I'm trying to overlay a element on top of a webpage (to draw arbitrary graphics), and I've come to the point where I can stack it inside of a element on top of everything, but this prevents the user from clicking on any links/buttons/etc. Is there a way to have its content float on top of everything (it's semi-transparent, so you can still see what is behind) and have the user interact with the layer below it?
I've found a lot of information on the DOM event model, but none of it addresses the problem where the buttons and other "native" controls never seem to get the clicks in the first place.
This question is related to
javascript
html
dom
events
click
For the record an alternative approach might be to make the clickable layer the overlay: you make it semi-transparent and then place the "overlay" image behind it (somewhat counterintuitively, the "overlay" image could then be opaque). Depending on what you're trying to do, you might well be able to get the exact same visual effect (of an image and a clickable layer semi-transparently superimposed on top of each other), while avoiding clickability problems (because the "overlay" is in fact in the background).
I was having this issue when viewing my website on a phone. While I was trying to close the overlay, I was pretty much clicking on anything under the overlay. A solution that I found working for myself is to just add a tag around the entire overlay
Add pointer-events: none; to the overlay.
Original answer: My suggestion would be that you could capture the click event with the overlay, hide the overlay, then refire the click event, then display the overlay again. I'm not sure if you'd get a flicker effect though.
[Update] Exactly this problem and exactly my solution just appeared in this post: "Forwarding Mouse Events Through Layers". I know its probably a little late for the OP, but for the sake of somebody having this problem in the future, I though I would include it.
A silly hack I did was to set the height of the element to zero but overflow:visible; combining this with pointer-events:none; seems to cover all the bases.
.overlay {
height:0px;
overflow:visible;
pointer-events:none;
background:none !important;
}
In case anyone else is running in to the same problem, the only solution I could find that satisfied me was to have the canvas cover everything and then to raise the Z-index of all clickable elements. You can't draw on them, but at least they are clickable...
Generally, this isn't a great idea. Taking your scenario, if you had evil intentions, you could hide everything underneath your "overlay". Then, when a user clicks on a link they think should take them to bankofamerica.com, instead it triggers the hidden link which takes them to myevilsite.com.
That said, event bubbling works, and if it's within an application, it's not a big deal. The following code is an example. Clicking the blue area pops up an alert, even though the alert is set on the red area. Note that the orange area does NOT work, because the event will propagate through the PARENT elements, so your overlay needs to be inside whatever element you're observing the clicks on. In your scenario, you may be out of luck.
<html>
<head>
</head>
<body>
<div id="outer" style="position:absolute;height:50px;width:60px;z-index:1;background-color:red;top:5px;left:5px;" onclick="alert('outer')">
<div id="nested" style="position:absolute;height:50px;width:60px;z-index:2;background-color:blue;top:15px;left:15px;">
</div>
</div>
<div id="separate" style="position:absolute;height:50px;width:60px;z-index:3;background-color:orange;top:25px;left:25px;">
</div>
</body>
</html>
You can use an overlay with opacity set in order to the buttons/anchors in the back stay visible, but once you have that overlay over an element, you can't click it.
My team ran into this issue and resolved it very nicely.
This should resolve your problem as the events on the ".element-overlay" should bubble up to ".passthrough". If you still have problems (we did not see any so far) you can play around with the binding.
This is an enhancement to @jvenema's solution.
The nice thing about this is that
If you have any problems please let me know so I can elaborate.
How about this for IE?:
onmousedown: Hide all elements which could overlay the event. Because display:none visibility:hidden not realy works, push the overlaying div out of the screen for a fixed number of pixels. After a delay push back the overlaying div with the same number of pixels.
onmouseup: Meanwhile this is the event you like to fire.
//script
var allclickthrough=[];
function hidedivover(){
if(allclickthrough.length==0){
allclickthrough=getElementsByClassName(document.body,"clickthrough");// if so .parentNode
}
for(var i=0;i<allclickthrough.length;i++){
allclickthrough[i].style.left=parseInt(allclickthrough[i].style.left)+2000+"px";
}
setTimeout(function(){showdivover()},1000);
}
function showdivover(){
for(var i=0;i<allclickthrough.length;i++){
allclickthrough[i].style.left=parseInt(allclickthrough[i].style.left)-2000+"px";
}
}
//html
<span onmouseup="Dreck_he_got_me()">Click me if you can.</span>
<div onmousedown="hidedivover()" style="position:absolute" class="clickthrough">You'll don't get through!</div>
Source: Stackoverflow.com