我试图制作它,这样当鼠标在var play设置的边界内时,它会改变图像 . 我使用了与用于在点击时更改图像相同的方法,但是mouseover和mouseout不想在这里工作 .
var play = {
x: 650,
y: 360,
width: 200,
height: 100
}
var playUpButton = new Image();
playUpButton.src = "images/PlayUp.png";
var playDownButton = new Image();
playDownButton.src = "images/PlayDown.png";
var playHovering = false;
thisCanvas.addEventListener('click', checkPlay);
thisCanvas.addEventListener('mouseover', hoverPlay, false);
thisCanvas.addEventListener('mouseout', hoverPlay, false);
function seen_move(e)
{
var bounding_box = thisCanvas.getBoundingClientRect();
mouseX = ((e.clientX-bounding_box.left) *(thisCanvas.width/bounding_box.width));
mouseY = ((e.clientY-bounding_box.top) * (thisCanvas.height/bounding_box.height));
}
function draw_start()
{
context.drawImage(menubg, menubg.x, menubg.y, menubg.width, menubg.height);
if(playHovering)
{
context.drawImage(playDownButton, play.x, play.y, play.width, play.height);
}
}
function mouseInArea(top, right, bottom, left)
{
if(mouseX >= left && mouseX < right && mouseY >= top && mouseY < bottom)
{
return true;
}
else
{
return false;
}
}
function hoverPlay()
{
if(mouseInArea(play.y, play.x + play.width, play.y + play.height, play.x))
{
console.log("Hovering");
if(playHovering)
{
playHovering = false;
}
else
{
playHovering = true;
}
}
}
2 回答
您的代码中似乎缺少以下内容 .
函数checkPlay似乎也缺失了 .
看看这些文章:http://www.html5canvastutorials.com/advanced/html5-canvas-mouse-coordinates/ http://www.informit.com/articles/article.aspx?p=1903884&seqNum=6
您必须调用
function seen_move(e)
才能获得鼠标位置 .顺便说一句,我对
seen_move
中的额外代码感到困惑 . 我'm guessing you'重新设置相对于边界框的鼠标位置 . 我只是提到它,以防这也是一个问题: