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Input not scrolling to the far right like it should

I have an input field where i append data at the cursor position.
after that, i set the selectionStart to the end of the field.
BUT, whenever i add something to the input (by button clicks), i only see the left part of it (until it reaches the right edge). everything more is there (i can select it with the mouse and scroll), but it doesn't automatically show the right edge.
how can i do that?
i want to add something to the input and jump right to the end of the string.
// add 2 digit number
$('button#2digit').on('click', function add2digit() {
addNumberToInput(10, 99);
});
function addNumberToInput(min, max) {
var problemInput = $('input#testProblem');
if (lastCharIsOperation() || problemInput.val().trim() < 1) { // if last char is an operation or first in string, just append the number
addAtCursor(randomNonPrime(min, max));
} else {
addAtCursor('+' + randomNonPrime(min, max));
}
}
function addAtCursor(toAdd) {
var problemInput = $('input#testProblem');
var oldText = problemInput.val();
var cursor = problemInput[0].selectionStart;
var pre = oldText.substring(0,cursor);
var post = oldText.substring(cursor, oldText.length);
//insert at cursor
problemInput.val(pre + toAdd + post);
//put cursor to end
problemInput[0].selectionStart = problemInput.val().length;
}
(it even skips back to the left on blur, i couldn't make a picture with the windows snipping tool, because i had to click it first)

From Set mouse focus and move cursor to end of input using jQuery.
var problemInput = $('input#testProblem');
problemInput.focus();
var t=problemInput.val();
problemInput.val('');
problemInput.val(t);
Here is the start of a full solution: https://jsfiddle.net/michaelgentry/vwm159pt/

This will still cause the scroll to jump back to the left on blur, but does what you are asking:
var elem = document.getElementById('myInput');
elem.focus();
elem.scrollLeft = elem.scrollWidth;

How can I best make an inline span draggable within a paragraph of text?

I have a paragraph of text in which the user may place a "pin" to mark a position. Once a pin has been placed, I would like to allow the user to move its position by dragging it to a new location in the paragraph. This is simple to do with block elements, but I have yet to see a good way to do it with inline elements. How might I accomplish this?
I have already implemented it using window.selection as a way to find the cursor's location in the paragraph, but it is not as smooth as I would like.
As a note, I am using the Rangy library to wrap the native Range and Selection functionality, but it works the same way as the native functions do.
Here is the code:
$(document).on("mousedown", '.pin', function () {
//define what a pin is
var el = document.createElement("span");
el.className = "pin";
el.id = "test";
//make it contain an empty space so we can color it
el.appendChild(document.createTextNode("d"));
$(document).on("mousemove", function () {
//get the current selection
var selection = rangy.getSelection();
//collapse the selection to either the front
//or back, since we do not want the user to see it.
if (selection.isBackwards()) {
selection.collapseToStart();
} else {
selection.collapseToEnd();
}
//remove the old pin
$('.pin').remove();
//place the new pin at the current selection
selection.getAllRanges()[0].insertNode(el);
});
//remove the handler when the user has stopped dragging it
$(document).on("mouseup", function () {
$(document).off("mousemove");
});
});
And here is a working demo: http://jsfiddle.net/j1LLmr5b/22/ .
As you can see, it works(usually), but the user can see the selection being made. Have any ideas on how to move the span without showing the selection highlight? I will also accept an alternate method that does not use the selection at all. The goal is to allow movement of the span as cleanly as possible.

You can do this using ranges instead using code similar to this answer. Unfortunately the code is a bit longer than ideal because IE hasn't yet implemented document.caretPositionFromPoint(). However, the old proprietary TextRange object, still present in IE 11, comes to the rescue.
Here's a demo:
http://jsfiddle.net/j1LLmr5b/26/
Here's the relevant code:
var range, textRange, x = e.clientX, y = e.clientY;
//remove the old pin
$('.pin').remove();
// Try the standards-based way first
if (document.caretPositionFromPoint) {
var pos = document.caretPositionFromPoint(x, y);
range = document.createRange();
range.setStart(pos.offsetNode, pos.offset);
range.collapse();
}
// Next, the WebKit way
else if (document.caretRangeFromPoint) {
range = document.caretRangeFromPoint(x, y);
}
// Finally, the IE way
else if (document.body.createTextRange) {
textRange = document.body.createTextRange();
textRange.moveToPoint(x, y);
var spanId = "temp_" + ("" + Math.random()).slice(2);
textRange.pasteHTML('<span id="' + spanId + '"> </span>');
var span = document.getElementById(spanId);
//place the new pin
span.parentNode.replaceChild(el, span);
}
if (range) {
//place the new pin
range.insertNode(el);
}

Try this my friend
el.appendChild(document.createTextNode("d"));
You have create empty span tag that's why you found empty.

add after
el.id = "test";
this
var value = $('.pin').text();
$(el).text(value);
You can hide selection with css
::selection {color:red;background:yellow;}
::-moz-selection {color:red;background:yellow;}
that's all how i can help for a now

Move the cursor position with Javascript?

