How to get response from webview after send the request to client

Question

I am new here. I am facing this issue last 3 days. we have Web application and Android application.

In Web application we receive requests (POST method) from clients and redirect to a success or failure URL depending on the outcome.

Now problem with Android application: Using Webview I am sending same request to server. my code is executing but I don't know few things.

1. what will be the success and failure URL for Android?

2. how to get response from client side and get back to the activity?

by default I give success URL is Google.com and failure URL is Gmail.com. If I give my Web application success and failure URL it will give response in server side.

Note: In this code JavaScript code there I don't know how to use. I refer somewhere else. PayUJavaScriptInterface, success(), and popup() method not using. If I have to use for getting response then tell me how to use.

Here is my code for my activity

 public class PayMentGateWay extends Activity {
 private ArrayList<String> post_val = new ArrayList<String>();
 private String post_Data="";
 WebView webView ;
 final Activity activity = this;
 private String tag = "PayMentGateWay";
 private String hash,hashSequence;
 String merchant_key="JBZaLc";
    String salt="GQs7yium";
    String action1 ="";
    String base_url="https://test.payu.in";
    int error=0;
    String hashString="";
    Map<String,String> params;
    String txnid ="";

    Handler mHandler = new Handler();


@SuppressLint("JavascriptInterface")
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
     final ProgressDialog progressDialog = new ProgressDialog(activity);
     getWindow().requestFeature(Window.FEATURE_PROGRESS);
    webView = new WebView(this);
    setContentView(webView);

    post_val.add("key");
    post_val.add("JBZaLc");
    post_val.add("txnid");
    post_val.add("5d59dae66618a14f5020");
    post_val.add("amount");
    post_val.add("100.00");
    post_val.add("productinfo");

    post_val.add("{paymentParts:[{name:abc,description:abcd,value:500,isRequired:true,settlementEvent:EmailConfirmation}], paymentIdentifiers:[{field:CompletionDate, value:25/06/2015}]}");
    post_val.add("firstname");
    post_val.add("pqrs");
    post_val.add("email");
    post_val.add("xxxx@xxxmail.com");
    post_val.add("phone");
    post_val.add("xxxxxxxxxx");
    post_val.add("surl");
    post_val.add("https://www.google.com");
    post_val.add("furl");
    post_val.add("https://www.gmail.com");
    post_val.add("hash");
    post_val.add("");
    post_val.add("provider");
    post_val.add("payu_paisa");
    Log.d(tag, "post_val: "+post_val);
    params= new HashMap<String,String>();
    for(int i = 0;i<post_val.size();){
        params.put(post_val.get(i), post_val.get(i+1));

        i+=2;   
    }

    if(empty(params.get("txnid"))){
        Random rand = new Random();
        String rndm = Integer.toString(rand.nextInt())+(System.currentTimeMillis() / 1000L);
        txnid=hashCal("SHA-256",rndm).substring(0,20);
        popup("txnid : " + txnid);
        System.out.println("......txnid...... " + txnid);
    } else {
        txnid=params.get("txnid");
        System.out.println("....else.......txnid...... " + txnid);
    }

        //String udf2 = txnid;
    String txn="abcd";
     hash="";
    String hashSequence = "key|txnid|amount|productinfo|firstname|email|udf1|udf2|udf3|udf4|udf5|udf6|udf7|udf8|udf9|udf10";
    if(empty(params.get("hash")) && params.size()>0) {
        if( empty(params.get("key"))
            || empty(params.get("txnid"))
            || empty(params.get("amount"))
            || empty(params.get("firstname"))
            || empty(params.get("email"))
            || empty(params.get("phone"))
            || empty(params.get("productinfo"))
            || empty(params.get("surl"))
            || empty(params.get("furl"))
            || empty(params.get("service_provider"))

    ) {
            String[] hashVarSeq = hashSequence.split("\\|");
            for (int i = 0; i < hashVarSeq.length; i++) {
                System.out.println("<<<<<>>>>>>>> " + hashVarSeq[i]);
            }

            for(String part : hashVarSeq)
            {
                hashString= (empty(params.get(part))) ? hashString.concat("") : hashString.concat(params.get(part));
                hashString=hashString.concat("|");
                System.out.println("??????? " + hashString);
            }
            hashString=hashString.concat(salt);


             hash=hashCal("SHA-512",hashString);
             System.out.println(hashString + " /////~~~~~~ " + hash);
            action1=base_url.concat("/_payment");
        }
    }
    else if(!empty(params.get("hash")))
    {
        hash=params.get("hash");
        action1=base_url.concat("/_payment");
        System.out.println("!!!!!!!!HASHHHHHHH!!!!!! " + hash);
    }

    webView.setWebViewClient(new WebViewClient(){


        @Override
        public void onReceivedError(WebView view, int errorCode,
                String description, String failingUrl) {
            // TODO Auto-generated method stub
            System.out.println(">>>>>>>>>>>>>>onReceivedError>>>>>>>>>>>>>>>>>>");
            Toast.makeText(activity, "Oh no! " + description, Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onReceivedSslError(WebView view,
                SslErrorHandler handler, SslError error) {
            // TODO Auto-generated method stub
            System.out.println(">>>>>>>>>>>>>>onReceivedSslError>>>>>>>>>>>>>>>>>>");
            Toast.makeText(activity, "SslError! " +  error, Toast.LENGTH_SHORT).show();
             handler.proceed();
        }

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            // TODO Auto-generated method stub
            System.out.println(">>>>>>>>>>>>>>shouldOverrideUrlLoading>>>>>>>>>>>>>>>>>>");
            return super.shouldOverrideUrlLoading(view, url);
        }

        @Override
        public void onPageFinished(WebView view, String url) {
            // TODO Auto-generated method stub
            super.onPageFinished(view, url);
            System.out.println(">>>>>>>>>>>>>>onPageFinished>>>>>>>>>>>>>>>>>>");
        }


    });


    webView.setVisibility(0);
    webView.getSettings().setBuiltInZoomControls(true);
    webView.getSettings().setCacheMode(2);
    webView.getSettings().setDomStorageEnabled(true);
    webView.clearHistory();
    webView.clearCache(true);
    webView.getSettings().setJavaScriptEnabled(true);
    webView.getSettings().setSupportZoom(true);
    webView.getSettings().setUseWideViewPort(false);
    webView.getSettings().setLoadWithOverviewMode(false);

    webView.addJavascriptInterface(new PayUJavaScriptInterface(activity), "PayUMoney");
    Map<String, String> mapParams = new HashMap<String, String>();
    mapParams.put("key",merchant_key);
    mapParams.put("hash",PayMentGateWay.this.hash);
    mapParams.put("txnid",(empty(PayMentGateWay.this.params.get("txnid"))) ? "" : PayMentGateWay.this.params.get("txnid"));
    Log.d(tag, "txnid: "+PayMentGateWay.this.params.get("txnid"));
    mapParams.put("service_provider","payu_paisa");

        mapParams.put("amount",(empty(PayMentGateWay.this.params.get("amount"))) ? "" : PayMentGateWay.this.params.get("amount"));
        mapParams.put("firstname",(empty(PayMentGateWay.this.params.get("firstname"))) ? "" : PayMentGateWay.this.params.get("firstname"));
        mapParams.put("email",(empty(PayMentGateWay.this.params.get("email"))) ? "" : PayMentGateWay.this.params.get("email"));
        mapParams.put("phone",(empty(PayMentGateWay.this.params.get("phone"))) ? "" : PayMentGateWay.this.params.get("phone"));

        mapParams.put("productinfo",(empty(PayMentGateWay.this.params.get("productinfo"))) ? "" : PayMentGateWay.this.params.get("productinfo"));
        mapParams.put("surl",(empty(PayMentGateWay.this.params.get("surl"))) ? "" : PayMentGateWay.this.params.get("surl"));
        mapParams.put("furl",(empty(PayMentGateWay.this.params.get("furl"))) ? "" : PayMentGateWay.this.params.get("furl"));
        mapParams.put("lastname",(empty(PayMentGateWay.this.params.get("lastname"))) ? "" : PayMentGateWay.this.params.get("lastname"));

        mapParams.put("address1",(empty(PayMentGateWay.this.params.get("address1"))) ? "" : PayMentGateWay.this.params.get("address1"));
        mapParams.put("address2",(empty(PayMentGateWay.this.params.get("address2"))) ? "" : PayMentGateWay.this.params.get("address2"));
        mapParams.put("city",(empty(PayMentGateWay.this.params.get("city"))) ? "" : PayMentGateWay.this.params.get("city"));
        mapParams.put("state",(empty(PayMentGateWay.this.params.get("state"))) ? "" : PayMentGateWay.this.params.get("state"));

        mapParams.put("country",(empty(PayMentGateWay.this.params.get("country"))) ? "" : PayMentGateWay.this.params.get("country"));
        mapParams.put("zipcode",(empty(PayMentGateWay.this.params.get("zipcode"))) ? "" : PayMentGateWay.this.params.get("zipcode"));
        mapParams.put("udf1",(empty(PayMentGateWay.this.params.get("udf1"))) ? "" : PayMentGateWay.this.params.get("udf1"));
        mapParams.put("udf2",(empty(PayMentGateWay.this.params.get("udf2"))) ? "" : PayMentGateWay.this.params.get("udf2"));

