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Why won't my multiple rectangles draw in the canvas?
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<script src="Scripts/jquery-1.9.1.min.js"></script>
</head>
<body>
<canvas id="myCanvas" width="500" height="500" style="border:1px solid red">
<p>Your browser doesn't support canvas.</p>
</canvas>
</body>
</html>
<script type ="text/javascript">
function Shape(x, y, w, h, fill) {
this.x = x;
this.y = y;
this.w = w;
this.h = h;
this.fill = fill;
}
// get canvas element.
var elem = document.getElementById('myCanvas');
// check if context exist
if (elem.getContext) {
var myRect = [];
myRect.push(new Shape(10, 0, 25, 25, "#333"))
myRect.push(new Shape(0, 40, 39, 25, "#333"))
myRect.push(new Shape(0, 80, 100, 25, "#333"))
context = elem.getContext('2d');
for (i in myRect) {
//console.log(x);
context.fillRect(i.x, i.y, i.w, i.h)
}
//// x, y, width, height
//context.fillRect(0, 0, 50, 50);
//// x, y, width, height
//context.fillRect(75, 0, 50, 50);
}
</script>
Thanks for help.
329
The rect() method creates a rectangle. Tip: Use the stroke() or the fill() method to actually draw the rectangle on the canvas.
To draw the rectangle onto a canvas, you can use the fill() or stroke() methods. Note: To both create and render a rectangle in one step, use the fillRect() or strokeRect() methods.
Canvas Example The <canvas> element must have an id attribute so it can be referred to by JavaScript. The width and height attribute is necessary to define the size of the canvas. Tip: You can have multiple <canvas> elements on one HTML page. By default, the <canvas> element has no border and no content.
The HTML5 canvas has the potential to become a staple of the web, enjoying ubiquitous browser and platform support in addition to widespread webpage support, as nearly 90% of websites have ported to HTML5.
Ok, so you were almost there.
When you iterate round your array of rectangles, you are iterating over the array key not the objects themselves (see How to Loop through plain JavaScript object with objects as members?).
Plus, as @jimjimmy1995 pointed out, you need to set the fill using .fillStyle as .fillRect does not have a fill parameter.
This code will work:
function Shape(x, y, w, h, fill) {
this.x = x;
this.y = y;
this.w = w;
this.h = h;
this.fill = fill;
}
// get canvas element.
var elem = document.getElementById('myCanvas');
// check if context exist
if (elem.getContext) {
var myRect = [];
myRect.push(new Shape(10, 0, 25, 25, "#333"));
myRect.push(new Shape(0, 40, 39, 25, "#333"));
myRect.push(new Shape(0, 80, 100, 25, "#333"));
context = elem.getContext('2d');
for (var i in myRect) {
oRec = myRect[i];
context.fillStyle = oRec.fill;
context.fillRect(oRec.x, oRec.y, oRec.w, oRec.h);
}
}
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