Justification in contentEditable div which each letter have own element

Question

I have got contentEditable div which each letter have own element, like:

<div contenteditable="true">
    <p id="p1">
        <span id="s1">S</span>
        <span id="s2">o</span>
        <span id="s3">m</span>
        <span id="s4">e</span>
        <span id="s5">&nbsp;</span>
        <span id="s6">t</span>
        <span id="s7">e</span>
        <span id="s8">x</span>
        <span id="s9">t</span>
    </p>
</div>

And I am trying to justify some longer text using text-align: justify, but this don't work. That is strange, because text-align: center and text-align: right works.

After that I am trying to do that using a script which adds margin-right to each space, but when I am writing new text into paragraph it crashes.

How can I do that (and save id and other attributes in each element) using JavaScript and/or JQuery?

Answer 1

Here is an example of a JS + jQuery way to simulate the justification for characters wrapped in spans inside a contenteditable element. It's just a quick proof of concept, tested in Chrome only, and not thoroughly. Functionalities like delete / undo / copy / paste, etc. were not added to this example.

var selectors = {
  'wrapper': '#editable',
  'paragraphs': '#editable > p',
  'spans': '#editable > p > span'
}

function get_cursor_position(element) {
  var caretOffset = 0;
  var doc = element.ownerDocument || element.document;
  var win = doc.defaultView || doc.parentWindow;
  var sel;
  if (typeof win.getSelection != "undefined") {
    sel = win.getSelection();
    if (sel.rangeCount > 0) {
      var range = win.getSelection().getRangeAt(0);
      var preCaretRange = range.cloneRange();
      preCaretRange.selectNodeContents(element);
      preCaretRange.setEnd(range.endContainer, range.endOffset);
      caretOffset = preCaretRange.toString().length;
    }
  } else if ((sel = doc.selection) && sel.type != "Control") {
    var textRange = sel.createRange();
    var preCaretTextRange = doc.body.createTextRange();
    preCaretTextRange.moveToElementText(element);
    preCaretTextRange.setEndPoint("EndToEnd", textRange);
    caretOffset = preCaretTextRange.text.length;
  }
  return caretOffset;
}


function set_cursor_position(pos) {
  if (document.selection) {
    sel = document.selection.createRange();
    sel.moveStart('character', pos);
    sel.select();
  } else {
    sel = window.getSelection();
    sel.collapse($(selectors['spans'])[pos].firstChild, 0);
  }
}

function set_cursor_position_to_element(el) {
  if (document.selection) {
    sel = document.selection.createRange();
    sel.moveStart('character', pos);
    sel.select();
  } else {
    sel = window.getSelection();
    sel.collapse(el, 0);
  }
}


function justify(wrapper_selector, children_selector) {
  var line_width = 0,
    first_line_char = 0,
    wrapper = $(wrapper_selector),
    wrapper_width = wrapper.width(),
    children = $(children_selector),
    position_of_last_space_found,
    filled_line_width_at_last_space_found;

  // refresh
  children.removeAttr("padding-right").removeClass("spaced first-line-char last-line-space");

  for (var space_positions = [], l = children.length, child_i = 0; child_i < l; child_i++) {
    child_e = children.eq(child_i);
    line_width += $(child_e).width();
    first_line_char += 1;
    if (/\s/g.test($(child_e).text())) {
      space_positions.push(child_i);
      position_of_last_space_found = child_i;
      filled_line_width_at_last_space_found = line_width - child_e.width();
    }
    if (line_width >= wrapper_width) {
      remaining_space = wrapper_width - filled_line_width_at_last_space_found;
      line_chars_extra_margin = remaining_space / (space_positions.length - 1);
      for (margin_i = 0; margin_i < space_positions.length; margin_i++) {
        children.eq(space_positions[margin_i]).addClass("spaced").css("padding-right", Math.floor(line_chars_extra_margin * 10) / 10);
      }
      children.eq(position_of_last_space_found + 1).addClass("first-line-char");
      children.eq(position_of_last_space_found).addClass("last-line-space");
      line_width = 0;
      child_i = position_of_last_space_found;
      first_line_char = 0;
      space_positions = [];
    }
  }
}

function insert_char(html) {
  var sel, range;
  if (window.getSelection) {
    sel = window.getSelection();
    if (sel.getRangeAt && sel.rangeCount) {
      range = sel.getRangeAt(0);
      range.deleteContents();
      var el = document.createElement("div");
      el.innerHTML = html;
      var frag = document.createDocumentFragment(),
        node, lastNode;
      while ((node = el.firstChild)) {
        lastNode = frag.appendChild(node);
      }
      var firstNode = frag.firstChild;
      pos = $(range.commonAncestorContainer).parent('span').index() + range.startOffset;
      $(selectors['spans']).eq(pos).before(frag);
      set_cursor_position(pos + 1, $(selectors['paragraphs']));
    }
  }
}

function get_span_at(x, y) {
  var $elements = $(selectors['spans']).map(function() {
    var $this = $(this);
    var offset = $this.offset();
    var l = offset.left;
    var t = offset.top;
    var h = $this.outerHeight(true);
    var w = $this.outerWidth(true);

    var maxx = l + w;
    var maxy = t + h;

    return (y <= maxy && y >= t) && (x <= maxx && x >= l) ? $this : null;
  });

  return $elements;
}

function init_demo() {
  var next_pos;

  // Copy the text from div.reference inside div.editable 
  // (only for the purpose of this example)
  var characters = $('div.reference p').text().trim().replace(/ /g, '\u00a0');
  for (var x = 0; x < characters.length; x++) {
    var c = characters.charAt(x);
    // wrap each character in a span
    $(selectors['paragraphs']).append("<span>" + c + "</span");
  }

  // initial justification
  justify(selectors['wrapper'], selectors['spans']);

  // re-justify on window resize
  $(window).resize(function() {
    clearTimeout(window.resizedFinished);
    window.resizedFinished = setTimeout(function() {
      justify(selectors['wrapper'], selectors['spans']);
    }, 20);
  });

  // Improve navigation with arrow keys
  $(selectors['wrapper']).on('keydown', function(e) {
    switch (e.which) {
      case 37: // left
        next_pos = get_cursor_position($(selectors['spans'])[0]) - 1;
        set_cursor_position(next_pos, $(selectors['paragraphs']));
        break;

      case 38: // up
        curr_pos = get_cursor_position($(selectors['spans'])[0]);
        curr_span = $(selectors['spans']).eq(curr_pos);
        curr_span_y = curr_span.position().top;
        curr_span_x = curr_span.position().left;
        next_span_y = curr_span_y - 1;
        next_span_x = curr_span_x + 1;
        next_span = get_span_at(curr_span_x, next_span_y);
        if (next_span[0]) {
          set_cursor_position_to_element(next_span[0][0]);
        }
        break;

      case 39: // right
        next_pos = get_cursor_position($(selectors['spans'])[0]);
        set_cursor_position(next_pos, $(selectors['paragraphs']));
        break;

      case 40: // down
        curr_pos = get_cursor_position($(selectors['spans'])[0]);
        curr_span = $(selectors['spans']).eq(curr_pos);
        curr_span_y = curr_span.position().top;
        curr_span_x = curr_span.position().left;
        curr_span_h = curr_span.outerHeight(true);
        next_span_y = curr_span_y + curr_span_h + 1;
        next_span_x = curr_span_x + 1;
        next_span = get_span_at(curr_span_x, next_span_y);
        if (next_span[0]) {
          set_cursor_position_to_element(next_span[0][0]);
        }
        break;
    }
  });

  // re-justify on character insertion
  $(selectors['wrapper']).on('keypress', function(e) {
    new_char = String.fromCharCode(e.which).replace(/ /g, '\u00a0');
    // Wrap new characters in spans
    new_el = '<span>' + new_char + '</span>';
    insert_char(new_el);
    justify(selectors['wrapper'], selectors['spans']);
    e.preventDefault();
  });

}

init_demo();

div.col {
  width: 50%;
  overflow: hidden;
  font-size: 1.2em;
  float: left;
  box-sizing: border-box;
  padding: 20px;
}

p {
  overflow: hidden;
}

div.reference p {
  text-align: justify;
}

div span {
  display: block;
  float: left;
}

.first-line-char {
  content: ' ';
  display: block;
  clear: left;
}

.last-line-space {
  display: none;
}

<script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
<div class="col col1">
  <h2>reference</h2>
  <h4>This is just a reference. Edit the right column.</h4>
  <div class="reference">
    <p>
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Excepturi provident, nemo incidunt voluptate officia, ipsa nulla itaque laudantium aperiam cupiditate vero, nesciunt consequuntur, facilis aliquam enim quis ad. Fugiat, magni.
    </p>
  </div>
</div>
<div class="col col2">
  <h2>editable</h2>
  <h4>Click the paragraph text below to start to edit.</h4>
  <div contenteditable="true" class="editable" id="editable">
    <p>
      <!-- Text will be copied from the reference div -->
    </p>
  </div>
</div>

Demo.