        mapParams.put("udf3",(empty(PayMentGateWay.this.params.get("udf3"))) ? "" : PayMentGateWay.this.params.get("udf3"));
        mapParams.put("udf4",(empty(PayMentGateWay.this.params.get("udf4"))) ? "" : PayMentGateWay.this.params.get("udf4"));
        mapParams.put("udf5",(empty(PayMentGateWay.this.params.get("udf5"))) ? "" : PayMentGateWay.this.params.get("udf5"));
        mapParams.put("pg",(empty(PayMentGateWay.this.params.get("pg"))) ? "" : PayMentGateWay.this.params.get("pg"));
        webview_ClientPost(webView, action1, mapParams.entrySet());

}
public class PayUJavaScriptInterface {
    Context mContext;

    /** Instantiate the interface and set the context */
    PayUJavaScriptInterface(Context c) {
        mContext = c;
    }


    public void success(long id, final String paymentId) {

    mHandler.post(new Runnable() {

    public void run() {

    mHandler = null;

    Intent intent = new Intent(PayMentGateWay.this, MainActivity.class);

    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP |Intent.FLAG_ACTIVITY_SINGLE_TOP);

    intent.putExtra("result", "success");

    intent.putExtra("paymentId", paymentId);

    startActivity(intent);

    finish();

    }

    });

    }

}
 public void webview_ClientPost(WebView webView, String url, Collection< Map.Entry<String, String>> postData){
        StringBuilder sb = new StringBuilder();

        sb.append("<html><head></head>");
        sb.append("<body onload='form1.submit()'>");
        sb.append(String.format("<form id='form1' action='%s' method='%s'>", url, "post"));
        for (Map.Entry<String, String> item : postData) {
            sb.append(String.format("<input name='%s' type='hidden' value='%s' />", item.getKey(), item.getValue()));
        }
        sb.append("</form></body></html>");
        Log.d(tag, "webview_ClientPost called");
       webView.loadData(sb.toString(), "text/html", "utf-8");
 }


 public void success(long id, final String paymentId) {

 mHandler.post(new Runnable() {

 public void run() {

 mHandler = null;

 Intent intent = new Intent(PayMentGateWay.this, MainActivity.class);

 intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP |Intent.FLAG_ACTIVITY_SINGLE_TOP);

 intent.putExtra(Constants.ACCOUNT_NAME, "success");

 intent.putExtra(Constants._ID, paymentId);

 startActivity(intent);

 finish();

 }

 });

 }


public boolean empty(String s)
{
    if(s== null || s.trim().equals(""))
        return true;
    else
        return false;
}

public String hashCal(String type,String str){
    byte[] hashseq=str.getBytes();
    StringBuffer hexString = new StringBuffer();
    try{
    MessageDigest algorithm = MessageDigest.getInstance(type);
    algorithm.reset();
    algorithm.update(hashseq);
    byte messageDigest[] = algorithm.digest();



    for (int i=0;i<messageDigest.length;i++) {
        String hex=Integer.toHexString(0xFF & messageDigest[i]);
        if(hex.length()==1) hexString.append("0");
        hexString.append(hex);
    }

    }catch(NoSuchAlgorithmException nsae){ }

    return hexString.toString();


}

public void popup(String msg) {
    Toast.makeText(PayMentGateWay.this, "" + msg, Toast.LENGTH_LONG).show();
}

}

Answer 1

1. You should pass your own success and failure url.(Both the url can be same). e.g: www.yourwebsitename.com/payuresponse.php
2. You can handle success or failure by getting the post parameter send by payu ($_POST['status']) to your success or failure url i.e payuresponse.php

3. Add below code as javascript code in bottom of the payuresponse.php

   function success() {

        Android.success(id,paymentId);
   
       /*u can pass more parameter too.
        Note : the number of parameter you pass from here should be      
               same you will recieve in PayMentGateWay.java class in   
               your android application*/
      }
      success();
   

   You can also do anything you want in your payuresponse.php

4. Just add anotation in your android code

@JavascriptInterface

public void success(long id, final String paymentId) {

/* u can recieve more parameter too. Note : the number of parameter you recieve here should be
same you send from payuresponse.php */

mHandler.post(new Runnable() {

public void run() {

mHandler = null;

Intent intent = new Intent(PayMentGateWay.this, MainActivity.class);

intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP |Intent.FLAG_ACTIVITY_SINGLE_TOP);

intent.putExtra("result", "success");

intent.putExtra("paymentId", paymentId);

startActivity(intent);

finish();

}

});

}

5. Hope this will work for you. Enjoy!