Question

我想访问＆＃34; area＆＃34;价值，在里面＆＃34;地址＆＃34;列表视图中的对象。请参阅json。

的图片

我想在列表视图中解析json数据，但我无法访问Address内的区域。我在使用此代码后获得null。

在图片中看到我将区域视为空。

我如何获得该区域？

listrow.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/list_row_selector"
    android:padding="8dp" >

    <!-- Thumbnail Image -->
    <com.android.volley.toolbox.NetworkImageView
        android:id="@+id/thumbnail"
        android:layout_width="120dp"
        android:layout_height="80dp"
        android:layout_alignParentLeft="true"
        android:layout_marginRight="8dp" />

    <!-- Restaurant name  -->
    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"

        android:layout_toRightOf="@+id/thumbnail"
        android:textSize="@dimen/title"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/area"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/name"

        android:layout_toRightOf="@+id/thumbnail"
        android:textSize="@dimen/rating" />

    <!-- Rating -->
    <TextView
        android:id="@+id/average_ratings"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/area"
        android:layout_toRightOf="@+id/thumbnail"

        android:textSize="@dimen/rating" />

    <TextView
        android:id="@+id/cuisine"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/average_ratings"

        android:layout_toRightOf="@+id/thumbnail"
        android:textSize="@dimen/rating" />

    <!-- Genre -->
   <!-- <TextView
        android:id="@+id/genre"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/rating"
        android:layout_marginTop="5dp"
        android:layout_toRightOf="@+id/thumbnail"
        android:textColor="@color/genre"
        android:textSize="@dimen/genre" />-->
<!--
    &lt;!&ndash; Release Year &ndash;&gt;
    <TextView
        android:id="@+id/releaseYear"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:textColor="@color/year"
        android:textSize="@dimen/year" />-->

</RelativeLayout>

主要活动

public class MainActivity extends Activity {
    // Log tag
    private static final String TAG = MainActivity.class.getSimpleName();
    private static final String url = "http://sewqusviwc.localtunnel.me/api/v1/restaurants?per_page=10&page=1&sort_col=average_ratings";
    // Movies json url
    //private static final String url = "http://api.androidhive.info/json/movies.json";
    private ProgressDialog pDialog;
    private List<Movie> movieList = new ArrayList<Movie>();
    private ListView listView;
    private CustomListAdapter adapter;

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

        listView = (ListView) findViewById(R.id.list);
        adapter = new CustomListAdapter(this, movieList);
        listView.setAdapter(adapter);

        pDialog = new ProgressDialog(this);
        // Showing progress dialog before making http request
        pDialog.setMessage("Loading...");
        pDialog.show();

        // changing action bar color
        getActionBar().setBackgroundDrawable(
                new ColorDrawable(Color.parseColor("#1b1b1b")));

        // Creating volley request obj
        JsonArrayRequest movieReq = new JsonArrayRequest(url,
                new Response.Listener<JSONArray>() {
                    @Override
                    public void onResponse(JSONArray response) {
                        Log.d(TAG, response.toString());
                        hidePDialog();

                        // Parsing json
                        for (int i = 0; i < response.length(); i++) {
                            try {

                                JSONObject obj = response.getJSONObject(i);
                                Movie movie = new Movie();
                                //movie.setTitle(obj.getString("title"));
                                movie.setName(obj.getString("name"));
                                //movie.setThumbnailUrl(obj.getString("image"));
                                movie.setThumbnailUrl(obj.getString("image_url"));
                                movie.setAverage_ratings(obj.getString("average_ratings"));
                                movie.setCuisine(obj.getString("cuisine"));
                                //movie.setYear(obj.getInt("releaseYear"));

                                // Genre is json array
                                /*JSONArray genreArry = obj.getJSONArray("genre");
                                ArrayList<String> genre = new ArrayList<String>();
                                for (int j = 0; j < genreArry.length(); j++) {
                                    genre.add((String) genreArry.get(j));
                                }
                                movie.setGenre(genre);*/

                                // adding movie to movies array
                                movieList.add(movie);

                            } catch (JSONException e) {
                                e.printStackTrace();
                            }

                        }

                        // notifying list adapter about data changes
                        // so that it renders the list view with updated data
                        adapter.notifyDataSetChanged();
                    }
                }, new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        VolleyLog.d(TAG, "Error: " + error.getMessage());
                        hidePDialog();

                    }
                });

        // Adding request to request queue
        AppController.getInstance().addToRequestQueue(movieReq);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        hidePDialog();
    }

    private void hidePDialog() {
        if (pDialog != null) {
            pDialog.dismiss();
            pDialog = null;
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

自定义列表适配器

public class CustomListAdapter extends BaseAdapter {
    private Activity activity;
    private LayoutInflater inflater;
    private List<Movie> movieItems;
    ImageLoader imageLoader = AppController.getInstance().getImageLoader();

    public CustomListAdapter(Activity activity, List<Movie> movieItems) {
        this.activity = activity;
        this.movieItems = movieItems;
    }

