Listview is getting the value twice

Question

I have a API which responds in JSON. When I clicked a button I am comfortably parse the JSON and implement it in the listview. The problem is When I go back to the previous activity and clicked the button once again I am getting the values repeat. i.e. previous values also, even I had called finish(); in on pause state of the listview activity. Following is my code.

Invoice Class

public class Invoice extends Activity{

public static ArrayList<HashMap<String, String>> ModuleName = new ArrayList<HashMap<String, String>>();

boolean tree = true;
ArrayList<String> KEY = new ArrayList<String>();
ListView mListView;
ProgressBar mProgress;
JSONObject json;
JSONArray Module_list = null;
Invoice_adapter adapter;

    public static String KEY_SUCCESS = "success";
    public static String KEY_ERROR = "error";
    public static String KEY_ERROR_MSG = "error_msg";
    public static String KEY_MODULELIST_MODULEHEADER =  "moduleHeader";
    public static String KEY_MODULELIST_MODULELIST =  "moduleList";
    public static String KEY_MODULELIST_DATAFOUND =  "datafound";


    public static String KEY_INVOICE_INVOICENO =  "";
    public static String KEY_INVOICE_SUBJECT =  "";
    public static String KEY_INVOICE_SALESORDER =  "";
    public static String KEY_INVOICE_STATUS =  "";
    public static String KEY_INVOICE_TOTAL =  "";
    public static String KEY_INVOICE_ASSIGNEDTO =  "";
    public static String KEY_INVOICE_RECORDID =  "";
    public static String KEY_INVOICE_ACTION =  "";

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_module_data);

    mListView = (ListView) findViewById(R.id.module_list);
    mProgress = (ProgressBar) findViewById(R.id.progressBar1);


    try {
        json = new ParseDATA().execute().get();
    } catch (InterruptedException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    } catch (ExecutionException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }


    try {
        if (json.getString(KEY_SUCCESS) != null) {
            String res = json.getString(KEY_SUCCESS); 
            if(Integer.parseInt(res) == 1){

                String data_found = json.getString(KEY_MODULELIST_DATAFOUND);

                if (data_found.equals("Data Found!")){




                JSONArray array = json.getJSONArray(KEY_MODULELIST_MODULELIST);

                int count1 = array.length();
                String Count1 = Integer.toString(count1);
                Log.d("Count_array", Count1);

                JSONObject keyarray = array.getJSONObject(0);
            @SuppressWarnings("rawtypes")
            Iterator temp = keyarray.keys();
                    while (temp.hasNext()) {
                                String curentkey = (String) temp.next();
                                KEY.add(curentkey);


                    }


                    Collections.sort(KEY, String.CASE_INSENSITIVE_ORDER);

                    KEY_INVOICE_ACTION =  KEY.get(0);
                     KEY_INVOICE_ASSIGNEDTO =  KEY.get(1);
                     KEY_INVOICE_INVOICENO =  KEY.get(2);
                     KEY_INVOICE_RECORDID =  KEY.get(3);
                     KEY_INVOICE_SALESORDER =  KEY.get(4);
                     KEY_INVOICE_STATUS =  KEY.get(5);
                     KEY_INVOICE_SUBJECT =  KEY.get(6);
                     KEY_INVOICE_TOTAL =  KEY.get(7);



                    Log.d("Parsing Json class", "  ---- KEYS---- " + KEY);


                Module_list = json.getJSONArray(KEY_MODULELIST_MODULELIST);

                int count = Module_list.length();
                String Count = Integer.toString(count);
                Log.d("Count_Module_LIST", Count);

                // looping through All Contacts
                for(int i = 0; i < Module_list.length(); i++){
                    JSONObject c = Module_list.getJSONObject(i);

                    // Storing each json item in variable
                    String mAction = c.getString(KEY_INVOICE_ACTION);
                    String mAssignedTo = c.getString(KEY_INVOICE_ASSIGNEDTO);
                    String mInvoice = c.getString(KEY_INVOICE_INVOICENO);
                    String mRecordid = c.getString(KEY_INVOICE_RECORDID);
                    String mSalesorder = c.getString(KEY_INVOICE_SALESORDER);
                    String mStatus = c.getString(KEY_INVOICE_STATUS);
                    String mSubject = c.getString(KEY_INVOICE_SUBJECT);
                    String mTotal = c.getString(KEY_INVOICE_TOTAL);  
                    // creating new HashMap

