如何从PHP中获取数据并在android listview中显示在FRAGMENT中？

Question

在onPostExecute()错误投掷：

构造SimpleAdapter（商品， 的ArrayList>，整型，字符串[]，INT []）是 未定义

的问题是在我的AsyncTaskonPostExecute() ：

@Override 
     protected void onPostExecute(Void result) { 
      super.onPostExecute(result); 
      ListAdapter adapter = new SimpleAdapter(Commodities.this, 
        matchFixtureList, R.layout.list_item, new String[] { 
          TAG_SCRIPT, TAG_BUYSELL, TAG_TRADESELL, TAG_TARGET, 
          TAG_STOPLOSS, TAG_STATUS }, new int[] { 
          R.id.Script, R.id.BuySell, R.id.TradeSell, 
          R.id.Target, R.id.StopLoss, R.id.Status }); 
      setListAdapter(adapter); 
     } 

我该如何解决这个错误？这里是整个类代码：

public class Commodities extends ListFragment { 

    private String URL_ITEMS = "http://ourvadodara.ddns.net/NeptuneFinsol/commodities_fetch.php"; 
    private static final String TAG_COMMODITIES = "commodities"; 
    private static final String TAG_DATE = "date"; 
    private static final String TAG_SCRIPT = "script"; 
    private static final String TAG_BUYSELL = "buysell"; 
    private static final String TAG_TRADESELL = "tradesell"; 
    private static final String TAG_TARGET = "target"; 
    private static final String TAG_STOPLOSS = "stoploss"; 
    private static final String TAG_STATUS = "status"; 


    JSONArray matchFixture = null; 
    ArrayList<HashMap<String, String>> matchFixtureList = new ArrayList<HashMap<String, String>>(); 

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

     View rootView = inflater.inflate(R.layout.activity_bank__details, 
       container, false); 
     new GetFixture().execute(); 
     return rootView; 
    } 

    private class GetFixture extends AsyncTask<Void, Void, Void> { 
     @Override 
     protected void onPreExecute() { 
      super.onPreExecute(); 
     } 

     @Override 
     protected Void doInBackground(Void... arg) { 
      ServiceHandler serviceClient = new ServiceHandler(); 
      Log.d("url: ", "> " + URL_ITEMS); 
      String json = serviceClient.makeServiceCall(URL_ITEMS, 
        ServiceHandler.GET); 
      // print the json response in the log 
      Log.d("Get match fixture response: ", "> " + json); 
      if (json != null) { 
       try { 
        Log.d("try", "in the try"); 
        JSONObject jsonObj = new JSONObject(json); 
        Log.d("jsonObject", "new json Object"); 
        // Getting JSON Array node 
        matchFixture = jsonObj.getJSONArray(TAG_COMMODITIES); 
        Log.d("json aray", "user point array"); 
        int len = matchFixture.length(); 
        Log.d("len", "get array length"); 
        for (int i = 0; i < matchFixture.length(); i++) { 
         JSONObject c = matchFixture.getJSONObject(i); 
         String Script = c.getString(TAG_SCRIPT); 
         Log.d("Script", Script); 
         String BuySell = c.getString(TAG_BUYSELL); 
         Log.d("BuySell", BuySell); 
         String TradeSell = c.getString(TAG_TRADESELL); 
         Log.d("TradeSell", TradeSell); 
         String Target = c.getString(TAG_TARGET); 
         Log.d("Target", Target); 
         String StopLoss = c.getString(TAG_STOPLOSS); 
         Log.d("StopLoss", StopLoss); 
         String Status = c.getString(TAG_STATUS); 
         Log.d("Status", Status); 

         // hashmap for single match 
         HashMap<String, String> matchFixture = new HashMap<String, String>(); 
         // adding each child node to HashMap key => value 
         matchFixture.put(TAG_SCRIPT, Script); 
         matchFixture.put(TAG_BUYSELL, BuySell); 
         matchFixture.put(TAG_TRADESELL, TradeSell); 
         matchFixture.put(TAG_TARGET, Target); 
         matchFixture.put(TAG_STOPLOSS, StopLoss); 
         matchFixture.put(TAG_STATUS, Status); 
         matchFixtureList.add(matchFixture); 
        } 
       } catch (JSONException e) { 
        Log.d("catch", "in the catch"); 
        e.printStackTrace(); 
       } 
      } else { 
       Log.e("JSON Data", "Didn't receive any data from server!"); 
      } 
      return null; 
     } 

     @Override 
     protected void onPostExecute(Void result) { 
      super.onPostExecute(result); 
      ListAdapter adapter = new SimpleAdapter(Commodities.this, 
        matchFixtureList, R.layout.list_item, new String[] { 
          TAG_SCRIPT, TAG_BUYSELL, TAG_TRADESELL, TAG_TARGET, 
          TAG_STOPLOSS, TAG_STATUS }, new int[] { 
          R.id.Script, R.id.BuySell, R.id.TradeSell, 
          R.id.Target, R.id.StopLoss, R.id.Status }); 
      setListAdapter(adapter); 
     } 
    } 
} 

Answer 1

由于Commodities是ListFragment，您不能使用this作为Context。

尝试使用Commodities.thisCommodities.this.getActivity()代替

 ListAdapter adapter = new SimpleAdapter(Commodities.this.getActivity(), 
       matchFixtureList, R.layout.list_item, new String[] { 
         TAG_SCRIPT, TAG_BUYSELL, TAG_TRADESELL, TAG_TARGET, 
         TAG_STOPLOSS, TAG_STATUS }, new int[] { 
         R.id.Script, R.id.BuySell, R.id.TradeSell, 
         R.id.Target, R.id.StopLoss, R.id.Status }); 

的Context，你需要在这里是包含此ListFragment的Activity。

从the documentation，构造函数的第一个参数是：

方面在那里与此SimpleAdapter 相关的查看正在运行

另一个要注意的方面是，你会当您致电setListAdapter()时需要使用Commodities.this：

//setListAdapter(adapter); //won't work 
Commodities.this.setListAdapter(adapter); //use this instead 

这是因为setListAdapter()是这里的ListFragment的方法，see documentation。