    @Override
    public int getCount() {
        return movieItems.size();
    }

    @Override
    public Object getItem(int location) {
        return movieItems.get(location);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        if (inflater == null)
            inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (convertView == null)
            convertView = inflater.inflate(R.layout.list_row, null);

        if (imageLoader == null)
            imageLoader = AppController.getInstance().getImageLoader();
        NetworkImageView thumbNail = (NetworkImageView) convertView
                .findViewById(R.id.thumbnail);
        TextView name = (TextView) convertView.findViewById(R.id.name);
        TextView average_ratings = (TextView) convertView.findViewById(R.id.average_ratings);
        TextView address=(TextView) convertView.findViewById(R.id.area);
        TextView cuisine =(TextView) convertView.findViewById(R.id.cuisine);
        //TextView genre = (TextView) convertView.findViewById(R.id.genre);
        //TextView year = (TextView) convertView.findViewById(R.id.releaseYear);

        // getting movie data for the row
        Movie m = movieItems.get(position);

        // thumbnail image
        thumbNail.setImageUrl(m.getThumbnailUrl(), imageLoader);

        // title
        name.setText(m.getName());

        // rating
        average_ratings.setText("Rating: " + String.valueOf(m.getAverage_ratings()));
        address.setText("Area: " + String.valueOf(m.getAddress()));
        cuisine.setText("Cusine: " + String.valueOf(m.getCuisine()));
        /*// genre
        String genreStr = "";
        for (String str : m.getGenre()) {
            genreStr += str + ", ";
        }
        genreStr = genreStr.length() > 0 ? genreStr.substring(0,
                genreStr.length() - 2) : genreStr;
        genre.setText(genreStr);

        // release year
        year.setText(String.valueOf(m.getYear()));*/

        return convertView;
    }

Movie.java

public class Movie {
    private String name, thumbnailUrl;
    //private int year;
    private String average_ratings,area,cuisine,address;
//  private ArrayList<String> genre;

    public Movie() {
    }

    public Movie(String name, String thumbnailUrl, String average_ratings,String area,String cuisine,String address
            ) {
        this.name = name;
        this.thumbnailUrl = thumbnailUrl;
        //this.year = year;
        this.average_ratings = average_ratings;
        this.area=area;
        this.cuisine=cuisine;
this.address=address;
        //this.genre = genre;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getThumbnailUrl() {
        return thumbnailUrl;
    }

    public void setThumbnailUrl(String thumbnailUrl) {
        this.thumbnailUrl = thumbnailUrl;
    }

    /*public int getYear() {
        return year;
    }*/

    /*public void setYear(int year) {
        this.year = year;
    }*/

    public String getAverage_ratings() {
        return average_ratings;
    }

    public void setAverage_ratings(String average_ratings) {
        this.average_ratings = average_ratings;
    }
    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getCuisine() {
        return cuisine;
    }

    public void setCuisine(String cuisine) {
        this.cuisine = cuisine;
    }
    /*public ArrayList<String> getGenre() {
        return genre;
    }

    public void setGenre(ArrayList<String> genre) {
        this.genre = genre;
    }
*/
}

Answer 1

创建地址模型类：

Address.java：

class Address {

    private String area;
    private String fullAddress;

    public void set(String are){this.area = area;}
    public void set(String are){this.fullAddress= fullAddress;}

    public String getArea(){return area;}
    public String getFullAddress(){return fullAddress;}

}

你应该在Movie Model类中有一个地址设置器和getter方法。解析只从主json中解决json对象，就像你必须解析主json对象中的其他对象一样。

Json Parsing：

                   // Parsing json
                    for (int i = 0; i < response.length(); i++) {
                        try {

                            JSONObject obj = response.getJSONObject(i);
                            Movie movie = new Movie();
                            //movie.setTitle(obj.getString("title"));
                            movie.setName(obj.getString("name"));
                            //movie.setThumbnailUrl(obj.getString("image"));
                            movie.setThumbnailUrl(obj.getString("image_url"));
                            movie.setAverage_ratings(obj.getString("average_ratings"));
                            movie.setCuisine(obj.getString("cuisine"));
                            //movie.setYear(obj.getInt("releaseYear"));
                           if(obj.has("address")){
                              JSONObject addressJsonObj = obj.getJSONObject("address");
                              Address address = new Address();
                              address.setArea(addressJsonObj.getString("area"));
                              address.setFullAddress(addressJsonObj.getString("full_address"));
                              movie.setAddress(address);
                            }

                           // adding movie to movies array
                            movieList.add(movie);

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    }

Answer 2

创建obj之后：

JSONObject adressObject = obj.getJSONObject("adress");
String area = adressObject.get("area").toString();

如何在android listview中访问JSON对象的值？

2 个答案: