only have a view after onCreateView finishes running. The point of onCreateView is "to have the fragment instantiate its user interface view".

You should do getActivity().findViewById.

Arnold

Answer 5

Try doing what you need to do inside the method onViewCreated(), which you should override. Don't forget to call super() on it.

Overbold