使用AsyncHttpClient的列表视图

Question

我想用ListView AsyncHttpClient填充一些值为ListView。

我不知道如何与AsyncHttpClient

public void getFavouriteWS(RequestParams params){ 
    // Make RESTful webservice call using AsyncHttpClient object 
    AsyncHttpClient client = new AsyncHttpClient(); 
    client.get("http://www.example.com/getfavouriteonline",params ,new AsyncHttpResponseHandler() { 
     // When the response returned by REST has Http response code '200' 
     @Override 
     public void onSuccess(String response) { 
      try { 
       // JSON Object 
       JSONObject obj = new JSONObject(response); 
       String favourite_id = obj.getString("favourite_online_id"); 
      } catch (JSONException e) { 
       // TODO Auto-generated catch block 
       Toast.makeText(getActivity(), "Error Occured [Server's JSON response might be invalid]!", Toast.LENGTH_LONG).show(); 
       e.printStackTrace(); 
      } 
     } 
     // When the response returned by REST has Http response code other than '200' 
     @Override 
     public void onFailure(int statusCode, Throwable error, String content) { 
      // When Http response code is '404' 
      if(statusCode == 404){ 
       Toast.makeText(getActivity(), "Requested resource not found", Toast.LENGTH_LONG).show(); 
      } 
      // When Http response code is '500' 
      else if(statusCode == 500){ 
       Toast.makeText(getActivity(), "Something went wrong at server end", Toast.LENGTH_LONG).show(); 
      } 
      // When Http response code other than 404, 500 
      else{ 
       Toast.makeText(getActivity(), "Unexpected Error occcured! [Most common Error: Device might not be connected to Internet or remote server is not up and running]", Toast.LENGTH_LONG).show(); 
      } 
     } 
    }); 
} 

我的JSON响应为做到这一点，

{"favourite_online_id":"3","favourite_online_url":"ddd","favourite_online_status":"0"}{"favourite_online_id":"2","favourite_online_url":"http:\/\/www.google.com","favourite_online_status":"0"} 

如何填充在ListView上述JSON响应。

Answer 1

有几个步骤才能使其工作。首先，我们需要来自您的API的有效JSON。我通过myJSON建立了一个临时端点，您可以使用它来测试https://api.myjson.com/bins/ssc03。按照这种格式：

[ 
    { 
    "favourite_online_id": "3", 
    "favourite_online_url": "ddd", 
    "favourite_online_status": "0" 
    }, 
    { 
    "favourite_online_id": "2", 
    "favourite_online_url": "http://www.google.com", 
    "favourite_online_status": "0" 
    } 
] 

既然JSON是有效的，我们可以解析它。我使用的ASyncHttpClient版本采用不同的参数，因此只关注内部的逻辑。

ArrayList<String> values = new ArrayList<>(); 

public void getFavouriteWS(RequestParams params){ 
    // Make RESTful webservice call using AsyncHttpClient object 
    AsyncHttpClient client = new AsyncHttpClient(); 
    client.get("https://api.myjson.com/bins/ssc03",params ,new AsyncHttpResponseHandler() { 
     @Override 
     public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) { 
      try { 
       // JSON Array from byte[] 
       JSONArray arr = new JSONArray(new String(responseBody)); 
       //loop each object in the array 
       for(int i = 0; i< arr.length(); i++) { 
        // get value needed 
        String favourite_id = arr.getJSONObject(i).getString("favourite_online_id"); 
        // add value to arrayList 
        values.add(favourite_id); 
       } 
       // call method to show results 
       populateList(); 

      } catch (JSONException e) { 
       // TODO Auto-generated catch block 
       Toast.makeText(MainActivity.this, "Error Occured [Server's JSON response might be invalid]!", Toast.LENGTH_LONG).show(); 
       e.printStackTrace(); 
      } 
     } 

     @Override 
     public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable error) { 
      // When Http response code is '404' 
      if(statusCode == 404){ 
       Toast.makeText(MainActivity.this, "Requested resource not found", Toast.LENGTH_LONG).show(); 
      } 
      // When Http response code is '500' 
      else if(statusCode == 500){ 
       Toast.makeText(MainActivity.this, "Something went wrong at server end", Toast.LENGTH_LONG).show(); 
      } 
      // When Http response code other than 404, 500 
      else{ 
       Toast.makeText(MainActivity.this, "Unexpected Error occcured! [Most common Error: Device might not be connected to Internet or remote server is not up and running]", Toast.LENGTH_LONG).show(); 
      } 
     } 
    }); 
} 

为了测试目的，我在同一个文件中做了所有这些。如果你想把你的API调用封装到一个单独的文件中，你需要创建一个从API调用到你的活动或片段的回调。在你的列表视图引用文件内做这样的事情：

public void populateList(){ 
    //create simple adapter 
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, 
      android.R.layout.simple_list_item_1, android.R.id.text1, values); 
    //assign adapter to listview 
    listView.setAdapter(adapter); 
}