While i draw image to canvas, loading gif won't animate on phonegap/cordova, the code looks like this:
.hide{
display:none;
}
.absolute{
position:absolute;
}
<div id="loading" class="hide absolute">
<img src="loading.gif"/>
</div>
var drawCanvas = function (img) {
var element = document.getElementById('loading')
canvas = document.getElementById('canvas')
context = canvas.getContext('2d');
element.classList.remove('hide');
setTimeout(function () {
context.drawImage(img,0,0);
}, 0);
element.classList.add('hide');
};
I also tried replacing animated gif with css animation, but its exactly the same, the browser refuses to animate anything while drawing the canvas
Any help appreciated
NB: it happens not on desktop but only in cordova/phonegap, i guess the cause is lack of hardware performance on mobile (tested on Android tablet 4.1)
Try increasing the delay. A delay of 0 doesn't really help much as there is not enough time for some browser to do anything else. Give a frame or so. Also continue from inside the callback as it is asynchronous:
setTimeout(function () {
context.drawImage(img,0,0);
element.classList.add('hide'); // you'll probably like this to be here
}, 17); // 17ms ~16.667ms as one frame takes @ 60 fps
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