How can I fetch data from a web server in an android application? -

i want retrieve data web server in android application, , don't know begin. should use web services?

i recommend these tutorials:

connect android php , mysql, json in android , php , mysqli

i used these tutorials , managed trying working without difficulty.

between them describe each step in how attempting @ each stage, android application, database , web server side , has information included can process , use received information

the thing add connect android php , mysql tutorial makes use of mysql_ in php deprecated. better use mysqli why included third link.

the basic outline of want this:

1) in android app make request server php script using class this:

import java.io.bufferedreader; import java.io.ioexception; import java.io.inputstream; import java.io.inputstreamreader; import java.io.unsupportedencodingexception; import java.util.list;  import org.apache.http.httpentity; import org.apache.http.httpresponse; import org.apache.http.namevaluepair; import org.apache.http.client.clientprotocolexception; import org.apache.http.client.entity.urlencodedformentity; import org.apache.http.client.methods.httpget; import org.apache.http.client.methods.httppost; import org.apache.http.client.utils.urlencodedutils; import org.apache.http.impl.client.defaulthttpclient; import org.json.jsonexception; import org.json.jsonobject;  import android.util.log;  public class jsonparser {      // response http request     static inputstream httpresponsestream = null;     // json response string create json object     static string jsonstring = "";      // method issue http request, parse json result , return json object     public jsonobject makehttprequest(string url, string method,             list<namevaluepair> params) {          try {             // http client             defaulthttpclient httpclient = new defaulthttpclient();              // if required http method post             if (method == "post") {                 // create http post object                 httppost httppost = new httppost(url);                 // encode passed parameters http request                 httppost.setentity(new urlencodedformentity(params));                 // execute request , fetch http response                 httpresponse httpresponse = httpclient.execute(httppost);                 // extract result response                 httpentity httpentity = httpresponse.getentity();                 // open result input stream parsing                 httpresponsestream = httpentity.getcontent();             }             // else if             else if (method == "get") {                 // format parameters correctly http transmission                 string paramstring = urlencodedutils.format(params, "utf-8");                 // add parameters url in format                 url += "?" + paramstring;                 // execute request                 httpget httpget = new httpget(url);                 // execute request , fetch http response                 httpresponse httpresponse = httpclient.execute(httpget);                 // extract result response                 httpentity httpentity = httpresponse.getentity();                 // open result input stream parsing                 httpresponsestream = httpentity.getcontent();             }             // catch possible exceptions         } catch (unsupportedencodingexception e) {             e.printstacktrace();         } catch (clientprotocolexception e) {             e.printstacktrace();         } catch (ioexception e) {             e.printstacktrace();         }          try {             // create buffered reader httpresponcestream             bufferedreader httpresponsereader = new bufferedreader(                     new inputstreamreader(httpresponsestream, "iso-8859-1"), 8);             // string hold current line httpresponsereader             string line = null;             // clear jsonstring             jsonstring = "";             // while there still more response read             while ((line = httpresponsereader.readline()) != null) {                 // add line jsonstring                 jsonstring += (line + "\n");             }             // close response stream             httpresponsestream.close();         } catch (exception e) {             log.e("buffer error", "error converting result " + e.tostring());         }          try {             // create jsonobject jsonstring , return             return new jsonobject(jsonstring);         } catch (jsonexception e) {             log.e("json parser", "error parsing data " + e.tostring());             // return null if in error             return null;         }     } } 

which handles communication, opens connection , receives json string processes json object.

2) in php server, open mysqli connection sql database, run mysqli->query() , following result:

if (mysqli_num_rows($result) > 0) {         // looping through results         $response["apps"] = array();          while ($row = mysqli_fetch_array($result)) {              $apps = array();              $apps["name"] = $row["name"];             $apps["package"] = $row["package"];             $apps["version"] = $row["version"];             $apps["dateversion"] = $row["dateversion"];             $apps["sdkver"] = $row["sdkver"];             $apps["pathroot"] = $row["pathroot"];             $apps["rootname"] = $row["rootname"];             $apps["apkmd5"] = $row["apkmd5"];             $apps["extraapkmd5"] = $row["extraapkmd5"];             $apps["instructionsmd5"] = $row["instructionsmd5"];             $apps["assetsmd5"] = $row["assetsmd5"];             $apps["root"] = $row["root"];             $apps["current"] = $row["current"];              // push single product final response array             array_push($response["apps"], $apps);         }         // success         $response["success"] = 1;          // echoing json response         echo json_encode($response); 

this iterates through database response , encodes json string sent android app can process it.

how create explained in tutorials linked