I need to include multiple images in a canvas. I want to load them dynamically via a for-loop.

I tried a lot but in the best case only the last image is displayed. I check this tread but I still get only the last image.

For explanation, here's my latest code(basically the one from the other post):

 for (var i = 0; i <= max; i++)
{
    thisWidth = 250;
    thisHeight = 0;
    imgSrc = "photo_"+i+".jpg";
    letterImg = new Image();
    letterImg.onload = function() {
        context.drawImage(letterImg,thisWidth*i,thisHeight);
    }
    letterImg.src = imgSrc;
}

Any ideas?