Question

这是我的沙发数据库中的JSON对象： https://emamafinal.iriscouch.com/stadtrundgang/_design/nodes/_view/nodes

我发现这个教程完全符合我的需要： http://www.learn2crack.com/2013/11/listview-from-json-example.html

只有两个问题： - 我需要在我的片段中使用ListView，我无法调用＆＃34; MainActivity.this＆＃34;在onPreExeute（）方法中。 - 我遇到的第二个问题是我收到此错误： org.json.JSONException：没有行的值

以下是我的片段中的代码：

ListView list;
TextView name;
TextView comment;
TextView lat;
Button Btngetdata;

ArrayList<HashMap<String, String>> oslist = new ArrayList<HashMap<String, String>>();
//URL to get JSON Array
private static String url = "https://emamafinal.iriscouch.com/stadtrundgang/_design/nodes/_view/nodes";

//JSON Node Names
private static final String TAG_ROWS = "rows";
private static final String TAG_NAME = "name";
private static final String TAG_COMMENT = "comment";
private static final String TAG_LAT = "latitude";
JSONArray android = null;

View rootView;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    rootView = inflater.inflate(R.layout.list_layout, container,false);

    oslist = new ArrayList<HashMap<String, String>>();
    Btngetdata = (Button)rootView.findViewById(R.id.getdata);

    Btngetdata.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            new JSONParse().execute();
        }
    });

    return rootView;
}

private class JSONParse extends AsyncTask<String, String, JSONObject> {
    private ProgressDialog pDialog;
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        name = (TextView)rootView.findViewById(R.id.name);
        comment = (TextView)rootView.findViewById(R.id.comment);
        lat = (TextView)rootView.findViewById(R.id.lat);
        pDialog = new ProgressDialog(MainActivity.this);
        pDialog.setMessage("Getting Data ...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }
    @Override
    protected JSONObject doInBackground(String... args) {
        JSONParser jParser = new JSONParser();
        // Getting JSON from URL
        JSONObject json = jParser.getJSONFromUrl(url);
        return json;
    }
    @Override
    protected void onPostExecute(JSONObject json) {
        pDialog.dismiss();
        try {
            // Getting JSON Array from URL
            android = json.getJSONArray(TAG_ROWS);
            for(int i = 0; i < android.length(); i++){
                JSONObject c = android.getJSONObject(i);
                // Storing  JSON item in a Variable
                String name = c.getString(TAG_NAME);
                String comment = c.getString(TAG_COMMENT);
                String lat = c.getString(TAG_LAT);
                // Adding value HashMap key => value
                HashMap<String, String> map = new HashMap<String, String>();
                map.put(TAG_NAME, name);
                map.put(TAG_COMMENT, comment);
                map.put(TAG_LAT, lat);
                oslist.add(map);
                list=(ListView)rootView.findViewById(R.id.list);
                ListAdapter adapter = new SimpleAdapter(MainActivity.this, oslist,
                        R.layout.list_item,
                        new String[] { TAG_NAME,TAG_COMMENT, TAG_LAT }, new int[] {
                        R.id.name,R.id.comment, R.id.lat});
                list.setAdapter(adapter);
                list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                    @Override
                    public void onItemClick(AdapterView<?> parent, View view,
                                            int position, long id) {
                        Toast.makeText(MainActivity.this, "You Clicked at "+oslist.get(+position).get("name"), Toast.LENGTH_SHORT).show();
                    }
                });
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }
}

}

提前感谢任何提示。

Answer 1

您应该在此行中使用getActivity()而不是MainActivity.this：

ListAdapter adapter = new SimpleAdapter(MainActivity.this, oslist,
                        R.layout.list_item, ...

ListAdapter adapter = new SimpleAdapter(getActivity(), oslist,
                        R.layout.list_item, ....

更正：将所有MainActivity.this更改为getActivity()

Android从JSON中填充Fragment中的ListView

1 个答案: