货币转换器无法正确转换

Question

Ok, so I am new to android studio and trying to make a Currency Converter. I am supposed to consume an API and then code it to do the converting and taking the rates from the API. But when I run it, everything works fine other than the fact that it is converting everything into 0, disregarding the user input.

I had to hard code it this way because of the API and I have no idea how to do it the easier way. Sorry for the trouble. Please do inform me if more information is needed.

Here is the code for my MainActivity2 where my converter resides in:

package com.example.justin.currencyconverter20;

import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.w3c.dom.Text;

import java.util.List;

public class MainActivity2 extends AppCompatActivity {
    private String[] arraySpinner;
    private static final String LOGIN_URL = "https://api.fixer.io/latest?base=SGD";
    List<Singapore> myCountries;
    Singapore tempSingapore;
    String operation;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        this.arraySpinner = new String[] {
                "AUD",
                "BGN",
                "BRL",
                "CAD",
                "CHF",
                "CNY",
                "CZK",
                "DKK",
                "GBP",
                "HKD",
                "HRK",
                "HUF",
                "IDR",
                "ILS",
                "INR",
                "JPY",
                "KRW",
                "MXN",
                "MYR",
                "NOK",
                "NZD",
                "PHP",
                "PLN",
                "RON",
                "RUB",
                "SEK",
                "THB",
                "TRY",
                "USD",
                "ZAR",
                "EUR"
        };
        Spinner s = (Spinner) findViewById(R.id.countryspinner1);
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item, arraySpinner);
        s.setAdapter(adapter);

        new getRates().execute();
    }
    JSONParser jsonParser = new JSONParser();

    class getRates extends AsyncTask<String, String, JSONArray> {
        private ProgressDialog progressDialog;

        @Override
        protected JSONArray doInBackground(String... args) {

            try {
                JSONArray json = jsonParser.makeHttpRequest(
                        LOGIN_URL, "GET");

                if (json != null) {
                    Log.d("JSON result", json.toString());

                    return json;
                }

            } catch (Exception e) {
                e.printStackTrace();
            }

            return null;
        }

        protected void onPostExecute(JSONArray json) {

            if (progressDialog != null && progressDialog.isShowing()) {
                progressDialog.dismiss();
            }

            if (json != null) {
                // looping through All records
                for (int i = 0; i < json.length(); i++) {

                    try {
                        JSONObject c = json.getJSONObject(i);

                        tempSingapore.setName("Singapore");
                        tempSingapore.setCurrencycode("SGD");
                        tempSingapore.setAUD(c.getDouble("AUD"));
                        tempSingapore.setBRL(c.getDouble("BRL"));
                        tempSingapore.setBGN(c.getDouble("BGN"));
                        tempSingapore.setCAD(c.getDouble("CAD"));
                        tempSingapore.setCNY(c.getDouble("CNY"));

                        tempSingapore.setCHF(c.getDouble("CHF"));
                        tempSingapore.setCZK(c.getDouble("CZK"));
                        tempSingapore.setDKK(c.getDouble("DKK"));
                        tempSingapore.setEUR(c.getDouble("EUR"));
                        tempSingapore.setGBP(c.getDouble("GBP"));

                        tempSingapore.setHKD(c.getDouble("HKD"));
                        tempSingapore.setHRK(c.getDouble("HRK"));
                        tempSingapore.setHUF(c.getDouble("HUF"));
                        tempSingapore.setIDR(c.getDouble("IDR"));
                        tempSingapore.setILS(c.getDouble("ILS"));

                        tempSingapore.setINR(c.getDouble("INR"));
                        tempSingapore.setJPY(c.getDouble("JPY"));
                        tempSingapore.setKRW(c.getDouble("KRW"));
                        tempSingapore.setMXN(c.getDouble("MXN"));
                        tempSingapore.setMYR(c.getDouble("MYR"));

                        tempSingapore.setNOK(c.getDouble("NOK"));
                        tempSingapore.setNZD(c.getDouble("NZD"));
                        tempSingapore.setPHP(c.getDouble("PHP"));
                        tempSingapore.setPLN(c.getDouble("PLN"));
                        tempSingapore.setRON(c.getDouble("RON"));

                        tempSingapore.setRUB(c.getDouble("RUB"));
                        tempSingapore.setSEK(c.getDouble("SEK"));
                        tempSingapore.setTRY(c.getDouble("TRY"));
                        tempSingapore.setTHB(c.getDouble("THB"));
                        tempSingapore.setUSD(c.getDouble("USD"));
                        tempSingapore.setZAR(c.getDouble("ZAR"));

                        String AUD = String.valueOf(c.getDouble("AUD"));
                        Toast myToast = Toast.makeText(getApplicationContext(),  AUD, Toast.LENGTH_SHORT);
                        myToast.show();

                    } catch (JSONException e) {
                        e.printStackTrace();
                    }

                }

                populate();
            }

        }
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }



    public void populate() {


    }


    public void btnGetRates (View v){
        new getRates().execute();
        TextView textView = (TextView) findViewById(R.id.textView3);
        Spinner tempSpinner = (Spinner) findViewById(R.id.countryspinner1);
        EditText editText = (EditText) findViewById(R.id.editText);

        double userText = Double.parseDouble(editText.getText().toString());
        String valOfSpinner = tempSpinner.getSelectedItem().toString();
        Singapore mySingapore = new Singapore();
        double rates = 0;

        if (valOfSpinner.equals("AUD") )
        {
            mySingapore.getAUD();
            rates = mySingapore.getAUD();
        }

        else if (valOfSpinner.equals("BGN"))
        {
            mySingapore.getBGN();
            rates = mySingapore.getBGN();
        }

        else if (valOfSpinner.equals("BRL"))
        {
            mySingapore.getBRL();
            rates = mySingapore.getBRL();
        }

        else if (valOfSpinner.equals("CAD"))
        {
            mySingapore.getCAD();
            rates = mySingapore.getCAD();
        }

        else if (valOfSpinner.equals("CHF"))
        {
            mySingapore.getCHF();
            rates = mySingapore.getCHF();
        }

        else if (valOfSpinner.equals("CNY"))
        {
            mySingapore.getCNY();
            rates = mySingapore.getCNY();
        }

        else if (valOfSpinner.equals("CZK"))
        {
            mySingapore.getCZK();
            rates = mySingapore.getCZK();
        }

        else if (valOfSpinner.equals("DKK"))
        {
            mySingapore.getDKK();
            rates = mySingapore.getDKK();
        }

        else if (valOfSpinner.equals("GBP"))
        {
            mySingapore.getGBP();
            rates = mySingapore.getGBP();
        }

        else if (valOfSpinner.equals("HKD"))
        {
            mySingapore.getHKD();
            rates = mySingapore.getHKD();
        }

        else if (valOfSpinner.equals("HRK"))
        {
            mySingapore.getHRK();
            rates = mySingapore.getHRK();
        }

        else if (valOfSpinner.equals("HUF"))
        {
            mySingapore.getHUF();
            rates = mySingapore.getHUF();
        }

        else if (valOfSpinner.equals("IDR"))
        {
            mySingapore.getIDR();
            rates = mySingapore.getIDR();
        }

        else if (valOfSpinner.equals("ILS"))
        {
            mySingapore.getILS();
            rates = mySingapore.getILS();
        }

        else if (valOfSpinner.equals("INR"))
        {
            mySingapore.getINR();
            rates = mySingapore.getINR();
        }

        else if (valOfSpinner.equals("JPY"))
        {
            mySingapore.getJPY();
            rates = mySingapore.getJPY();
        }

        else if (valOfSpinner.equals("KRW"))
        {
            mySingapore.getKRW();
            rates = mySingapore.getKRW();
        }


        else if (valOfSpinner.equals("MYR"))
        {
            mySingapore.getMYR();
            rates = mySingapore.getMYR();
        }

        else if (valOfSpinner.equals("MXN"))
        {
            mySingapore.getMXN();
            rates = mySingapore.getMXN();
        }

        else if (valOfSpinner.equals("NOK"))
        {
            mySingapore.getNOK();
            rates = mySingapore.getNOK();
        }

        else if (valOfSpinner.equals("NZD"))
        {
            mySingapore.getNZD();
            rates = mySingapore.getNZD();
        }

        else if (valOfSpinner.equals("PHP"))
        {
            mySingapore.getPHP();
            rates = mySingapore.getPHP();
        }

        else if (valOfSpinner.equals("PLN"))
        {
            mySingapore.getPLN();
            rates = mySingapore.getPLN();
        }

        else if (valOfSpinner.equals("RON"))
        {
            mySingapore.getRON();
            rates = mySingapore.getRON();
        }

        else if (valOfSpinner.equals("RUB"))
        {
            mySingapore.getRUB();
            rates = mySingapore.getRUB();
        }

        else if (valOfSpinner.equals("SEK"))
        {
            mySingapore.getSEK();
            rates = mySingapore.getSEK();
        }

        else if (valOfSpinner.equals("THB"))
        {
            mySingapore.getTHB();
            rates = mySingapore.getTHB();
        }

        else if (valOfSpinner.equals("TRY"))
        {
            mySingapore.getTRY();
            rates = mySingapore.getTRY();
        }

        else if (valOfSpinner.equals("USD"))
        {
            mySingapore.getUSD();
            rates = mySingapore.getUSD();
        }

        else if (valOfSpinner.equals("ZAR"))
        {
            mySingapore.getZAR();
            rates = mySingapore.getZAR();
        }

        else if (valOfSpinner.equals("EUR"))
        {
            mySingapore.getEUR();
            rates = mySingapore.getEUR();
        }

        double rateResult = userText * rates;
        String result = String.valueOf(rateResult);
        textView.setText(result);

    }

}

Edit2 my jsonparser class:

package com.example.justin.currencyconverter20;

import android.util.Log;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;

public class JSONParser {

    String charset = "UTF-8";
    HttpURLConnection conn;
    DataOutputStream wr;
    StringBuilder result;
    URL urlObj;
    JSONArray Obj = null;
    StringBuilder sbParams;
    String paramsString;


    public JSONArray makeHttpRequest(String url, String method) {

        int i = 0;

        if(method.equals("GET")){

            try {
                urlObj = new URL(url);

                conn = (HttpURLConnection) urlObj.openConnection();

                conn.setDoOutput(false);

                conn.setRequestMethod("GET");

                conn.setConnectTimeout(15000);

                conn.connect();

            } catch (IOException e) {
                e.printStackTrace();
            }

        }

        try {
            //Receive the response from the server
            InputStream in = new BufferedInputStream(conn.getInputStream());
            BufferedReader reader = new BufferedReader(new InputStreamReader(in));
            result = new StringBuilder();
            String line;
            while ((line = reader.readLine()) != null) {
                result.append(line);
            }

            Log.d("JSON Parser", "result: " + result.toString());

        } catch (IOException e) {
            // e.printStackTrace();
        }

        conn.disconnect();

        // try parse the string to a JSON object
        try {
            JSONObject jObj = new JSONObject(result.toString());
            JSONObject ratesObject = jObj.getJSONObject("rates");

            double AUD = ratesObject.getDouble("AUD");
            double BGN = ratesObject.getDouble("BGN");
            double BRL = ratesObject.getDouble("BRL");
            double CAD = ratesObject.getDouble("CAD");
            double CHF = ratesObject.getDouble("CHF");
            double CNY = ratesObject.getDouble("CNY");
            double CZK = ratesObject.getDouble("CZK");
            double DKK = ratesObject.getDouble("DKK");
            double GBP = ratesObject.getDouble("GBP");
            double HKD = ratesObject.getDouble("HKD");
            double HRK = ratesObject.getDouble("HRK");
            double HUF = ratesObject.getDouble("HUF");
            double IDR = ratesObject.getDouble("IDR");
            double ILS = ratesObject.getDouble("ILS");
            double INR = ratesObject.getDouble("INR");
            double JPY = ratesObject.getDouble("JPY");
            double KRW = ratesObject.getDouble("KRW");
            double MXN = ratesObject.getDouble("MXN");
            double MYR = ratesObject.getDouble("MYR");
            double NOK = ratesObject.getDouble("NOK");
            double NZD = ratesObject.getDouble("NZD");
            double PHP = ratesObject.getDouble("PHP");
            double PLN = ratesObject.getDouble("PLN");
            double RON = ratesObject.getDouble("RON");
            double RUB = ratesObject.getDouble("RUB");
            double SEK = ratesObject.getDouble("SEK");
            double THB = ratesObject.getDouble("THB");
            double TRY = ratesObject.getDouble("TRY");
            double USD = ratesObject.getDouble("USD");
            double ZAR = ratesObject.getDouble("ZAR");
            double EUR = ratesObject.getDouble("EUR");
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }

        // return JSON Object
        return Obj;
    }
}

Edit3 My JSON using JSONlint:

{
    "base": "SGD",
    "date": "2016-02-26",
    "rates": {
        "AUD": 0.99008,
        "BGN": 1.2677,
        "BRL": 2.8102,
        "CAD": 0.96636,
        "CHF": 0.70839,
        "CNY": 4.6639,
        "CZK": 17.542,
        "DKK": 4.8354,
        "GBP": 0.5104,
        "HKD": 5.5426,
        "HRK": 4.941,
        "HUF": 201.27,
        "IDR": 9537.9,
        "ILS": 2.7826,
        "INR": 49.002,
        "JPY": 80.646,
        "KRW": 881.73,
        "MXN": 12.914,
        "MYR": 3.0044,
        "NOK": 6.1735,
        "NZD": 1.0596,
        "PHP": 33.884,
        "PLN": 2.828,
        "RON": 2.8934,
        "RUB": 53.827,
        "SEK": 6.074,
        "THB": 25.432,
        "TRY": 2.0966,
        "USD": 0.71338,
        "ZAR": 11.183,
        "EUR": 0.64817
    }
}

Edit4:

Parsing is okay but cannot seem to get it in my converter after calling on the method btnGetRates. Below is my Singapore.class to set and get rates:

public class Singapore {
    private String name;
    private double AUD;
    private double BGN;
    private double BRL;
    private double CAD;
    private double CHF;
    private double CNY;
    private double CZK;
    private double DKK;
    private double GBP;
    private double HKD;
    private double HRK;
    private double HUF;
    private double IDR;
    private double ILS;
    private double INR;
    private double JPY;
    private double KRW;
    private double MXN;
    private double MYR;
    private double NOK;
    private double NZD;
    private double PHP;
    private double PLN;
    private double RON;
    private double RUB;
    private double SEK;
    private double THB;
    private double TRY;
    private double USD;
    private double ZAR;
    private double EUR;

    public String getName() {

        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getAUD() {
        return AUD;
    }

    public void setAUD(double AUD) {
        this.AUD = AUD;
    }

    public double getBGN() {
        return BGN;
    }

    public void setBGN(double BGN) {
        this.BGN = BGN;
    }

    public double getBRL() {
        return BRL;
    }

    public void setBRL(double BRL) {
        this.BRL = BRL;
    }

    public double getCAD() {
        return CAD;
    }

    public void setCAD(double CAD) {
        this.CAD = CAD;
    }

    public double getCHF() {
        return CHF;
    }

    public void setCHF(double CHF) {
        this.CHF = CHF;
    }

    public double getCNY() {
        return CNY;
    }

    public void setCNY(double CNY) {
        this.CNY = CNY;
    }

    public double getCZK() {
        return CZK;
    }

    public void setCZK(double CZK) {
        this.CZK = CZK;
    }

    public double getDKK() {
        return DKK;
    }

    public void setDKK(double DKK) {
        this.DKK = DKK;
    }

    public double getGBP() {
        return GBP;
    }

    public void setGBP(double GBP) {
        this.GBP = GBP;
    }

    public double getHKD() {
        return HKD;
    }

    public void setHKD(double HKD) {
        this.HKD = HKD;
    }

    public double getHRK() {
        return HRK;
    }

    public void setHRK(double HRK) {
        this.HRK = HRK;
    }

    public double getHUF() {
        return HUF;
    }

    public void setHUF(double HUF) {
        this.HUF = HUF;
    }

    public double getIDR() {
        return IDR;
    }

    public void setIDR(double IDR) {
        this.IDR = IDR;
    }

    public double getILS() {
        return ILS;
    }

    public void setILS(double ILS) {
        this.ILS = ILS;
    }

    public double getINR() {
        return INR;
    }

    public void setINR(double INR) {
        this.INR = INR;
    }

    public double getJPY() {
        return JPY;
    }

    public void setJPY(double JPY) {
        this.JPY = JPY;
    }

    public double getKRW() {
        return KRW;
    }

    public void setKRW(double KRW) {
        this.KRW = KRW;
    }

    public double getMXN() {
        return MXN;
    }

    public void setMXN(double MXN) {
        this.MXN = MXN;
    }

    public double getMYR() {
        return MYR;
    }

    public void setMYR(double MYR) {
        this.MYR = MYR;
    }

    public double getNOK() {
        return NOK;
    }

    public void setNOK(double NOK) {
        this.NOK = NOK;
    }

    public double getNZD() {
        return NZD;
    }

    public void setNZD(double NZD) {
        this.NZD = NZD;
    }

    public double getPHP() {
        return PHP;
    }

    public void setPHP(double PHP) {
        this.PHP = PHP;
    }

    public double getPLN() {
        return PLN;
    }

    public void setPLN(double PLN) {
        this.PLN = PLN;
    }

    public double getRON() {
        return RON;
    }

    public void setRON(double RON) {
        this.RON = RON;
    }

    public double getRUB() {
        return RUB;
    }

    public void setRUB(double RUB) {
        this.RUB = RUB;
    }

    public double getSEK() {
        return SEK;
    }

    public void setSEK(double SEK) {
        this.SEK = SEK;
    }

    public double getTHB() {
        return THB;
    }

    public void setTHB(double THB) {
        this.THB = THB;
    }

    public double getTRY() {
        return TRY;
    }

    public void setTRY(double TRY) {
        this.TRY = TRY;
    }

    public double getUSD() {
        return USD;
    }

    public void setUSD(double USD) {
        this.USD = USD;
    }

    public double getZAR() {
        return ZAR;
    }

    public void setZAR(double ZAR) {
        this.ZAR = ZAR;
    }

    public double getEUR() {
        return EUR;
    }

    public void setEUR(double EUR) {
        this.EUR = EUR;
    }
}

And the result of the parsing:

03-01 05:23:36.050 13219-13400/com.example.justin.currencyconverter20 D/JSON Parser: result: {"base":"SGD","date":"2016-02-29","rates":{"AUD":0.99576,"BGN":1.2762,"BRL":2.8316,"CAD":0.96359,"CHF":0.71217,"CNY":4.6559,"CZK":17.655,"DKK":4.868,"GBP":0.51276,"HKD":5.5237,"HRK":4.9764,"HUF":203.11,"IDR":9500.4,"ILS":2.7769,"INR":48.537,"JPY":80.352,"KRW":879.31,"MXN":12.92,"MYR":2.9931,"NOK":6.2018,"NZD":1.0804,"PHP":33.68,"PLN":2.8413,"RON":2.9205,"RUB":53.927,"SEK":6.0828,"THB":25.336,"TRY":2.1059,"USD":0.71047,"ZAR":11.391,"EUR":0.65253}}

Still converting any value to 0 after changes to parser.

Answer 1

You need to use object in which you have saved the rates (ie; tempSingapore ). Rather than doing that you are using a new object which has no data set inside it causing the conversion to be 0.

Initialize your variable like Singapore tempSingapore = new Singapore (); then

Change

 Singapore mySingapore = new Singapore();

to

 Singapore mySingapore = tempSingapore;

in btnGetRates

Update: Just saw your JSON is also not valid. Check your JSON at http://jsonlint.com/