4

I'm trying to make a text editor that formats text based on what it says. For example, when you type "select", it changes the color of the word "select" to red. I'm using a contenteditable div.

I was able to make it change the color, but every time I change the text the caret (cursor) moves to the start of the div.

Here is my example:

var replace = function(text, q, r){
  text=text.split(q);
  var result = text[0];
  for(var i = 1; i < text.length; i++){
    result += r + text[i];
  }
  return result;
};

var run = function(){
  document.getElementById('code_editor').innerHTML
  = replace(document.getElementById('code_editor').textContent, "select", "<span class='start'>select</span>"); 
}
$('#code_editor').keyup(function (event) {
  run();
});
#code_editor {
  width: 600px;
  height: 100px;
  box-shadow: inset 0px 0px 2px black;
  padding: 5px;
  overflow-y: scroll;
}
.start {
  color: red;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<code><div id="code_editor" contenteditable tabindex="1"></div></code>

http://jsfiddle.net/wgw8ssL6/

Max Pelic
  • 41
  • 6

1 Answers1

0

I am not sure if you need the answer anymore but i will answer it anyways. So the approach is to update the caret position after updating the text of the div. 

var replace = function(text, q, r){
  text=text.split(q);
  var result = text[0];
  for(var i = 1; i < text.length; i++){
    result += r + text[i];
  }
  return result;
};

var run = function(){
  document.getElementById('code_editor').innerHTML
  = replace(document.getElementById('code_editor').textContent, "select", "<span class='start'>select</span>"); 
placeCaretAtEnd(document.getElementById('code_editor')); //Function invoke
}
/*Function to place caret at end*/
function placeCaretAtEnd(el) {
    el.focus();
    if (typeof window.getSelection != "undefined"
            && typeof document.createRange != "undefined") {
        var range = document.createRange();
        range.selectNodeContents(el);
        range.collapse(false);
        var sel = window.getSelection();
        sel.removeAllRanges();
        sel.addRange(range);
    } else if (typeof document.body.createTextRange != "undefined") {
        var textRange = document.body.createTextRange();
        textRange.moveToElementText(el);
        textRange.collapse(false);
        textRange.select();
    }
    console.log("[placeCaretAtEnd updated]");
}
$('#code_editor').keyup(function (event) {
  run();
});
#code_editor {
  width: 600px;
  height: 100px;
  box-shadow: inset 0px 0px 2px black;
  padding: 5px;
  overflow-y: scroll;
}
.start {
  color: red;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<code><div id="code_editor" contenteditable tabindex="1"></div></code>

Credits for the function

Aman
  • 439
  • 5
  • 15