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java - Attempt to invoke virtual method

I am trying to get some LinearLayoutsin my onCreateView but my App is crashing with the following message:

23430-23430/? W/System.err﹕ java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference

Here is the code:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_main, container, false);

    new Body().execute();

        card01 = (LinearLayout) getView().findViewById(R.id.card01);
        card02 = (LinearLayout) getView().findViewById(R.id.card02);
        card03 = (LinearLayout) getView().findViewById(R.id.card03);
        card04 = (LinearLayout) getView().findViewById(R.id.card04);
        card05 = (LinearLayout) getView().findViewById(R.id.card05);
        card06 = (LinearLayout) getView().findViewById(R.id.card06);


        card01.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(getActivity(), "Card Clicked", Toast.LENGTH_SHORT).show();
            }
        });

    return rootView;
}

This is a pure Fragment class. The Activity which calls this Fragment does not contain this Fragment. Am I doing it wrong? Should the Fragmentalways be within the Activity?

As requested the whole AsyncTask:

    // AsyncTask
    private class Body extends AsyncTask<Void, Void, Void> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();

            mProgressDialog = new ProgressDialog(getActivity());
            mProgressDialog.setTitle("Fetching your info");
            mProgressDialog.setMessage("Loading...");
            mProgressDialog.setIndeterminate(false);
            mProgressDialog.show();

        }

        @Override
        protected Void doInBackground(Void... params) {

            Document doc;

            try {
                // Connect to the web site
                doc = Jsoup.connect(url).get();

                // Using Elements to get the Meta data

                //Date of Event
                Elements dateElement = doc.select("span[class=date-display-single]");

                //Headline of Event
                Elements titleElement = doc.select("h2[property=schema:name]");

                //Description of Event
                Elements bodyElement = doc.select("div[class=field field-name-body field-type-text-with-summary field-label-hidden]");

                // get the dates
                date1 = dateElement.eq(0).text();
                date2 = dateElement.eq(1).text();
                date3 = dateElement.eq(2).text();
                date4 = dateElement.eq(3).text();
                date5 = dateElement.eq(4).text();
                date6 = dateElement.eq(5).text();

                // get headlines
                head1 = titleElement.eq(0).text();
                head2 = titleElement.eq(1).text();
                head3 = titleElement.eq(2).text();
                head4 = titleElement.eq(3).text();
                head5 = titleElement.eq(4).text();
                head6 = titleElement.eq(5).text();

                // get description
                body1 = bodyElement.eq(0).toString();
                body1 = Jsoup.parse(body1.replaceAll("<br />", "br2n")).toString();
                body1 = Jsoup.parse(body1.replaceAll("</p>", "p2n")).text();
                body1 = body1.replaceAll("br2n", "
");
                body1 = body1.replaceAll("p2n", "

");

                body2 = bodyElement.eq(1).toString();
                body2 = Jsoup.parse(body2.replaceAll("<br />", "br2n")).toString();
                body2 = Jsoup.parse(body2.replaceAll("</p>", "p2n")).text();
                body2 = body2.replaceAll("br2n", "
");
                body2 = body2.replaceAll("p2n", "

");

                body3 = bodyElement.eq(2).toString();
                body3 = Jsoup.parse(body3.replaceAll("<br />", "br2n")).toString();
                body3 = Jsoup.parse(body3.replaceAll("</p>", "p2n")).text();
                body3 = body3.replaceAll("br2n", "
");
                body3 = body3.replaceAll("p2n", "

");

                body4 = bodyElement.eq(3).toString();
                body4 = Jsoup.parse(body4.replaceAll("<br />", "br2n")).toString();
                body4 = Jsoup.parse(body4.replaceAll("</p>", "p2n")).text();
                body4 = body4.replaceAll("br2n", "
");
                body4 = body4.replaceAll("p2n", "

");

                body5 = bodyElement.eq(4).toString();
                body5 = Jsoup.parse(body5.replaceAll("<br />", "br2n")).toString();
                body5 = Jsoup.parse(body5.replaceAll("</p>", "p2n")).text();
                body5 = body5.replaceAll("br2n", "
");
                body5 = body5.replaceAll("p2n", "

");

                body6 = bodyElement.eq(5).toString();
                body6 = Jsoup.parse(body6.replaceAll("<br />", "br2n")).toString();
                body6 = Jsoup.parse(body6.replaceAll("</p>", "p2n")).text();
                body6 = body6.replaceAll("br2n", "
");
                body6 = body6.replaceAll("p2n", "

");

                //cut out the date in the headlines (13 characters) if the String has something to cut
                //Let's  hope the website stays like this
                if (head1.length() > 0) {
                    head1 = head1.substring(13);
                }
                if (head2.length() > 0) {
                    head2 = head2.substring(13);
                }
                if (head3.length() > 0) {
                    head3 = head3.substring(13);
                }
                if (head4.length() > 0) {
                    head4 = head4.substring(13);
                }
                if (head5.length() > 0) {
                    head5 = head5.substring(13);
                }
                if (head6.length() > 0) {
                    head6 = head6.substring(13);
                }

