The clearWatch method cancels an ongoing watchPosition call. When canceled, the watchPosition call stops retrieving updates about the current geographic location of the device.                    var watchID;          var geoLoc;          function showLocation(position) {             var latitude = position.coords.latitude;             var longitude = position.coords.longitude;             alert("Latitude : " + latitude + " Longitude: " + longitude);          }          function errorHandler(err) ... Read More

The following table describes the possible error codes returned in the PositionError object:CodeConstantDescription0UNKNOWN_ERRORThe method failed to retrieve the location of the device due to an unknown error.1PERMISSION_DENIEDThe method failed to retrieve the location of the device because the application does not have permission to use the Location Service.2POSITION_UNAVAILABLEThe location of the device could not be determined.3TIMEOUTThe method was unable to retrieve the location information within the specified maximum timeout interval.Following is a sample code, which makes use of the PositionError object. Here errorHandler method is a callback method:function errorHandler( err ) {    if (err.code == 1) {     ... Read More

Some characters are reserved in HTML5. For example, you cannot use the greater than and less than signs or angle brackets within your text because the browser could mistake them for markup.HTML5 processors must support the five special characters listed in the table that follows.SymbolDescriptionEntity NameNumber Code"quotation mark""'apostrophe''&ersand&&greater-than>>

Due to the fact that the browser doesn't need to download any font files because it is already using one, utilizing the system font of a specific operating system by default can improve efficiency. But it is true of any web-safe typeface. System fonts have the advantage of matching the fonts that the current OS uses, making them visually pleasing. There are some fonts from the Microsoft list that are also compatible with Macintosh Systems. Those are Andale Mono, Arial, Arial Black, Comic Sans MS, Courier New, Impact, Trebuchet, Verdana, Symbol, Webdings and Times New Roman The fonts ... Read More

Storing sensitive data on local machine could be dangerous and could leave a security hole. The Session Storage Data would be deleted by the browser immediately after the session gets terminated.To clear a local storage setting you would need to call localStorage.remove('key'); where 'key' is the key to the value you want to remove. If you want to clear all settings, you need to call localStorage.clear() method.                    localStorage.clear();          // Reset number of hits.          if( localStorage.hits ){         ... Read More

In HTML5, Microdata are used to nest metadata inside of already existing web page content. With this approach, machine-readable data may be easily inserted into HTML documents with a clear parsing paradigm. By using microdata, we may create our own unique elements and begin incorporating unique attributes into our web pages. Microdata is made up of a collection of name-value pairs. Items are a collection of name-value pairs, and each name-value property is referred to as a property. Regular elements are used to represent items and properties. HTML5 Microdata Global Attribute The following five global properties are introduced by ... Read More

In the following article, we are going to learn about how to create a transformation matrix with HTML5. HTML5 canvas provides methods that allow modifications directly to the transformation matrix. The transformation matrix must initially be the identity transform. It may then be adjusted using the transformation methods. Using the transform() method The transformation matrix of the current context can be changed using the transform() method.in other words, transform() method lets you scale, rotate, move, and skew the current context. Note − Only drawings that were created after the transform() method was called will be impacted by the transformation. Syntax ... Read More

The MediaStream represents synchronized streams of media. If there is no audio tracks, it returns an empty array and it will check video stream, if webcam connected, stream.getVideoTracks() returns an array of one MediaStreamTrack representing the stream from the webcam.function gotStream(stream) {    window.AudioContext = window.AudioContext || window.webkitAudioContext;    var audioContext = new AudioContext();    // Create an AudioNode from the stream    var mediaStreamSource = audioContext.createMediaStreamSource(stream);        // Connect it to destination to hear yourself    // or any other node for processing!    mediaStreamSource.connect(audioContext.destination); } navigator.getUserMedia({audio:true}, gotStream);

Web RTC introduced by World Wide Web Consortium (W3C). That supports browser-to-browser applications for voice calling, video chat, and P2P file sharing.Web RTC implements three API's as shown below −MediaStream − get access to the user's camera and microphone. RTCPeerConnection − get access to audio or video calling facility. RTCDataChannel − get access to peer-to-peer communication.Web RTC required peer-to-peer communication between browsers. This mechanism required signaling, network information, session control and media information. Web developers can choose a different mechanism to communicate between the browsers such as SIP or XMPP or any two-way communications

While creating messageChannel, it internally creates two ports to send the data and forwarded it to another browsing context.postMessage() − Post the message throw channelstart() − It sends the dataclose() − it closes the portsIn this scenario, we are sending the data from one iframe to another iframe. Here we are invoking the data in function and passing the data to DOM.Examplevar loadHandler = function(){    var mc, portMessageHandler;    mc = new MessageChannel();    window.parent.postMessage('documentAHasLoaded','http://foo.example',[mc.port2]);        portMessageHandler = function(portMsgEvent){       alert( portMsgEvent.data );    }    mc.port1.addEventListener('message', portMessageHandler, false);    mc.port1.start(); } window.addEventListener('DOMContentLoaded', loadHandler, false);