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POJavascript canvas not working
 

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  1. POJavascript canvas not working
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    <p>I am trying to create a javascript canvas using an external javascript file. but for some reason when I run my code instead of getting the canvas I have coded I just get a white block. The chrome debugger finds no problem with my code so I am lost any help would be greatly appriciated.</p> <p>This is my index file</p> <pre><code>&lt;!doctype html&gt; &lt;html&gt; &lt;head&gt; &lt;title&gt;Lab1&lt;/title&gt; &lt;script type="text/javascript" src="javascript/canvas.js"&gt;&lt;/script&gt; &lt;/head&gt; &lt;body&gt; &lt;canvas id="canvas" width="800" height="600"&gt; Your browser does not support the canvas tag &lt;/canvas&gt; &lt;p&gt;This is a simple 'Hello World' lab tutorial using the HTML5 canvas.&lt;/p&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>And this is my javascript file</p> <pre><code>// check to see if the browser supports // the addEventListener function if(window.addEventListener) { window.addEventListener ( 'Load', // this is the load event onLoad, // this is the event handler we are going to write false // useCapture boolean value ); } // the window load event handler function onLoad() { var canvas; var context; // this function will initialise our variables function initialise() { // Find the canvas element using its id attribute. canvas = document.getElementById('canvas'); // if it couldn't be found if (!canvas) { // make a message box pop up with the error. alert('Error: I cannot find the canvas element!'); return; } // check if there is a getContext function if (!canvas.getContext) { // make a message box pop up with the error. alert('Error: no canvas.getContext!'); return; } // Get the 2D canvas context. context = canvas.getContext('2d'); if (!context) { alert('Error: failed to getContext!'); return; } } // this function will actually draw on the canvas function draw() { // set the draw fill style colour to black context.fillStyle = "#000000"; // fill the canvas with black context.fillRect(0,0,canvas.width,canvas.height); // choose a font for our message context.font = "40pt Calibri"; // set the draw fill colour to white context.fillStyle = "#ffffff"; // draw the text at the specified position context.fillText("Hello World!", 150, canvas.height); } // call the initialise and draw functions initialise(); draw(); } </code></pre>
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