Question

I have multiple JavaScript draggable DIV windows. When clicking a DIV, I want the window to get the highest z-index value. I’ve made a solution by adding/removing classes to the element in focus, BUT, I would like the windows to keep their “layer” -order (as if the entire DIV window node was re-appended to the DOM when being clicked).

Let’s say there are five DIV’s in the DOM. div1, div2, div3, div4 and div5. -div5 is closest to the front and div1 is in the back and so on.

When clicking div1, -div1 will get focus and put to front, setting div5 back one step. Then clicking div3, -div3 gets closest to front and div1 and div5 are put back one step like this: div2, div4, div5, div1, div3.

Answer 1

If you’d like to do this without re-appending the element, my solution when I wrote something similar a while back was to keep track of the maximum z-index. Every time a window is brought forward, the maximum z-index is incremented and the element’s z-index is set to the new value. Of course, if someone messes with the windows enough, they might end up having very large z-index values, so this isn’t always the best solution.

var maximumZIndex = 1;
var bringForward = function (element) {
    maximumZIndex += 1;
    element.style.zIndex = maximumZIndex;
}