Question

我老老实实地尝试过这么多教程并且做得很短。有人可以指导我如何从网址中获取一个简单的JSON数组，然后在Android工作室中填充listview。我尝试过的大部分教程都已过时且已弃用。请真正感谢任何帮助。

来自网址的Json数组：

[
 { 
  "lot":"A", 
  "spaces":"100",
  "rates":"7.00"
 },
 {
  "lot":"B",
  "spaces":"207",
  "rates":"5.00"
 }
]

我尝试过凌空，httpcall和其他各种方法。我可以在任何地方找到简单的指南吗？

Answer 1

您可以使用以下代码

 public class MyActivity extends Activity {
    ListView list;
    ArrayList<Data> myList;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);

      list = (ListView) findViewById(R.id.list);
      myList = new ArrayList<>();
      LoadData sl=new LoadData();
                        sl.execute();
  }
}
        class LoadData extends AsyncTask<String, String, String>{
            ProgressDialog pd;
            @Override
            protected void onPreExecute() {
                // TODO Auto-generated method stub
                super.onPreExecute();
                pd=new ProgressDialog(Login.this);
                pd.setCancelable(false);
                pd.setMessage(getString(R.string.loading_login));
                pd.show();
            }
            @Override
            protected String doInBackground(String... params) {
                // TODO Auto-generated method stub
                String buffervalue="";


                try{
    //              StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
    //              StrictMode.setThreadPolicy(policy); 
                  DefaultHttpClient httpclient = new DefaultHttpClient();

                  HttpPost httpget = new HttpPost("url");
                  HttpResponse response = httpclient.execute(httpget);

                  InputStream inputStream = response.getEntity().getContent();

                  byte[] data = new byte[256];

                  StringBuffer buffer = new StringBuffer();
                  int len = 0;
                  while (-1 != (len = inputStream.read(data)) )
                  {
                      buffer.append(new String(data, 0, len));
                  }
                  inputStream.close();
                  buffervalue=buffer.toString();
                }catch(Exception e){

                }

                  return buffervalue;

            }
            @Override
            protected void onPostExecute(String result) {
                // TODO Auto-generated method stub
                super.onPostExecute(result);
                JSONObject jsonobject;
                try {
                    JSONArray jarr = new JSONArray(result);
                    int lengthJsonArr = jarr.length();  
                    if(lengthJsonArr>0)
                    {   
                        for(int i=0;i<lengthJsonArr;i++){
                        JsonObject obj = jarr.get(i);
                        Data data = new Data();
                        data.setLot(obj.getString("lot"));  
                        data.setSpaces(obj.getString("spaces"));
                        data.setRates(obj.getString("rates"));

                       myList.add(data)
                    }
                    adapter.notifyDataSetChanged();
                        }else{
                            Toast.makeText(getApplicationContext(),R.string.label_internet, Toast.LENGTH_SHORT).show();
                        }
                    }
                }catch(Exception e){
                    Toast.makeText(getApplicationContext(),"Something wrong with url...", Toast.LENGTH_SHORT).show();
                }
                pd.dismiss();
            }
        }

Answer 2

在android中使用这种简单易用的技术进行json解析。

saveen-android.blogspot.in/2014/10/json-parsing.html?m=1

Answer 3

希望以下链接可以帮助您，因为您可以下载源代码：

Android Studio使用来自url的JSON填充listview

3 个答案: