Move caret position after focus() for ContentEditable <DIV> - javascript

I am trying to create a very basic rich-text editor in JavaScript but I'm having an issue with selections. So basically, since it's a contentEditable <div>, any time the user pastes in pre-formatted text from a webpage, the formatting doesn't get stripped off.
An easy to break hack is to give focus to a <textarea> upon Ctrl + V being pressed, so the text gets pasted in there, then onkeyup, give focus back to the <div>, copy the contents over and delete whatever went in to the <textarea>.
So that's easy, but when I give focus back to the contentEditable &;t;div>, the caret position is at the beginning and not immediately after the paste. I don't know enough about selections and whatnot to figure it out, so I'd appreciate some help. Here's my code:
// Helpers to keep track of the length of the thing we paste, the cursor position
// and a temporary random number so we can mark the position.
editor_stuff =
{
cursor_position: 0,
paste_length: 0,
temp_rand: 0,
}
// On key up (for the textarea).
document.getElementById("backup_editor").onkeyup = function()
{
var main_editor = document.getElementById("question_editor");
var backup_editor = document.getElementById("backup_editor");
var marker_position = main_editor.innerHTML.search(editor_stuff.temp_rand);
// Replace the "marker" with the .value of the <textarea>
main_editor.innerHTML = main_editor.innerHTML.replace(editor_stuff.temp_rand, backup_editor.value);
backup_editor.value = "";
main_editor.focus();
}
// On key down (for the contentEditable DIV).
document.getElementById("question_editor").onkeydown = function(event)
{
key = event;
// Grab control + V end handle paste so "plain text" is pasted and
// not formatted text. This is easy to break with Edit -> Paste or
// Right click -> Paste.
if
(
(key.keyCode == 86 || key.charCode == 86) && // "V".
(key.keyCode == 17 || key.charCode == 17 || key.ctrlKey) // "Ctrl"
)
{
// Create a random number marker at the place where we paste.
editor_stuff.temp_rand = Math.floor((Math.random() * 99999999));
document.getElementById("question_editor").textContent += editor_stuff.temp_rand;
document.getElementById("backup_editor").focus();
}
}
So my thinking is to store the cursor position (integer) in my helper array (editor_stuff.cursor_position).
N.B. I've been looking at other answers on SO all day and can't get any of them to work for me.

Here's a function that inserts text at the caret position:
Demo: http://jsfiddle.net/timdown/Yuft3/2/
Code:
function pasteTextAtCaret(text) {
var sel, range;
if (window.getSelection) {
// IE9 and non-IE
sel = window.getSelection();
if (sel.getRangeAt && sel.rangeCount) {
range = sel.getRangeAt(0);
range.deleteContents();
var textNode = document.createTextNode(text);
range.insertNode(textNode);
// Preserve the selection
range = range.cloneRange();
range.setStartAfter(textNode);
range.collapse(true);
sel.removeAllRanges();
sel.addRange(range);
}
} else if (document.selection && document.selection.type != "Control") {
// IE < 9
document.selection.createRange().text = text;
}
}

Related

Prevent loss of highlight when clicking on other element

I'm working on a blog where I want a section to add a post. I'm imagining it very similar to the StackExchange editor I'm using right now to write this post.
I've managed to work with the textarea to get things like current caret position, insert at position, etc.
The problem I'm running into now is not losing the highlighted text in the textarea when the user clicks on another element, ie: the bold tool.
By default (at least in Chrome) when you highlight text in a textarea and then click elsewhere on the page, the textarea loses focus and the highlighted text with it.
When the textarea loses focus it will by default lose any previous selection, so at the onblur event you can save the current selection using the following function:
function getSelectedText() {
var txtarea = document.getElementById(textBoxScript);
var start = txtarea.selectionStart;
var finish = txtarea.selectionEnd;
var sel = txtarea.value.substring(start, finish);
return sel;
}
And to set it back on focus event you can use the following function:
function selectText(startPos, endPos, tarea) {
// Chrome / Firefox
if (typeof (tarea.selectionStart) != "undefined") {
tarea.focus();
tarea.selectionStart = startPos;
tarea.selectionEnd = endPos;
return true;
}
// IE
if (document.selection && document.selection.createRange) {
tarea.focus();
tarea.select();
var range = document.selection.createRange();
range.collapse(true);
range.moveEnd("character", endPos);
range.moveStart("character", startPos);
range.select();
return true;
}
}

Determine when caret reaches the end of input box

I have found this question which provides a solution to compute the exact position of the caret in a text or input box.
For my purposes, this is overkill. I only want to know when the caret is at the end of all the text of an input box. Is there an easy way to do that?
In all modern browsers:
//input refers to the text box
if(input.value.length == input.selectionEnd){
//Caret at end.
}
The selectionEnd property of an input element equals the highest selection index.
<script>
input = document.getElementById('yourinputfieldsid');
if(input.selectionEnd == input.selectionStart && input.value.length == input.selectionEnd){
//your stuff
}
</script>
This checks to see if the caret actually is at the end, and makes sure that it isn't only because of the selection that it shows an end value.
You don't specify what you want to happen when some text is selected, so in that case my code just checks whether the end of the selection is at the end of the input.
Here's a cross-browser function that wil work in IE < 9 (which other answers will not: IE only got selectionStart and selectionEnd in version 9).
Live demo: http://jsfiddle.net/vkCpH/1/
Code:
function isCaretAtTheEnd(el) {
var valueLength = el.value.length;
if (typeof el.selectionEnd == "number") {
// Modern browsers
return el.selectionEnd == valueLength;
} else if (document.selection) {
// IE < 9
var selRange = document.selection.createRange();
if (selRange && selRange.parentElement() == el) {
// Create a working TextRange that lives only in the input
var range = el.createTextRange();
range.moveToBookmark(selRange.getBookmark());
return range.moveEnd("character", valueLength) == 0;
}
}
return false;
}

How to find if a HTMLElement is enclosed in Selected text

Is it possible to find out if an HTMLElement is totally enclosed within the selection?
I have a scenario where user selects some text in a HTML editor and applies some custom style from a list. Now I need to change the class attribute of each span element that is enclosed in that selection and surrounding the selection with a new span with the selected style.
Am able to find out if a particular span element is in selection by using DOM Range's compareBoundaryPoints method in firefox and safari but it will not work for IE.
Is there any way to find out if an element is totally enclosed with in the selected range for IE?
Thanks
Kapil
As #standardModel says, Rangy gives you full* DOM Range support in IE and has a helpful getNodes() method that you could use:
var sel = rangy.getSelection();
if (sel.rangeCount) {
var range = sel.getRangeAt(0);
var spans = range.getNodes([1], function(node) {
return node.nodeName.toLowerCase() == "span" && range.containsNode(node);
});
// Do stuff with spans here
}
If you'd rather not use something as bulky as Rangy, the following function will tell you if an element is completely selected:
function isSelected(el) {
if (window.getSelection) {
var sel = window.getSelection();
var elRange = document.createRange();
elRange.selectNodeContents(el);
for (var i = 0, range; i < sel.rangeCount; ++i) {
range = sel.getRangeAt(i);
if (range.compareBoundaryPoints(range.START_TO_START, elRange) <= 0
&& range.compareBoundaryPoints(range.END_TO_END, elRange) >= 0) {
return true;
}
}
} else if (document.selection && document.selection.type == "Text") {
var textRange = document.selection.createRange();
var elTextRange = textRange.duplicate();
elTextRange.moveToElementText(el);
return textRange.inRange(elTextRange);
}
return false;
}
jsFiddle example: http://jsfiddle.net/54eGr/1/
(*) Apart from handling Range updates under DOM mutation
You may want to take a look at Rangy. This makes xbrowser Ranges and Selections a lot easier.

Problem with two JavaScript codes

I have these two codes -
new function($) {
$.fn.getCursorPosition = function() {
var pos = 0;
var el = $(this).get(0);
// IE Support
if (document.selection) {
el.focus();
var Sel = document.selection.createRange();
var SelLength = document.selection.createRange().text.length;
Sel.moveStart('character', -el.value.length);
pos = Sel.text.length - SelLength;
}
// Firefox support
else if (el.selectionStart || el.selectionStart == '0')
pos = el.selectionStart;
return pos;
}
} (jQuery);
And
var element = document.getElementById('txtarr');
if( document.selection ){
// The current selection
var range = document.selection.createRange();
// We'll use this as a 'dummy'
var stored_range = range.duplicate();
// Select all text
stored_range.moveToElementText( element );
// Now move 'dummy' end point to end point of original range
stored_range.setEndPoint( 'EndToEnd', range );
// Now we can calculate start and end points
element.selectionStart = stored_range.text.length - range.text.length;
element.selectionEnd = element.selectionStart + range.text.length;
}
The first one is for getting the cursor position in a textarea and the second one is for determining the end of a textarea ,but they give the same result?
Where's the mistake?
I fix it.It's very simple :) .
I just replace the second code(for determining the end of the textarea) with:$("#txtarr").val().length(jQuery).#txtarr is the id of mine textarea.
Both pieces of code are doing the same thing in slightly different ways. Each is attempting to get the position of the caret or selection in a textarea (or text input), although the first only gets the start position of the selection while the second gets both the start and end positions.
Both have flaky inferences: the first assumes a browser featuring document.selection will support TextRange, while the second makes the same inference plus another that assumes a browser without support for document.selection will have support for selectionStart and selectionEnd properties of textareas. Neither will correctly handle line breaks in IE. For code that does that, see my answer here: How to get the start and end points of selection in text area?

Contenteditable text editor and cursor position

How can I (using jquery or other) insert html at the cursor/caret position of my contenteditable div:
<div contenteditable="true">Hello world</div>
For example, if the cursor/caret was between "hello" and "world" and the user then clicked a button, eg "insert image", then using javascript, something like <img src=etc etc> would be inserted between "hello" and "world". I hope I've made this clear =S
Example code would be greatly appreciated, thanks a lot!
The following function will insert a DOM node (element or text node) at the cursor position in all the mainstream desktop browsers:
function insertNodeAtCursor(node) {
var sel, range, html;
if (window.getSelection) {
sel = window.getSelection();
if (sel.getRangeAt && sel.rangeCount) {
sel.getRangeAt(0).insertNode(node);
}
} else if (document.selection && document.selection.createRange) {
range = document.selection.createRange();
html = (node.nodeType == 3) ? node.data : node.outerHTML;
range.pasteHTML(html);
}
}
If you would rather insert an HTML string:
function insertHtmlAtCursor(html) {
var sel, range, node;
if (window.getSelection) {
sel = window.getSelection();
if (sel.getRangeAt && sel.rangeCount) {
range = window.getSelection().getRangeAt(0);
node = range.createContextualFragment(html);
range.insertNode(node);
}
} else if (document.selection && document.selection.createRange) {
document.selection.createRange().pasteHTML(html);
}
}
I've adapted this from my answer to a similar question: How to find cursor position in a contenteditable DIV?
With contenteditable you should use execCommand.
Try document.execCommand('insertImage', false, 'image.jpg') or document.execCommand('insertHTML', false, '<img src="image.jpg" alt="" />'). The second doesn't work in older IE.
in this code i have just replace html code with (") to (')
use this syntax:
$("div.second").html("your html code and replace with (")to(') ");
I would recommend the use of the jquery plugin a-tools
This plugin has seven functions:
* getSelection – return start, end position, length of the selected text and the selected text. return start=end=caret position if text is not selected;
* replaceSelection – replace selected text with a given string;
* setSelection – select text in a given range (startPosition and endPosition);
* countCharacters – count amount of all characters;
* insertAtCaretPos – insert text at current caret position;
* setCaretPos – set cursor at caret position (1 = beginning, -1 = end);
* setMaxLength – set maximum length of input field. Also provides callback function if limit is reached. Note: The function has to have a number as input. Positive value for setting of limit and negative number for removing of limit.
The one that you need is insertAtCaretPos:
$("#textarea").insertAtCaretPos("<img src=etc etc>");
There might be a draw-back: this plugins only works with textarea en input:text elements, so there may be conflicts with contenteditable.

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