Front End Scripts Articles - Page 32 of 60

For full page drag and drop files, try the following code:var myDrop = document.getElementById('dropZone'); function displayDropZone() {    myDrop.style.visibility = "visible"; } function hideDropZone() {    myDrop.style.visibility = "hidden"; } function allowDrag(ev) {    if (true) {       ev.dataTransfer.dropEffect = 'copy';       ev.preventDefault();    } } function handleDrop(ev) {    ev.preventDefault();    hideDropZone();    alert('This is Drop!'); } window.addEventListener('dragenter', function(ev) {    displayDropZone(); }); myDrop.addEventListener('dragenter', allowDrag); myDrop.addEventListener('dragover', allowDrag); myDrop.addEventListener('dragleave', function(e) {    hideDropZone(); }); myDrop.addEventListener('drop', handleDrop);

To make a element to be recognized by Safari:main {    display: block;    width: 800px;    height: 800px;    background-color: #0C0; }You need to focus on:main {    display: block; }

To solve the issue for HTML5 meta viewport, you can any of the following fix:You can also try this:Let us say you have a site width of 100px, then it won’t display the whole page, withinitial-scale = 1

To send a file and parameters within the same XMLHttpRequest:var myForm = new FormData(); myForm.append('param1', 'demo'); myForm.append('param2', 6767); myForm.append('myDir', 'public-data'); myForm.append('demofile', file); xhr.send(myForm);

To enhance HTML5 canvas performance:Image smoothing should be disabledRender in half resolutionUse drawImage() to update main canvas You need to use integer coordinates and sizesUsage of requestAnimationFrame() You need to use while loops as often as you can

To draw image onto the canvas, use the HTML5 drawImage() method:                    function drawShape(){             // get the canvas element using the DOM             var canvas = document.getElementById('mycanvas');                       // Make sure we don't execute when canvas isn't supported             if (canvas.getContext){                // use getContext to use the canvas for drawing                var ctx = canvas.getContext('2d');                // Draw shapes                var img = new Image();                img.src = '/images/backdrop.jpg';                img.onload = function(){                   ctx.drawImage(img,0,0);                   ctx.beginPath();                   ctx.moveTo(30,96);                   ctx.lineTo(70,66);                   ctx.lineTo(103,76);                   ctx.lineTo(170,15);                   ctx.stroke();                }             } else {                alert('You need Safari or Firefox 1.5+ to see this demo.');             }          }                        

You need to try the following to take photo from webcam using HTML5:Declare variablesvar streaming = false,    video = document.querySelector('#video'), canvas = document.querySelector('#canvas'),    photo = document.querySelector('#photo'),    startbutton = document.querySelector('#startbutton'),    width = 320,    height = 0;Using getUserMedianavigator.getMedia = ( navigator.getUserMedia ||                 navigator.webkitGetUserMedia ||                   navigator.mozGetUserMedia ||                    navigator.msGetUserMedia);

To solve the loading issues in the element, you need to set cross-origin to “anonymous”:You can also try another fix also.This can be due to missing of Access-Control-Allow-Headers response header with the list of HTTP headers that match the list passed in Access-Control-Request-Headers request header.

Try the following code to add a stop button to your audio in HTML5:function displayStopBtn() {    var myPlayer = document.getElementsByTagName('audio')[0];    myPlayer.pause();    myPlayer.currentTime = 0; }You can also include jQuery:$("#stopButton").click(function () {    audio.pause();    audio.currentTime = 0; });

The validator considers the following table as valid:                 Example                                                                                                                                                My                            Table