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POHTML5 Canvas (Drawing (Rectangle) Keeps Disappearing)
 

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    <p>how's it going? </p> <p>Recently, with the help given from this site, I've learned how to draw a rectangle on an HTML5 canvas at the click of the button... that's not the problem:) The is problem this... unfortunately, every time I click on the canvas to make a new rectangle, the old rectangle disappears (or is instantly erased). It also didn't work at all when I tried to use it on my iPod... why:(?</p> <hr> <p>Here's my code: </p> <hr> <p>JAVASCRIPT: </p> <pre><code> // "Rectangle" Button function rect() { var canvas = document.getElementById('canvasSignature'), ctx = canvas.getContext('2d'), rect = {}, drag = false; function init() { canvas.addEventListener('mousedown', mouseDown, false); canvas.addEventListener('mouseup', mouseUp, false); canvas.addEventListener('mousemove', mouseMove, false); } function mouseDown(e) { rect.startX = e.pageX - this.offsetLeft; rect.startY = e.pageY - this.offsetTop; drag = true; } function mouseUp() { drag = false; } function mouseMove(e) { if (drag) { rect.w = (e.pageX - this.offsetLeft) - rect.startX; rect.h = (e.pageY - this.offsetTop) - rect.startY ; ctx.clearRect(0,0,canvas.width,canvas.height); draw(); } } function draw() { ctx.fillRect(rect.startX, rect.startY, rect.w, rect.h); } init(); } </code></pre> <hr> <p>HTML5:</p> <pre><code>&lt;div id="canvasDiv"&gt; &lt;canvas id="canvasSignature" width="580px" height="788px" style="border:2px solid #000; background: #FFF;"&gt;&lt;/canvas&gt; &lt;/div&gt; &lt;div id="rect"&gt; &lt;p&gt;&lt;button onclick="rect();"&gt;Rectangle&lt;/button&gt;&lt;/p&gt; &lt;/div&gt; </code></pre> <hr> <p>Any help at all would be greatly appreciated:) </p>
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