Menu
I'm making a canvas webpage for animation. Strange thing is that every time I launch the webpage from double clicking the html file the canvas will almost always size incorrectly. I have post a similar question before: Canvas sizing incorrectly on loading but have no desired answer.
After extensive debugging I find out that it's the window.innerWidth that's giving me such trouble. The window.innerWidth returns 0 every time the page is launched from double clicking the html file and results in a incorrect canvas size (interestingly the canvas size is not exactly 0, but a very small one that has object to be rendered stack on top of one another), but after reloading the page (Ctrl+R) the problem no longer happens. I'm using jQuery to load the page, here is my code:
html:
<body>
<canvas id="main_canvas"></canvas>
</body>
js:
$(document).ready(function() {
var SCREEN_WIDTH = window.innerWidth-10,
SCREEN_HEIGHT = window.innerHeight-10;
if (window.innerWidth === 0) { alert("wtf? width = 0?");}
var canvas = $('canvas')[0],
context;
init(); // use $(window).load(init) does not fix the problem
function init() {
if (canvas.getContext) {
context = canvas.getContext('2d');
animate(); // draw stuff
}
else {
alert('Your browser does not support html5 canvas');
}
}
});
As you can see here, I'm already using $(docuemnt).ready(function()) to make sure things gets loaded, however from a link http://4loc.wordpress.com/2009/04/28/documentready-vs-windowload/ the author suggest that the document ready event executes already when the HTML-Document is loaded and the DOM is ready, even if all the graphics haven’t loaded yet.
On the other hand the $(window).load(function()) executes a bit later when the complete page is fully loaded, including all frames, objects and images. Therefore functions which concern images or other page contents should be placed in the load event for the window or the content tag itself. But even I use this the problem is not solved.
Maybe the js file is asking for window's width before it's loaded, but I can't find a viable solution. Can anyone help with this?
427
The read-only Window property innerWidth returns the interior width of the window in pixels. This includes the width of the vertical scroll bar, if one is present. More precisely, innerWidth returns the width of the window's layout viewport.
We can get the inner width of any element using the jQuery innerWidth() method. The innerWidth() method returns the inner width of the first matched element including padding but not border.
The Window innerHeight property is used for returning the height of a window's content area. It is a read-only property and returns a number which represents the height of the browser window's content area in pixels. Return Value: It returns a number that represents browser window's content area height in pixels.
Use an event listener that triggers on a window resize. That way you don't have to do any nonsense with trying to find when the window fully initializes. It will also make you less dependent on state which is a nice bonus.
window.addEventListener( 'resize', onWindowResize, false );
function onWindowResize() {
windowX = window.innerWidth;
windowY = window.innerHeight;
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
