關于isPointInPath(x,y)
老師，我調試了這個代碼，為什么我的context.isPointInPath(x,y)輸出的值總是false，chorme，firefox，ie都是，還有用fillRect()繪制的矩形，判斷其內部的點也是返回false，這是為什么啊？
4 回答
舉報
0/150
提交
取消
老師，我調試了這個代碼，為什么我的context.isPointInPath(x,y)輸出的值總是false，chorme，firefox，ie都是，還有用fillRect()繪制的矩形，判斷其內部的點也是返回false，這是為什么啊？
2016-04-13
舉報
2016-04-28
看到了。。。。。。。
2016-04-27
幫忙看看哪里錯了
2016-04-27
<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<title>canvas偽類</title>
</head>
<body>
<canvas class="" id="canvas" width=''></canvas>
<script>
var balls =[];
var canvas = document.getElementById('canvas');
var context = canvas.getContext("2d");
window.onload = function(){
canvas.width =800;
canvas.height =800;
context.fillStyle ="#085";
for(var i = 0; i<10;i++){
var aBall = {
x:Math.random()*canvas.width,
x:Math.random()*canvas.height,
r:Math.random()*50+20};
balls[i] = aBall;
}
draw();
canvas.addEventListener("mousemove",detect)
}
function draw(x,y){
context.clearRect(0,0,canvas.width,canvas.height);
for(var i = 0 ;i<balls.length;i++){
context.beginPath();
context.arc(balls[i].x,balls[i].y,balls[i].r,0,Math.PI*2);
if( context.isPointInPath(x,y)){
context.fillStyle="red";
}else{
context.fillStyle="#058";
}
context.fill();
}
}
function detect(event) {
var x = event.clientX - canvas.getBoundingClientRect().left;
var y = event.clientY - canvas.getBoundingClientRect().top;
draw(x,y);
}
</script>
2016-04-16
no node,no answer.