Question

I am trying to use JSON and HTTP client to retrieve data from a table in my database. The code I have seems to be working but it is not outputting anything, but if I change something on purpose in the query the error toast outputs, so I know the code is right as no error outputs. The problem is figuring out how to get the JSON output onto my view screen.

Here is the complete HTTP code:

public void LoadRemote()
{

     ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
    //http post
    try{
         HttpClient httpclient = new DefaultHttpClient();
         HttpPost httppost = new HttpPost("http://deucalion0.co.uk/getscores.php");
         httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
         HttpResponse response = httpclient.execute(httppost);
         HttpEntity entity = response.getEntity();
         is = entity.getContent();
         }catch(Exception e){
             Log.e("log_tag", "Error in http connection"+e.toString());
        }

   //convert response to string
 try{
       BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
        sb = new StringBuilder();
        sb.append(reader.readLine() + "\n");

        String line="0";
        while ((line = reader.readLine()) != null) {
                       sb.append(line + "\n");
         }
         is.close();
         result=sb.toString();
         }catch(Exception e){
               Log.e("log_tag", "Error converting result "+e.toString());
         }
 //paring data
 int score;
 String username;
 try{
       jArray = new JSONArray(result);
       JSONObject json_data=null;
       for(int i=0;i<jArray.length();i++){
              json_data = jArray.getJSONObject(i);
              score=json_data.getInt("score");
              username=json_data.getString("username");
          }
       }
       catch(JSONException e1){
          Toast.makeText(getBaseContext(), "No City Found" ,Toast.LENGTH_LONG).show();
       } catch (ParseException e1) {
            e1.printStackTrace();
    }
 }

Here is my SQL query:

$sql=mysql_query("select score, username from highscores ");
while($row=mysql_fetch_assoc($sql))
$output[]=$row;
print(json_encode($output));

You can see this working here

I would appreciate any advice on this issue.

Thanks.

I have started again due to complications, here is the activity class as it is now:

public class Viewscores extends Activity{

Button scores;
  @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.viewscores);

    scores = (Button) findViewById(R.id.bViewscores);

    scores.setOnClickListener(new View.OnClickListener(){

        public void onClick(View v) {

            LoadRemote();
        }

    });

}


  public void LoadRemote()
    {

   String result = "";
   ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
     InputStream is = null;
     try{
         HttpClient httpclient = new DefaultHttpClient();
         HttpPost httppost = new                HttpPost("http://deucalion0.co.uk/getscores.php");
         httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
         HttpResponse response = httpclient.execute(httppost);
         HttpEntity entity = response.getEntity();
         is = entity.getContent();
         }catch(Exception e){
             Log.e("log_tag", "Error in http connection"+e.toString());
        }

BufferedReader myReader = new BufferedReader(new InputStreamReader(is));



    }


     }

Answer 1

ok.. here is the entire code …

public class Viewscores extends Activity{

Button scores;
  @Override
    public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.viewscores);

scores = (Button) findViewById(R.id.bViewscores);

scores.setOnClickListener(new View.OnClickListener(){

    public void onClick(View v) {

        Intent i=new Intent(this,lst.class);
startActivity(i);
    }

});

}

here is the “lst” class

public class lst extends ListActivity{
JSONArray jArray; 
String result = null; 
InputStream is = null; 
StringBuilder sb=null;  
String s[];

@Override 
public void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 

try{ 
URL u=new URL("http://deucalion0.co.uk/getscores.php");
URLConnection tc=u.openConnection();
BufferedReader reader = new BufferedReader(new InputStreamReader(tc.getInputStream())); 


String line; 

while ((line = reader.readLine()) != null) { 
jArray =new JSONArray(line);
s=new String[jArray.length()];
for(int m=0;m<jArray.length();m++){
    JSONObject json_data=(JSONObject)jArray.get(m);

    s[m]=json_data.getInt("score")+" "+json_data.getString("username"); 
}
} 

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, 
android.R.layout.simple_list_item_1, s); 
setListAdapter(adapter); 
} 

catch(JSONException e1){ 
} catch (ParseException e1) { 
e1.printStackTrace(); 
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} 
}                   |
}                                        ---

This one works for sure… try this… 🙂