                //Get Event Labels
                AssetManager am = getActivity().getAssets();
                bwe = BitmapFactory.decodeStream(am.open("label/bwe.jpg"));
                commaklar = BitmapFactory.decodeStream(am.open("label/commaklar.jpg"));
//                musica = BitmapFactory.decodeStream(am.open("label/musica.jpg"));
                doualatag = BitmapFactory.decodeStream(am.open("label/doualatag.jpg"));
                synestesia = BitmapFactory.decodeStream(am.open("label/synestesia.jpg"));
                douala = BitmapFactory.decodeStream(am.open("label/douala.jpg"));
//                tanzen = BitmapFactory.decodeStream(am.open("label/tanzen.jpg"));
//                nacht = BitmapFactory.decodeStream(am.open("label/nacht.jpg"));
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            mProgressDialog.dismiss();

            try {

                RobotoTextView date_widget1 = (RobotoTextView) getActivity().findViewById(R.id.date01);
                date_widget1.setText(date1);

                RobotoTextView head_widget1 = (RobotoTextView) getActivity().findViewById(R.id.head01);
                head_widget1.setText(head1);

                RobotoTextView body_widget1 = (RobotoTextView) getActivity().findViewById(R.id.body1);
                Whitelist.simpleText().addTags("br", "p");
                body_widget1.setText(body1);

                ImageView label1 = (ImageView) getView().findViewById(R.id.label1);

                if (head1.contains("BLACKWHITE")) {
                    label1.setImageBitmap(bwe);
                }
                if (date1.contains("Do")) {
                    ;
                    label1.setImageBitmap(doualatag);
                }
                if (head1.contains("COMMAKLAR")) {
                    label1.setImageBitmap(commaklar);
                }
                if (head1.toLowerCase().contains("synestesia") | head1.contains("SYNESTESIA")) {
                    label1.setImageBitmap(synestesia);
                }
                if (label1.getDrawable() == null) {
                    label1.setImageBitmap(douala);
                }

                RobotoTextView date_widget2 = (RobotoTextView) getActivity().findViewById(R.id.date02);
                date_widget2.setText(date2);

                RobotoTextView head_widget2 = (RobotoTextView) getActivity().findViewById(R.id.head02);
                head_widget2.setText(head2);

                RobotoTextView body_widget2 = (RobotoTextView) getActivity().findViewById(R.id.body2);
                body_widget2.setText(body2);

                ImageView label2 = (ImageView) getView().findViewById(R.id.label2);

                if (head2.contains("BLACKWHITE")) {
                    label2.setImageBitmap(bwe);
                }
                if (date2.contains("Do")) {
                    label2.setImageBitmap(doualatag);
                }
                if (head2.contains("COMMAKLAR")) {
                    label2.setImageBitmap(commaklar);
                }
                if (head2.toLowerCase().contains("synestesia")) {
                    label2.setImageBitmap(synestesia);
                }
                if (label2.getDrawable() == null) {
                    label2.setImageBitmap(douala);
                }

                RobotoTextView date_widget3 = (RobotoTextView) getActivity().findViewById(R.id.date03);
                date_widget3.setText(date3);

                RobotoTextView head_widget3 = (RobotoTextView) getActivity().findViewById(R.id.head03);
                head_widget3.setText(head3);

                RobotoTextView body_widget3 = (RobotoTextView) getActivity().findViewById(R.id.body3);
                body_widget3.setText(body3);

                ImageView label3 = (ImageView) getView().findViewById(R.id.label3);

                if (head3.contains("BLACKWHITE")) {
                    label3.setImageBitmap(bwe);
                }
                if (date3.contains("Do")) {
                    label3.setImageBitmap(doualatag);
                }
                if (head3.contains("COMMAKLAR")) {
                    label3.setImageBitmap(commaklar);
                }
                if (head3.toLowerCase().contains("synestesia")) {
                    label3.setImageBitmap(synestesia);
                }
                if (label3.getDrawable() == null) {
                    label3.setImageBitmap(douala);
                }

                RobotoTextView date_widget4 = (RobotoTextView) getActivity().findViewById(R.id.date04);
                date_widget4.setText(date4);

                RobotoTextView head_widget4 = (RobotoTextView) getActivity().findViewById(R.id.head04);
                head_widget4.setText(head4);

                RobotoTextView body_widget4 = (RobotoTextView) getActivity().findViewById(R.id.body4);
                body_widget4.setText(body4);

                ImageView label4 = (ImageView) getView().findViewById(R.id.label4);

                if (head4.contains("BLACKWHITE")) {
                    label4.setImageBitmap(bwe);
                }
                if (date4.contains("Do")) {
                    label4.setImageBitmap(doualatag);
                }

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1 Answer

0 votes
by (71.8m points)

Change to

 card01 = (LinearLayout) rootView.findViewById(R.id.card01);
 card02 = (LinearLayout) rootView.findViewById(R.id.card02);
 card03 = (LinearLayout) rootView.findViewById(R.id.card03);
 card04 = (LinearLayout) rootView.findViewById(R.id.card04);
 card05 = (LinearLayout) rootView.findViewById(R.id.card05);
 card06 = (LinearLayout) rootView.findViewById(R.id.card06);

You inflate a layout. the views belong to the inflated layout. So use the view object to initialize views in onCreateView

Fragment is hosted by a Acitvity

You can use getView in onActivityCreated and initialize views

Initialize your TextView's also in onCreateView. Since Asynctask is a inner class you can update ui there

Declare

 RobotoTextView date_widget2;

as instance variable

Then in onCreateView

 date_widget2= (RobotoTextView) rootView.findViewById(R.id.date02);

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