I'm looking to move the caret exactly four spaces ahead of its current position so that I can insert a tab properly. I've already got the HTML insertion at the caret's position working, but when I insert the HTML, the caret is left behind. I've spent the past hour or so looking at various ways to do this and I've tried plenty of them, but I can't get any of them to work for me. Here's the most recent method I've tried:
function moveCaret(input, distance) {
if(input.setSelectionRange) {
input.focus();
input.setSelectionRange(distance, distance);
} else if(input.createTextRange) {
var range = input.createTextRange();
range.collapse(true);
range.moveEnd(distance);
range.moveStart(distance);
range.select();
}
}
It does absolutely nothing--doesn't move the caret, throw any errors or anything. This leaves me baffled. And yes, I know that the above method set (is supposed to) set the caret at a certain position from the beginning of the specified node (that is, input), but even that's not working. So, what exactly am I doing wrong, and how can I do it right?
Edit: Based on the links that o.v. provided, I've managed to cobble something together that's finally doing something: throwing an error. Yay! Here's the new code:
this.moveCaret = function(distance) {
if(that.win.getSelection) {
var range = that.win.getSelection().getRangeAt(0);
range.setStart(range.startOffset + distance);
} else if (that.win.document.selection) {
var range = that.win.document.selection.createRange();
range.setStart(range.startOffset + distance);
}
}
Now, this gives the error Uncaught Error: NOT_FOUND_ERR: DOM Exception 8. Any ideas why?

The code snippet you have is for text inputs and textareas, not contenteditable elements.
Provided that all your content is in a single text node and the selection is completely contained within it, the following will work in all major browsers, including IE 6.
Demo: http://jsfiddle.net/9sdrZ/
Code:
function moveCaret(win, charCount) {
var sel, range;
if (win.getSelection) {
// IE9+ and other browsers
sel = win.getSelection();
if (sel.rangeCount > 0) {
var textNode = sel.focusNode;
var newOffset = sel.focusOffset + charCount;
sel.collapse(textNode, Math.min(textNode.length, newOffset));
}
} else if ( (sel = win.document.selection) ) {
// IE <= 8
if (sel.type != "Control") {
range = sel.createRange();
range.move("character", charCount);
range.select();
}
}
}

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?

JavaScript 'contenteditable' -- Getting/Setting Caret Position

I have read a few posts on positioning the caret, but none seem to answer my particular issue.
I have 2 divs (div1 and div2)
div1 = noneditable div
div2 = contenteditable div
both divs contain exact same contents
when user clicks on div1, it gets hidden, and div2 appears in exact location and user can edit
The problem: I want the caret to appear in exact location on div2 as div1
So, I need some way to READ the location where the user clicks on div1, and then when div2 appears place the cursor/caret in that same location, so a getCaretLocation(in_div_id) and setCaretLocation(in_div_id) set of functions.
Any way to do that?
Thanks -

Short answer : You can't
Long answer : The problem you'll face is that you'll be able to get (x,y) coordinates for the click event on div1, but any implementation of the caret position while require you knowing the position of the caret in the content (which is the number of characters preceding the caret).
To convert the (x,y) coordinates to a character position you actually need to know how many characters were before (ie. left on the current line and above, if the text is ltr).
If you use a fixed width font, you can simplify the problem : mapping an (x,y) coordinate to a (line, column) coordinate on a character grid.
However, you still face the problem of not knowing how the text is wrapped. For example :
------------------
|Lorem ipsum |
|dolor sit amet |
|consectetur |
|adipiscing elit |
------------------
If the user clicks on the d in dolor, you know that the character is the 1st on the 2nd line, but without knowing the wrapping algorithm there is no way you'll know that it is the 13th character in "Lorem ipsum dolor sit…". And there is no guarantee that such a wrapping algorithm is identical across browsers and platform.
Now, what I'm wondering is why would you use 2 different synced div in the first place ? Wouldn't it be easier to use only one div and set its content to editable when the user clicks (or hovers) ?

You could insert a tiny span-element at the caret, get its position, and remove it. For a cross-browser range and selection library, see rangy.

you can, basically you need set temporary content editable on your first div to catch caret pos
$('div1').hover(function()
{ $(this).attr('contenteditable','true');
},function()
{ $(this).removeAttr('contenteditable');
}).mouseup(function()
{ var t = $(this);
// get caret position and remove content editable
var caret = t.getCaret();
t.removeAttr('contenteditable');
// do your div switch stuff
...
// and apply saved caret position
$('div2').setCaret(caret);
});
now just need get/set caret method :)
edit > here is my own, (live demo)
getSelection:function($e)
{ if(undefined === window.getSelection) return false;
var range = window.getSelection().getRangeAt(0);
function getTreeOffset($root,$node)
{ if($node.parents($root).length === 0) return false; // is node child of root ?
var tree = [], treesize = 0;
while(1)
{ if($node.is($root)) break;
var index, $parent = $node.parent();
index = $parent.contents().index($node);
if(index !== -1) { tree[treesize++] = index; } $node = $parent;
}; return tree.reverse();
}
var start = getTreeOffset($e,$(range.startContainer));
var end = getTreeOffset($e,$(range.endContainer));
if(start & end === false) return false;
return {start:start,end:end,startOffset:range.startOffset,endOffset:range.endOffset};
}, setSelection:function($e,s,win)
{ $e.focus(); if(s === false) return; var sel = win.getSelection(); sel.removeAllRanges();
function getNode($e,s)
{ var node = $e;
for( var n=0;n<s.length;n++ )
{ var index = s[n]; if(index < 0) break;
node = node.contents(':eq('+index+')');
} return node.get(0);
}
var start = getNode($e,s.start), end = getNode($e,s.end), range = win.document.createRange();
range.setStart(start,s.startOffset); range.setEnd(end,s.endOffset); sel.addRange(range);
}

It sounds like you are trying to do an inline edit... have you looked at the jeditable plugin?

When you click on an element, a Selection object with zero length is created (get it from element.getSelection() , where element is the div in question). The focusOffset of that object will let you know that you clicked on, for example, the 74th character in that div (this is the thing that Adrien said was impossible in a different answer).