Null Pointer Exception after inflation?

Question

Below is my code for a fragment I have, I am trying to set the text of a textView in the view, I was under the impression that as long as you inflate the view first, it would not return null as it has been created. That according to the fragment life cycle.

 @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        View loginFragmentView = inflater.inflate(R.layout.login_layout, container, false);
        TextView imei = (TextView) loginFragmentView.findViewById(R.id.txt_device_id);
        imei.setText("IMEI: ");
        return loginFragmentView;
    }

This does cause the application to crash with the nullPointerException, does anyone know how to get around this. Is there a method I can override that will only be called one the fragment lifecycle has finished.

I also tried to put it in onResume() as that is right at the end of the lifecycle buthad same result. Any Idea?

EDIT

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:text="Your device ID:"
        android:id="@+id/txt_id_title"
        android:layout_marginTop="15dp"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceSmall"
        android:text="Fetching ID..."
        android:id="@+id/txt_device_id"
        android:layout_below="@+id/txt_id_title"
        android:layout_centerHorizontal="true" />
</RelativeLayout>

ERROR LOG

05-22 19:40:02.230 2799-2799/? E/AndroidRuntime: FATAL EXCEPTION: main
                                                 Process: alertssystem.rrr.lsa13.rrr_alerts, PID: 2799
                                                 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.widget.TextView.toString()' on a null object reference
                                                     at alertssystem.rrr.lsa13.rrr_alerts.login_layout_fragment.onCreateView(login_layout_fragment.java:24)
                                                     at android.app.Fragment.performCreateView(Fragment.java:2053)
                                                     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:894)
                                                     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067)
                                                     at android.app.BackStackRecord.run(BackStackRecord.java:833)
                                                     at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1452)
                                                     at android.app.FragmentManagerImpl$1.run(FragmentManager.java:447)
                                                     at android.os.Handler.handleCallback(Handler.java:739)
                                                     at android.os.Handler.dispatchMessage(Handler.java:95)
                                                     at android.os.Looper.loop(Looper.java:135)
                                                     at android.app.ActivityThread.main(ActivityThread.java:5221)
                                                     at java.lang.reflect.Method.invoke(Native Method)
                                                     at java.lang.reflect.Method.invoke(Method.java:372)
                                                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
                                                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

Make sure there is a `TextView` with the id `txt_device_id` in the `login_layout` layout. — Titus, May 22 '16 at 11:50

score 0 · Accepted Answer · answered May 22 '16 at 11:59

0

Your problem is because you are declaring the TextView too early according to the fragment lifycycle, so, instead of declaring it at onCreateView, declare it at onViewCreated, so it will be:

 @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        View loginFragmentView = inflater.inflate(R.layout.login_layout, container, false);
        return loginFragmentView;
    }


  @Override
  public void onViewCreated(View loginFragmentView, Bundle savedInstanceState) {
      super.onViewCreated(view, savedInstanceState);

      TextView imei = (TextView) loginFragmentView.findViewById(R.id.txt_device_id);
      imei.setText("IMEI: ");
  }

answered May 22 '16 at 11:59

Muhammed Refaat

8,914
14
83
118

Still returns a null pointer. :( Exactly same as above. – Luke Swain May 22 '16 at 12:06
the TextView name is `txt_id_title` not `txt_device_id` – Muhammed Refaat May 22 '16 at 12:12
Look under it, don't get confused with the android:layout_below bit, – Luke Swain May 22 '16 at 12:15
So, make sure what layout you are running this at, if you are providing more than layout according to width like `layout-sw600dp` may be you are not providing this TextView inside this layout. – Muhammed Refaat May 22 '16 at 12:18
I'm sorry, no idea what you mean. – Luke Swain May 22 '16 at 12:20
how many `loginFragmentView` you have ?!! only one in layouts folder?!! or you have a lot of it according to layout width ? – Muhammed Refaat May 22 '16 at 12:21
1

WOW! OMG I am blind. – Luke Swain May 22 '16 at 12:26
I was doing this code in LoginFragment java file and xml was in register. So the code was not taking place, as register was not created yet from login. :/ – Luke Swain May 22 '16 at 12:26
great, I'm happy I could help in solving your problem :), you have to watch for that in the future – Muhammed Refaat May 22 '16 at 12:27

score 0 · Answer 2 · answered May 22 '16 at 12:05

0

Looking at your stacktrace I guess your loginFragmentView doesn't have child of type textview with id txt_device_id so check if in inflate method you are passing correct layout name which contains textview with id you are trying to find

answered May 22 '16 at 12:05

Chirag Jain

133
9

It is definitely in there. see layout markup in question. – Luke Swain May 22 '16 at 12:08
you can check whether your loginViewFragment contains that view or not by putting break point at TextView imei = (TextView) loginFragmentView.findViewById(R.id.txt_device_id); and evaluate expression. check the childs of loginViewFragment – Chirag Jain May 22 '16 at 12:13

Null Pointer Exception after inflation?

2 Answers2