NullPointerException in Opening Android Activity

Question

When I cast my elements from the other layout I got this error.

final  Spinner mainIng = (Spinner) findViewById(R.id.spinner);
final  EditText sub1 = (EditText) findViewById(R.id.sub1);
final  EditText sub2 = (EditText) findViewById(R.id.sub2);
final  EditText sub3 = (EditText) findViewById(R.id.sub3);
final  EditText sub4 = (EditText) findViewById(R.id.sub4);
final  EditText sub5 = (EditText) findViewById(R.id.sub5);
final  EditText sub6 = (EditText) findViewById(R.id.sub6);

heres my error

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.Window.findViewById(int)' on a null object reference

No it is located before my Activity was called. I want it to be a global variable. — Jellolicious, Mar 01 '16 at 16:10
There is a good amount of code missing from this snippet to answer the question accurately. Can you please post the entire class and method declaration if it's not too large. At least the whole method and which class it is contained in would be helpful. — Bobbake4, Mar 01 '16 at 16:14
Share your XML code as well and also tell if you are placing above mentioned code after setContentView ? — Salman Nazir, Mar 01 '16 at 16:19

score 1 · Answer 1 · edited May 23 '17 at 12:31

1

Are you calling this from onCreate()? If yes try moving it to onCreateView() and call it with the inflated view or call it even later.

If you do then findViewById won't work, because the window is not yet created.

findViewById() returns null when I call it in onCreate()

edited May 23 '17 at 12:31

Community

1
1

answered Mar 01 '16 at 16:11

Jan

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score 0 · Answer 2 · edited Mar 01 '16 at 16:24

0

You need to init views in onCreate():

public class YourActivity extends Activity {
Spinner mainIng; 

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.your_activity_xml);
    mainIng= (Spinner) findViewById(R.id.spinner);
}

edited Mar 01 '16 at 16:24

CaptJak

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answered Mar 01 '16 at 16:09

Leonid Veremchuk

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giannisf · Accepted Answer · 2016-03-01T16:15:42.593

0

Place your code after the setContentView in your activity.

if you want them to be available in every method of your activity, declare them as fields.

public class MyActivity extends Activity {
         Spinner mySpiner;


     @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.my_layout);

       mySpiner = (Spinner) findViewById(R.id.mySpiner);

and then instantiate them after.

edited Mar 01 '16 at 16:15

answered Mar 01 '16 at 16:10

giannisf

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Ok thank you so much sir :) – Jellolicious Mar 01 '16 at 16:11
@Jellolicious please accept answer if helped you. Thanks – giannisf Mar 01 '16 at 16:16

NullPointerException in Opening Android Activity

3 Answers3