我正在写一个HTML页面，以便进行一些神经心理测试。我需要图像b.png在几秒钟后消失，以便让患者绘制图像。我还需要集成触摸输入，以便平板电脑用户可以使用该测试。
<html>
<script type="text/javascript">
var canvas, ctx, flag = false,
prevX = 0,
currX = 0,
prevY = 0,
currY = 0,
dot_flag = false;
var x = "black",
y = 2;
function init() {
canvas = document.getElementById('can');
ctx = canvas.getContext("2d");
w = canvas.width;
h = canvas.height;
canvas.addEventListener("mousemove", function (e) {
findxy('move', e)
}, false);
canvas.addEventListener("mousedown", function (e) {
findxy('down', e)
}, false);
canvas.addEventListener("mouseup", function (e) {
findxy('up', e)
}, false);
canvas.addEventListener("mouseout", function (e) {
findxy('out', e)
}, false);
}
function color(obj) {
switch (obj.id) {
case "green":
x = "green";
break;
case "blue":
x = "blue";
break;
case "red":
x = "red";
break;
case "yellow":
x = "yellow";
break;
case "orange":
x = "orange";
break;
case "black":
x = "black";
break;
case "white":
x = "white";
break;
}
if (x == "white") y = 14;
else y = 2;
}
function draw() {
ctx.beginPath();
ctx.moveTo(prevX, prevY);
ctx.lineTo(currX, currY);
ctx.strokeStyle = x;
ctx.lineWidth = y;
ctx.stroke();
ctx.closePath();
}
function erase() {
var m = confirm("Want to clear");
if (m) {
ctx.clearRect(0, 0, w, h);
document.getElementById("canvasimg").style.display = "none";
}
}
function save() {
document.getElementById("canvasimg").style.border = "2px solid";
var dataURL = canvas.toDataURL();
document.getElementById("canvasimg").src = dataURL;
document.getElementById("canvasimg").style.display = "inline";
}
function findxy(res, e) {
if (res == 'down') {
prevX = currX;
prevY = currY;
currX = e.clientX - canvas.offsetLeft;
currY = e.clientY - canvas.offsetTop;
flag = true;
dot_flag = true;
if (dot_flag) {
ctx.beginPath();
ctx.fillStyle = x;
ctx.fillRect(currX, currY, 2, 2);
ctx.closePath();
dot_flag = false;
}
}
if (res == 'up' || res == "out") {
flag = false;
}
if (res == 'move') {
if (flag) {
prevX = currX;
prevY = currY;
currX = e.clientX - canvas.offsetLeft;
currY = e.clientY - canvas.offsetTop;
draw();
}
}
}
</script>
<body onload="init()">
<canvas id="can" width="800" height="800" style="position:absolute;top:10%;left:10%;border:2px solid;"></canvas>
<div style="position:absolute;top:3%;left:45%;">Gomma</div>
<div style="position:absolute;top:3%;left:50%;">Penna</div>
<div style="position:absolute;top:5%;left:45%;width:15px;height:15px;background:white;border:2px solid;" id="white" onclick="color(this)"></div>
<div style="position:absolute;top:5%;left:50%;width:17px;height:17px;background:black;" id="black" onclick="color(this)"></div>
<img id="canvasimg" style="position:absolute;top:10%;left:52%;" style="display:none;">
<input type="button" value="salva" id="btn" size="30" onclick="save()" style="position:absolute;top:2%;left:15%;">
<p>Clicca su "Inizia" per iniziare il test.</p>
<button onclick="setTimeout(salvatest, 3000); immaginetest()">Inizia</button>
<script>
function salvatest() {
document.getElementById("canvasimg").style.border = "2px solid";
var dataURL = canvas.toDataURL();
document.getElementById("canvasimg").src = dataURL;
document.getElementById("canvasimg").style.display = "inline";
}
</script>
<script>
function immaginetest() {
var src = "b.png";
show_image("b.png", 512, 800, "absolute",300,100, 1, "<alt>");
}
function show_image(src, width, height, position,left,top, zIndex, alt) {
var img = document.createElement("img");
img.src = src;
img.width = width;
img.height = height
img.style.position = position;
img.style.left = left+'px';
img.style.top = top+'px';
img.style.zIndex = zIndex;
img.alt = alt;
document.body.appendChild(img);
}
</script>
</div>
</body>
</html>我不知道如何做到这两件事，我不是一名开发人员，我是一名医生，所以我的编码知识大多是轶事，这就是我迄今为止的代码。
看看点击这里！
setTimeout(function() {
//do your job here
}, 1000)