setAdapter gridview send context

Question

I have this piece of code (LINE 2) that is returning :

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.projecti_popularmovies/com.example.android.projecti_popularmovies.MainActivity}: java.lang.NullPointerException

My code is :

public class MainActivity extends AppCompatActivity {

public MovieFragment mMovieFragment;
public Context mContext;

@Override
protected void onCreate(Bundle savedInstanceState) {
    mContext = this;
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mMovieFragment = new MovieFragment();
    if(savedInstanceState == null){
        getSupportFragmentManager().beginTransaction()
                .add(R.id.container, mMovieFragment)
                .commit();
    }
    if(mMovieFragment.getArrayImages() == null){
        Log.v(null, "Array is empty");
    }
    GridView gridView = (GridView) findViewById(R.id.gridview);
    gridView.setAdapter(new ImageAdapter(this, mMovieFragment.getArrayImages()));

    gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                                int position, long id) {
            Toast.makeText(MainActivity.this, "" + position,
                    Toast.LENGTH_SHORT).show();
        }
    });
}

I have checked the getArrayImages before this and its not null, I also tried to send the activity by getActivity() and it cannot find the method getActivity().

the word this refers to this activity context

Here is my constructor for ImageAdapter class:

public ImageAdapter(Context context, String[] images) {

This is the code to populate the mArrayImages:

    private Void getMovieImagesFromJson(String movieJSONstr) throws JSONException {

        final String OWM_RESULTS = "results";
        final String OWM_POSTERPATH = "poster_path";

        JSONObject movieJson = new JSONObject(movieJSONstr);
        JSONArray movieArray = movieJson.getJSONArray(OWM_RESULTS);

        Log.v("SIZE MOVIE ARRAY: ", Integer.toString(movieArray.length()));

        for(int i = 0; i < movieArray.length(); i++) {
            JSONObject movieObj = movieArray.getJSONObject(i);
            mArrayImages[i] = movieObj.getString(OWM_POSTERPATH);
        }

        return null;
    }

Can you post the whole Activity class to show where exactly is your GridView code in Activity? — Sharjeel, Sep 23 '15 at 20:13

Skizo-ozᴉʞS ツ · Accepted Answer · 2015-09-23T19:50:08.777

0

Declare a GlobalVariable

public Context mContext;

In your OnCreate() do this :

mContext = this;

Then you can call setAdapter and your Context won't be null.

gridView.setAdapter(new ImageAdapter(mContext, mMovieFragment.getArrayImages()));

EDIT

Try to use MainActivity.this instead.

edited Sep 23 '15 at 19:50

answered Sep 23 '15 at 19:21

Skizo-ozᴉʞS ツ

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didn't fix my problem – Joao Pereira Sep 23 '15 at 19:29
Create a question and link me the link and I'll try to help you :) – Skizo-ozᴉʞS ツ Sep 23 '15 at 19:42
http://stackoverflow.com/questions/30724689/android-multichoice-spinner-with-searchview-functionality – Pratik Butani Sep 23 '15 at 19:46
what do you need to see more? If the activity was not created it woudnt show anything on screen – Joao Pereira Sep 23 '15 at 19:46
@JoaoPereira You have to use `YoiurActivity.this` – Pratik Butani Sep 23 '15 at 19:49
Can you post the `getArrayImages()`? – Skizo-ozᴉʞS ツ Sep 23 '15 at 19:55
So your code in your `onCreate` is what you have posted? – Skizo-ozᴉʞS ツ Sep 23 '15 at 19:56
I added the method to populate ArrayImages – Joao Pereira Sep 23 '15 at 20:09
mContext = this; goes under the setcontentview – Skizo-ozᴉʞS ツ Sep 24 '15 at 09:20
And your get method returns a string not a String[] – Skizo-ozᴉʞS ツ Sep 24 '15 at 09:21

score 0 · Answer 2 · answered Sep 23 '15 at 20:03

0

Instead of

MainActivity.this

use getApplicationContext()

answered Sep 23 '15 at 20:03

Cody Harness

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setAdapter gridview send context

2 Answers2

EDIT