Question

我有本地JSON和Web服务器。当我从Web服务器获取数据时，它可以在ListView中设置项目。但是当我从本地JSON获取数据时，它不起作用而不在ListView中设置项目。

这是从Web服务器获取的代码，它起作用：

public void work2(String url) {
    pDialog = new ProgressDialog(this);
    String dowspee = getResources().getString(R.string.dowspee);
    String load = getResources().getString(R.string.Loadingd);
    pDialog.setTitle(load);
    pDialog.setMessage(dowspee);
    pDialog.show();
    JsonArrayRequest movieReq = new JsonArrayRequest(url, new Response.Listener<JSONArray>() {
        @Override
        public void onResponse(JSONArray response) {

            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.setThumbnailUrl(obj.getString("image"));
                    movie.seturl(obj.getString("url"));
                    movie.setRating(((Number) obj.get("rating")).doubleValue());
                    movie.setYear(obj.getInt("releaseYear"));

                    movie.setStat(obj.getString("State"));
                    // 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);
                    JSONArray epArry = obj.getJSONArray("eps");
                    ArrayList<String> ep = new ArrayList<String>();
                    for (int j = 0; j < epArry.length(); j++) {
                        ep.add((String) epArry.get(j));
                    }
                    movie.setep(ep);
                    movieList.add(movie);
                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }
            adapter.notifyDataSetChanged();
        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            hidePDialog();
        }
    });
    AppController.getInstance().addToRequestQueue(movieReq);
    movieList.clear();
    listView = (ListView) findViewById(R.id.list);
    adapter = new CustomListAdapter(this, movieList);
    listView.setAdapter(adapter);

}

但是当我尝试从txt文件获取并放入ListView时，它不会在ListView中显示任何内容：

public void workhistory() {
    Movie movie = new Movie();
    try {

        JSONObject obj = new JSONObject(loadJSONFromAsset());
        movie.setTitle(obj.getString("title"));
        movie.setThumbnailUrl(obj.getString("image"));
        movie.seturl(obj.getString("url"));
        movie.setRating(((Number) obj.get("rating")).doubleValue());
        movie.setYear(obj.getInt("releaseYear"));
        movie.setStat(obj.getString("State"));
        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);
        JSONArray epArry = obj.getJSONArray("eps");
        ArrayList<String> ep = new ArrayList<String>();
        for (int j = 0; j < epArry.length(); j++) {
            ep.add((String) epArry.get(j));
        }
        movie.setep(ep);
        movieList.add(movie);
        adapter.notifyDataSetChanged();
    } catch (JSONException e) {
        e.printStackTrace();
    }

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

public String loadJSONFromAsset() {
    String json = null;
    try {

        InputStream is = new FileInputStream("/storage/emulated/0/data/1.json");
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        json = new String(buffer, "UTF-8");
    } catch (IOException ex) {
        ex.printStackTrace();
        return null;
    }
    System.out.println(json);
    return json;
}

这是JSON：

{
"genre": [
"Music",
"Sci-Fi"
],
"eps": [
"1",
"2",
"3",
"4",
"5",
"6",
"7",
"8",
"9",
"10",
"11",
"12",
"13"
],
"title": "AKB0048 First Stage",
"State": "Completed",
"image": ".jpg",
"rating": 7.68,
"url": "http:\/\/",
"releaseYear": 2012
}

Answer 1

我找到了解决方案：

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

我应该把它们放在：

之后

      adapter.notifyDataSetChanged();

感谢。

Android - 从JSON设置ListView中的项目

1 个答案: