# SystemInfo Service API example

This section presents the full source code of a working sample widget for the SystemInfo Service. You can download the `wgz` package for this widget from section Example widgets.

For general information about creating widgets, see section Widget component files.

For widget development and debugging purposes, this example writes its output to `c:\data\jslog_widget.log` using `console.info`. For instructions on how to enable logging in the Web browser for S60, see section JavaScript console.

### Info.plist

    <?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE plist PUBLIC "-//Nokia//DTD PLIST 1.0//EN" "http://www.nokia.com/NOKIA_COM_1/DTDs/plist-1.0.dtd">
    <plist version="1.0">
    <dict>
      <key>DisplayName</key>
      <string>SysInfoSample</string>
      <key>Identifier</key>
      <string>com.nokia.widget.sapi.sysinfo.sample</string>
      <key>Version</key>
      <string>1.0</string>
      <key>MainHTML</key>
      <string>sysinfo-sample.html</string>
    </dict>
    </plist>

### sysInfo-sample.html

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <script type="text/javascript" src="js/common.js"></script>
        <script type="text/javascript" src="js/sysinfo-sample.js"></script>
      </head>
      <body id='docBody' bgcolor="#ddeeff" onload="setup()" style=width:100%;height:100%;>
        <form name="frm">
          <h3>Sysinfo API Sample Widget</h3>
          <input type="button" onclick="getSysInfo('img1')" value="GetSysInfo"><img id="img1" src="pic/blank.png" width="25" height="25" align="center"><br>
          <input type="button" onclick="setSysInfo('img2')" value="SetSysInfo"><img id="img2" src="pic/blank.png" width="25" height="25" align="center"><br>
          <input type="button" onclick="getSysInfoAsync('img3')" value="GetSysInfoAsync"><img id="img3" src="pic/blank.png" width="25" height="25" align="center"><br>
          <input type="button" onclick="getNotification('img4')" value="GetNotification"><img id="img4" src="pic/blank.png" width="25" height="25" align="center"><br>
          <input type="button" onclick="cancelGetSysInfoAsync('img5')" value="CancelGetSysInfoAsync"><img id="img5" src="pic/blank.png" width="25" height="25" align="center"><hr>
          <div class='sysinfo' id='sysinfo' bgcolor="#ddeeff" style=width:100%;height:100%;overflow:auto></div>
        </form>
      </body>
    </html>

### common.js

    // common.js
    //
    // This file contains some utility functions

    // Check the error code and show the information to users
    function checkError(message, resultList, divId, imgId)
    {
      var errCode = resultList.ErrorCode;
      var msg = "";

      if (errCode) {
        msg = message + "<BR>" + "Failed Error: " + errCode + "<BR>";
        if(resultList.ErrorMessage != undefined)
          msg += "Error Message: " + resultList.ErrorMessage;
        showIMG(imgId,"no");
      } else {
        showIMG(imgId,"yes");
      }

      //print error message
      if(divId != null && divId != undefined)
        document.getElementById(divId).innerHTML = msg;
      console.info(msg);

      return errCode;
    }

    // Build the message by reading a iteratorable list in a recursive manner
    function showIterableList(iterator)
    {
      var msg = "";
      try
      {
        iterator.reset();
        var item;
        while (( item = iterator.getNext()) != undefined ){
          msg += showObject( item );
        }
      }
      catch(e)
      {
        alert('<showIterableList> ' + e);
      }
      return msg;
    }

    // Build the message by reading a JS object in a recursive manner
    function showObject( obj )
    {
      var txt = "";
      try {
        if ( typeof obj != 'object' )
          return "" + obj + '<BR/>';
        else {
          for(var key in obj) {
            txt +=  key + ":";
            txt += showObject( obj[key] );
            txt += '<BR/>';
          }
          txt += '<BR/>';
        }
      }
      catch (e)
      {
        alert("showObject: " + e);
      }
      return txt;
    }

    // Show the image to indicate the test result
    function showIMG(imgId, isOK)
    {
      if(imgId == null || imgId == undefined)
        return;

      if(isOK == "yes")
        document.getElementById(imgId).src = "pic/yes.png";
      else if(isOK == "no")
        document.getElementById(imgId).src = "pic/no.png";
      else
        document.getElementById(imgId).src = "pic/blank.png";
    }

    // Show elements in object by using 'alert'
    function testObject(obj)
    {
      var msg = "";
      for(var key in obj) {
        msg = msg + ":" + key + "=" + obj[key];
      }
      alert(msg);
    }

    // Test whether the input is numeric
    function IsNumeric(sText)
    {
      var ValidChars = "0123456789.";
      var IsNumber=true;
      var Char;

      for (i = 0; i < sText.length && IsNumber == true; i++)
      {
        Char = sText.charAt(i);
        if (ValidChars.indexOf(Char) == -1)
        {
          IsNumber = false;
        }
      }
      return IsNumber;
    }

### sysInfo-sample.js

    // sysinfo-sample.js
    //
    // In this sample system information will be listed and changed; The
    // notification will be send when the system info changes; Also,
    // async operation will be canceled.
    //

    //SAPI Error Codes
    // 0    - Success
    // 1000 - InvalidServiceArgument
    // 1001 - UnknownArgumentName
    // 1002 - BadArgumentType
    // 1003 - MissingArgument
    // 1004 - ServiceNotSupported
    // 1005 - ServiceInUse
    // 1006 - ServiceNotReady
    // 1007 - NoMemory
    // 1008 - HardwareNotAvailable
    // 1009 - ServerBusy
    // 1010 - EntryExists
    // 1011 - AccessDenied
    // 1012 - NotFound
    // 1013 - UnknownFormat
    // 1014 - GeneralError
    // 1015 - CancelSuccess
    // 1016 - ServiceTimedOut
    // 1017 - PathNotFound

