How do I get the element being edited?

问题:

I'm developing a webapp, and I have a problem with the JavaScript.

The following is a simplified version of the HTML causing the problem. I have some nested contenteditable divs (I replaced the real content with placeholder text):

<div contenteditable="true" id="div1">
    text
    <div contenteditable="inherit" id="div2">
        text
        <div contenteditable="inherit" id="div3">
            text
        </div>
        text
    </div>
    text
</div>

I want to get the element that's selected (being edited by the user) via JavaScript, but so far I haven't found a way to do it (successfully).

---

What I have tried and why it doesn't work:

I have tried using document.activeElement, which is supposed to return whichever element is in focus. Normally this works, but it doesn't produce the desired result when working with nested contenteditable elements. Instead of returning the element that's being edited by the user, it returns the uppermost contenteditable ancestor.

For instance, if div2 is selected/being edited, document.activeElement returns div1. If div3 was selected/being edited, document.activeElement also returns div1.

So I guess document.activeElement is not the right way to go about this.

---

How do I get the most specific element that's being edited, not its uppermost contenteditable ancestor?

回答1:

I did it by inserting a dummy element at the caret position and finding it's direct parent.

function getActiveDiv() {
    var sel = window.getSelection();
    var range = sel.getRangeAt(0);
    var node = document.createElement('span');
    range.insertNode(node);
    range = range.cloneRange();
    range.selectNodeContents(node);
    range.collapse(false);
    sel.removeAllRanges();
    sel.addRange(range);
    var activeDiv = node.parentNode;
    node.parentNode.removeChild(node);
    return activeDiv;
}

I did an example on fiddle: https://jsfiddle.net/shhe05cj/4/

I run it on every keypress event that's bind to the relevant divs.

I based it on another thread that did something similar:Set caret position right after the inserted element in a contentEditable div

回答2:

Seems to work fine for me in this fiddle: http://jsfiddle.net/dgrundel/huL4sjem/

I'm using this code to check:

<div contenteditable="true" class="edit">
    This is editable.
</div>

<script>
    $('.edit').on('click', function(){
        console.log(document.activeElement);
    });
</script>

When I click into the editable element, console gets a copy of the div logged to it.

回答3:

$('#edit').on('click', function() {
  // this is the innermost *node*
  var an = window.getSelection().anchorNode;
  // this is the innermost *element*
  var ae = an;
  while (!( ae instanceof Element ))
    ae = ae.parentElement;
  $('#an').text(an.nodeValue);
  $('#ae').text(ae.outerHTML);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div contenteditable="true" id="edit">
  This is editable. <span>What?</span> <em>How about this?</em>
</div>
<br/>
Active Node:<br/>
<pre id="an">Nothing</pre>
<br/>
Active Element:<br/>
<pre id="ae">Nothing</pre>
<br/>

Here you go. Hit "Run snippet." Have fun.

The example below shows the behavior using the input event. This would mimic the behavior of a mutation observer.

$('#edit').on('input', function() {
  // this is the innermost *node*
  var an = window.getSelection().anchorNode;
  // this is the innermost *element*
  var ae = an;
  while (!( ae instanceof Element ))
    ae = ae.parentElement;
  $('#an').text(an.nodeValue);
  $('#ae').text(ae.outerHTML);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div contenteditable="true" id="edit">
  This is editable. <span>What?</span> <em>How about this?</em>
</div>
<br/>
Active Node:<br/>
<pre id="an">Nothing</pre>
<br/>
Active Element:<br/>
<pre id="ae">Nothing</pre>
<br/>

The example below shows the behavior using the keydown and keyup events. This would catch non-modifying keypresses like arrows and modifier keys.

$('#edit').on('keydown keyup', function() {
  // this is the innermost *node*
  var an = window.getSelection().anchorNode;
  // this is the innermost *element*
  var ae = an;
  while (!( ae instanceof Element ))
    ae = ae.parentElement;
  $('#an').text(an.nodeValue);
  $('#ae').text(ae.outerHTML);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div contenteditable="true" id="edit">
  This is editable. <span>What?</span> <em>How about this?</em>
</div>
<br/>
Active Node:<br/>
<pre id="an">Nothing</pre>
<br/>
Active Element:<br/>
<pre id="ae">Nothing</pre>
<br/>

回答4:

This does the job for me:

   $(document).click(function(event) {
            console.log(event.target);
        });