This section presents the full source code of a working sample widget
for the Sensor Service.
You can download the wgz package for this widget from
section Introduction to STEW.
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.
<?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>SensorSample</string> <key>Identifier</key> <string>com.nokia.widget.sapi.sensor.sample</string> <key>Version</key> <string>1.0</string> <key>MainHTML</key> <string>sensor-sample.html</string> </dict> </plist>
<!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/sensor-sample.js" charset="utf-8"></script>
</head>
<body onload='setup()' bgcolor="#ddeeff">
<form name="frm">
<h3>Sapi Sensor Sample Widget</h3>
<input type="button" onclick="findSensorChannel('img1')" value="FindSensorChannel"><img id="img1" src="pic/blank.png" width="25" height="25" align="center"><br>
<input type="button" onclick="getChannelProperty('img2')" value="GetChannelProperty"><img id="img2" src="pic/blank.png" width="25" height="25" align="center"><br>
<input type="button" onclick="setChannelProperty('img3')" value="RegisterForNotification"><img id="img5" src="pic/blank.png" width="25" height="25" align="center"><br>
<input type="button" onclick="stopReceivingNotification('img6')" value="Cancel"><img id="img6" src="pic/blank.png" width="25" height="25" align="center"><hr>
<div class='sensor' id='sensor' bgcolor="#ddeeff" style=width:100%;height:100%;overflow:auto></div>
</form>
</body>
</html>
// 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;
}
// sensor-sample.js
//
// In this sample the sensor will be found, get and set;
// 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
// Usage:
// 1. Call FindSensorChannel (input searchCriterion) - this call obtains a list of maps.The list can be fetched using the key : ReturnValue
// 2. From the list you need to fetch one ChannelInfo as a map.The fetching depends on how the runtime fetches items from an CLiwDefaultList.
// 3. It is this ChannelInfo map that needs to be supplied to all the other APIs that follow.
// Declare the service object
var so;
// imgid for callback1 function
var imgid_callback1;
// id of the div used to display information
const DIV_ID = 'sensor';
// transaction id
var transactionID;
// Called from onload()
function setup()
{
try {
so = device.getServiceObject("Service.Sensor", "ISensor");
console.info("setup: so: %s", so);
}
catch (e) {
alert('<setup> ' +e);
}
}
//FindSensorChannel - searches and list available sensor channels.
function findSensorChannel(imgId)
{
var criteria = new Object();
criteria.SearchCriterion = "Rotation";
try
{
var result = so.ISensor.FindSensorChannel(criteria);
if(!checkError("ISensor::findSensorChannel",result,DIV_ID,imgId)) {
document.getElementById(DIV_ID).innerHTML = showIterableList(result.ReturnValue);
}
}
catch (e)
{
showIMG(imgId,"no");
alert ("findSensorChannel: " + e);
}
}
// GetChannelProperty
function getChannelProperty(imgId)
{
var channelInfoMap = new Object();
channelInfoMap.ChannelId = 1;
channelInfoMap.ContextType = 0; // 0-not defined; 1- to measure pressure, ...
channelInfoMap.Quantity = 0;
channelInfoMap.ChannelType = 0 ;
var criteria = new Object();
criteria.PropertyId = "Description";
criteria.ChannelInfoMap = channelInfoMap;
try
{
var result = so.ISensor.GetChannelProperty(criteria);
if(!checkError("ISensor::getChannelProperty",result,DIV_ID,imgId)) {
document.getElementById(DIV_ID).innerHTML = showIterableList(result.ReturnValue);
}
}
catch (e)
{
showIMG(imgId,"no");
alert ("getChannelProperty: " + e);
}
}
// RegisterForNotification - register to receive
// notification about channel data.
function registerForNotification(imgId)
{
var channelInfoMap = new Object();
channelInfoMap.ChannelId = 1;
channelInfoMap.ContextType = 0; // 0-not defined; 1- to measure pressure, ...
channelInfoMap.Quantity = 0;
channelInfoMap.ChannelType = 0 ;
var criteria = new Object();
criteria.ListeningType = "ChannelData";
criteria.ChannelInfoMap = channelInfoMap;
try
{
imgid_callback1 = imgId
var result = so.ISensor.RegisterForNotification(criteria, callback1);
transactionID = result.TransactionID;
if(!checkError("ISensor::registerForNotification",result,DIV_ID,imgId)){
showIMG(imgId,"");
}
}
catch (e)
{
showIMG(imgId,"no");
alert ("registerForNotification: " + e);
}
}
//Cancel Notification
function Cancel(imgId)
{
var criteria = new Object();
criteria.TransactionID = transactionID;
try
{
var result = so.ISensor.Cancel(criteria);
checkError("ISensor::Cancel",result,DIV_ID,imgId)
}
catch (e)
{
showIMG(imgId,"no");
alert ("Cancel: " + 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("ISensor::registerForNotification",result,DIV_ID,imgid_callback1)) {
document.getElementById(DIV_ID).innerHTML = "Channel Property changes";
}
}