    // Declare the service object
    var so;

    // imgid for callback1 function
    var imgid_callback1;

    // imgid for callback2 function
    var imgid_callback2;

    // imgid for callback3 function
    var imgid_callback3;

    // id of the div used to display information
    const DIV_ID = 'sysinfo';

    // Called from onload()
    function setup()
    {
      try {
        so = device.getServiceObject("Service.SysInfo", "ISysInfo");
        console.info("setup: so: %s", so);
      }
      catch (e) {
        alert('<setup> ' +e);
      }
    }

    //Get SysInfo
    function getSysInfo(imgId)
    {
      // get the entity
      var entity = prompt("Please enter the Entry", "General");
      var key = prompt("Please enter the Key", "VibraActive");
      var criteria = new Object();
      criteria.Entity = entity;
      criteria.Key = key;

      try {
        var result = so.ISysInfo.GetInfo(criteria);
        if(!checkError("ISysInfo::getSysInfo",result,DIV_ID,imgId)) {
          document.getElementById(DIV_ID).innerHTML = showObject(result.ReturnValue);
        }
      }
      catch (e) {
        showIMG(imgId,"no");
        alert ("getSysInfo: " + e);
      }
    }

    //Set SysInfo
    function setSysInfo(imgId)
    {
      // get the entity
      var entity = prompt("Please enter the Entry", "General");
      var key = prompt("Please enter the Key", "VibraActive");
      var vals = prompt("Please enter the new Value", 0);

      var systemData = new Object();
      if(IsNumeric(vals)) {
        systemData.Status = parseInt(vals);
      } else {
        systemData.StringData = vals;
      }

      var criteria = new Object();
      criteria.Entity = entity;
      criteria.Key = key;
      criteria.SystemData = systemData;

      try {
        var result = so.ISysInfo.SetInfo(criteria);
        checkError("ISysInfo::setSysInfo",result,DIV_ID,imgId);
      }
      catch (e) {
        showIMG(imgId,"no");
        alert ("setSysInfo: " + e);
      }
    }

    //Get SysInfo
    function getSysInfoAsync(imgId)
    {
      // get the entity
      var entity = prompt("Please enter the Entry", "Network");
      var key = prompt("Please enter the Key", "HomeNetwork");

      var criteria = new Object();
      criteria.Entity = entity;
      criteria.Key = key;

      try {
        imgid_callback1 = imgId;
        var result = so.ISysInfo.GetInfo(criteria, callback1);
        if(!checkError("ISysInfo::getSysInfoAsync",result,DIV_ID,imgId))
          showIMG(imgId, "");
      }
      catch (e) {
        showIMG(imgId,"no");
        alert ("getSysInfoAsync: " + e);
      }
    }

    // set callback function for notification
    function getNotification(imgId)
    {
      // get the entity
      var entity = prompt("Please enter the Entry", "General");
      var key = prompt("Please enter the Key", "VibraActive");

      var criteria = new Object();
      criteria.Entity = entity;
      criteria.Key = key;

      try {
        imgid_callback2 = imgId;
        var result = so.ISysInfo.GetNotification(criteria,callback2);
        if(!checkError("ISysInfo::getNotification",result,DIV_ID,imgId))
          showIMG(imgId, "");
      }
      catch (e) {
        showIMG(imgId,"no");
        alert ("setSysInfo: " + e);
      }
    }

    //Ccancel SysInfo
    function cancelGetSysInfoAsync(imgId)
    {
      // get the entity
      var entity = prompt("Please enter the Entry", "Network");
      var key = prompt("Please enter the Key", "HomeNetwork");

      var criteria = new Object();
      criteria.Entity = entity;
      criteria.Key = key;

      try {
        imgid_callback3 = imgId;
        var result = so.ISysInfo.GetInfo(criteria, callback3);
        if(!checkError("ISysInfo::cancelGetSysInfoAsync",result,DIV_ID,imgId)){
          var criteria2 = new Object();
          criteria2.TransactionID = result.TransactionID;
          var cresult = so.ISysInfo.Cancel(criteria2);
          checkError("ISysInfo::cancelGetSysInfoAsync",cresult,DIV_ID,imgId);
        }
      }
      catch (e) {
        showIMG(imgId,"no");
        alert ("cancelGetSysInfoAsync: " + e);
      }
    }

    // This is the asynchronous callback handler
    function callback1(transId, eventCode, result)
    {
      console.info("callback1: transId: %d  eventCode: %d result.ErrorCode: %d", transId, eventCode, result.ErrorCode);
      if(!checkError("callback1::getSysInfoAsync",result,DIV_ID,imgid_callback1)) {
        document.getElementById(DIV_ID).innerHTML = showObject(result.ReturnValue);
      }
    }

    // This is the asynchronous callback handler
    function callback2(transId, eventCode, result)
    {
      console.info("callback2: transId: %d  eventCode: %d result.ErrorCode: %d", transId, eventCode, result.ErrorCode);
      if(!checkError("callback2::getNotification",result,DIV_ID,imgid_callback2)) {
        document.getElementById(DIV_ID).innerHTML = "Got Notification!Following settings changed!\n" + showObject(result.ReturnValue);
      }
    }

    // This is the asynchronous callback handler
    function callback3(transId, eventCode, result)
    {
      console.info("callback3: transId: %d  eventCode: %d result.ErrorCode: %d", transId, eventCode, result.ErrorCode);
      if(!checkError("callback3::getNotification",result,DIV_ID,imgid_callback3)) {
        document.getElementById(DIV_ID).innerHTML = showObject(result.ReturnValue);
      }
    }