var canvas = document.getElementsByTagName("canvas")[0]; var but1 = document.getElementById('submit'); function Resize() { canvas.style.margin = "10px"; canvas.width = window.innerWidth - 20; canvas.height = window.innerHeight - 70; } window.addEventListener("load", Resize, false); window.addEventListener("resize", Resize, false); but1.onclick = function () { var ctx = canvas.getContext("2d"); ctx.clearRect(0, 0, window.innerWidth, window.innerHeight); for (var i = 0; i < 10; i++) { for (var j = 0; j < 20; j++) { var t = new BlinkStatus(5 + 35 * i, 5 + 20 * j, 30, 15); t.BuildDefault(); t.status = Math.floor(Math.random() * 4); t.Print(ctx); } } }