Please help me:
create clickable regions in the canvas below that I can assign onmousedown= events to. I know how to do this with invisible DIVs, but I think there is a more elegant way to do it in canvas that I don't know.
when I click one of the regions, want to pass an image name to a function so that it changes the image being displayed to another image, and then changes it back onmouseup.
if you show me just one region and one mousedown/mouseup example I can do the rest...thanks.
<!DOCTYPE HTML>
<html>
<head>
</head>
<body>
<canvas id="myCanvas" width="506" height="319" style="border:1px solid #c3c3c3;">
Your browser does not support the canvas element.
</canvas>
<script type="text/javascript">
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
var img=new Image();
img.onload = function(){
ctx.drawImage(img,0,0);
};
img.src="firstImage.gif";
</script>
/////////HERE NEED/////////
CREATE CLICKABLE REGION <region>
<region>
onmousedown=changeCanvasImage(secondImage.gif) //change image on click
onmouseup=changeCanvasImage(firstImage.gif) /change it back when done
</region>
</body>
</html>
Please help me:
create clickable regions in the canvas below that I can assign onmousedown= events to. I know how to do this with invisible DIVs, but I think there is a more elegant way to do it in canvas that I don't know.
when I click one of the regions, want to pass an image name to a function so that it changes the image being displayed to another image, and then changes it back onmouseup.
if you show me just one region and one mousedown/mouseup example I can do the rest...thanks.
<!DOCTYPE HTML>
<html>
<head>
</head>
<body>
<canvas id="myCanvas" width="506" height="319" style="border:1px solid #c3c3c3;">
Your browser does not support the canvas element.
</canvas>
<script type="text/javascript">
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
var img=new Image();
img.onload = function(){
ctx.drawImage(img,0,0);
};
img.src="firstImage.gif";
</script>
/////////HERE NEED/////////
CREATE CLICKABLE REGION <region>
<region>
onmousedown=changeCanvasImage(secondImage.gif) //change image on click
onmouseup=changeCanvasImage(firstImage.gif) /change it back when done
</region>
</body>
</html>
1 Answer
Reset to default 5The canvas element can fire events but graphical elements within the canvas cannot. To do this you'll either need to implement it yourself by detecting the position of the mouse on the canvas when it is clicked and relating the value to something in your canvas, or using one of the many canvas libraries available which will handle the detection for you.
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