[javascript] getContext is not a function

I'm working on making a basic web application using canvas that dynamically changes the canvas size when the window resizes. I've gotten it to work statically without any flaws but when I create an object to make it dynamically it throws an error

in chrome the error is:

Uncaught TypeError: Object [object Object] has no method 'getContext'

and in firefox it is:

this.element.getContext is not a function

I've searched the web and it seems like a common problem but none of the fixes mentioned make any difference.

The code is in question is as follows:

layer['background'] = new canvasLayer("body","background");
function canvasLayer(location,id){
    $(location).append("<canvas id='"+id+"'>unsupported browser</canvas>");
    this.element=$(id);
    this.context = this.element.getContext("2d"); //this is the line that throws the error
    this.width=$(window).width(); //change the canvas size
    this.height=$(window).height();
    $(id).width($(window).width()); //change the canvas tag size to maintain proper scale
    $(id).height($(window).height());
}

Thanks in advance.

This question is related to javascript jquery html canvas

The answer is


I recently got this error because the typo, I write 'canavas' instead of 'canvas', hope this could help someone who is searching for this.


Actually we get this error also when we create canvas in javascript as below.

document.createElement('canvas');

Here point to be noted we have to provide argument name correctly as 'canvas' not anything else.

Thanks


I got the same error because I had accidentally used <div> instead of <canvas> as the element on which I attempt to call getContext.


Alternatively you can use:

this.element=$(id)[0];

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