                    HashMap<String, String> map = new HashMap<String, String>();

                    // adding each child node to HashMap key => value
                    map.put(KEY_INVOICE_ACTION, mAction);
                    map.put(KEY_INVOICE_ASSIGNEDTO, mAssignedTo);
                    map.put(KEY_INVOICE_INVOICENO, mInvoice);
                    map.put(KEY_INVOICE_RECORDID, mRecordid);
                    map.put(KEY_INVOICE_SALESORDER, mSalesorder);
                    map.put(KEY_INVOICE_STATUS, mStatus);
                    map.put(KEY_INVOICE_SUBJECT, mSubject);
                    map.put(KEY_INVOICE_TOTAL, mTotal);


                    // adding HashList to ArrayList


                    ModuleName.add(map);                  

                }
            }else 
            {
                Toast.makeText(getApplicationContext(), "No Data", Toast.LENGTH_LONG).show();
                return;
            }
            }

            mProgress.setVisibility(View.INVISIBLE);                
            adapter = new Invoice_adapter(Invoice.this, ModuleName);
            mListView.setAdapter(adapter);
            mListView.setVisibility(View.VISIBLE);
            //mListView.invalidateViews();

        }
            else 
            {

                HashMap<String, String> map = new HashMap<String, String>();

                // adding each child node to HashMap key => value
                map.put(KEY_ERROR, "Error");
                ModuleName.add(map);
                //JSONObject json_user = json.getJSONObject("user");
                //error_message = json_user.getString(KEY_ERROR_MSG);
            }


    }catch (JSONException e) {

        e.printStackTrace();
        Toast.makeText(getApplicationContext(), "Something went wrong.Please try again.!!", Toast.LENGTH_LONG).show();

    }


}



 class ParseDATA extends AsyncTask<Void, String,JSONObject  >

    {


        ProgressDialog dialog = new ProgressDialog(Invoice.this);




        @Override
        protected void onPreExecute() {
            // TODO Auto-generated method stub

            dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
            dialog.setTitle("Loading");
            dialog.setIndeterminate(true);
            dialog.setMessage("Please wait");
            dialog.setCancelable(false);
            dialog.show();

        }



        @Override
        protected JSONObject doInBackground(
                Void... params) {
            // TODO Auto-generated method stub

            UserFunctions userFunction = new UserFunctions();

            JSONObject json = userFunction.getModuleList("1", "20", "Invoice");

            return json;
        }


        @Override
        protected void onPostExecute(JSONObject result) {
            // TODO Auto-generated method stub  

            dialog.dismiss();

        }
    }



@Override
protected void onPause() {
    // TODO Auto-generated method stub
    super.onPause();
    Toast.makeText(getApplicationContext(), "PAUSE STATE", Toast.LENGTH_LONG).show();
    finish();
}}

Adapter class

public class Invoice_adapter extends BaseAdapter {


private Activity activity;
private ArrayList<HashMap<String, String>> data;
private static LayoutInflater inflater=null;


public Invoice_adapter(Activity a, ArrayList<HashMap<String, String>> d) {
    activity = a;
    data=d; 
    inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
   }


public int getCount() {
    return data.size();
}

public Object getItem(int position) {
    return data.get(position);

}

public long getItemId(int position) {
    return position;
}



public View getView(int position, View convertView, ViewGroup parent) {
    View vi=convertView;

    if(convertView==null)

        vi = inflater.inflate(R.layout.activity_module_data_detail, null);

    TextView title = (TextView)vi.findViewById(R.id.textView1); // category title name
    //ImageView moduleImage = (ImageView) vi.findViewById(R.id.recipe_image);
    HashMap<String, String> song = new HashMap<String, String>();
    song = data.get(position);

    Log.i("list", ""+data.get(position));
    //Log.i("list", data); 

    String ff = song.get(Invoice.KEY_INVOICE_SUBJECT);

   title.setText(ff);
   //moduleImage.setImageResource(mModuleImages[position]);

    return vi;


}}

Please Help.. !! I dnt know what Is I am doing wrong. Thanks in advance.

Answer 1

The problem is with the "static" key word for the ArrayList

public static ArrayList<HashMap<String, String>> ModuleName = new ArrayList<HashMap<String, String>>();

static variables are initialized only when the class is loaded, that means the value will be persisted till the end of the application process.

Either remove static keyword for array list or clear the array list before you load new data.

ModuleName.clear();