The Setup
So, I have a contenteditable div -- I'm making a WYSIWYG editor: bold, italics, formatting, whatever, and most lately: inserting fancy images (in a fancy box, with a caption).
<a class="fancy" href="i.jpg" target="_blank">
<img alt="" src="i.jpg" />
Optional Caption goes Here!
</a>
The user adds these fancy images with a dialog I present them with: they fill out the details, upload the image, and then much like the other editor functions, I use document.execCommand('insertHTML',false,fancy_image_html); to plop it in at the user's selection.
Desired Functionality
So, now that my user can plop in a fancy image -- they need to be able to move it around.
The user needs to be able to click and drag the image (fancy box and all) to place it anywhere that they please within the contenteditable. They need to be able to move it between paragraphs, or even within paragraphs -- between two words if they want.
What gives me hope
Keep in mind -- in a contenteditable, plain old <img> tags are already blessed by the user-agent with this lovely drag-and-drop capability. By default, you can drag and drop <img> tags around wherever you please; the default drag-and-drop operation behaves as one would dream.
So, considering how this default behavior already works so smashingly on our <img> buddies -- and I only want to extend this behaviour a little bit to include a tad more HTML -- this seems like something that should be easily possible.
My Efforts Thus Far
First, I set up my fancy <a> tag with the draggable attribute, and disabled contenteditable (not sure if that's necessary, but it seems like it may as well be off):
<a class="fancy" [...] draggable="true" contenteditable="false">
Then, because the user could still drag the image out of the fancy <a> box, I had to do some CSS. I'm working in Chrome, so I'm only showing you the -webkit- prefixes, though I used the others too.
.fancy {
-webkit-user-select:none;
-webkit-user-drag:element; }
.fancy>img {
-webkit-user-drag:none; }
Now the user can drag the whole fancy box, and the little partially-faded click-drag representation image reflects this -- I can see that I'm picking up the entire box now :)
I've tried several combinations of different CSS properties, the above combo seems to make sense to me, and seems to work best.
I was hoping that this CSS alone would be enough for the browser to use the entire element as the draggable item, automagically granting the user the functionality I've been dreaming of... It does however, appear to be more complicated than that.
HTML5's JavaScript Drag and Drop API
This Drag and Drop stuff seems more complicated than it needs to be.
So, I started getting deep into DnD api docs, and now I'm stuck. So, here's what I've rigged up (yes, jQuery):
$('.fancy')
.bind('dragstart',function(event){
//console.log('dragstart');
var dt=event.originalEvent.dataTransfer;
dt.effectAllowed = 'all';
dt.setData('text/html',event.target.outerHTML);
});
$('.myContentEditable')
.bind('dragenter',function(event){
//console.log('dragenter');
event.preventDefault();
})
.bind('dragleave',function(event){
//console.log('dragleave');
})
.bind('dragover',function(event){
//console.log('dragover');
event.preventDefault();
})
.bind('drop',function(event){
//console.log('drop');
var dt = event.originalEvent.dataTransfer;
var content = dt.getData('text/html');
document.execCommand('insertHTML',false,content);
event.preventDefault();
})
.bind('dragend',function(event){
//console.log('dragend');
});
So here's where I'm stuck: This almost completely works. Almost completely. I have everything working, up until the very end. In the drop event, I now have access to the fancy box's HTML content that I'm trying to have inserted at the drop location. All I need to do now, is insert it at the correct location!
The problem is I can't find the correct drop location, or any way to insert to it. I've been hoping to find some kind of 'dropLocation' object to dump my fancy box into, something like dropEvent.dropLocation.content=myFancyBoxHTML;, or perhaps, at least, some kind of drop location values with which to find my own way to put the content there?
Am I given anything?
Am I doing it completely wrong? Am I completely missing something?
I tried to use document.execCommand('insertHTML',false,content); like I expected I should be able to, but it unfortunately fails me here, as the selection caret is not located at the precise drop location as I'd hope.
I discovered that if I comment out all of the event.preventDefault();'s, the selection caret becomes visible, and as one would hope, when the user prepares to drop, hovering their drag over the contenteditable, the little selection caret can be seen running along between characters following the user's cursor and drop operation -- indicating to the user that the selection caret represents the precise drop location. I need the location of this selection caret.
With some experiments, I tried execCommand-insertHTML'ing during the drop event, and the dragend event -- neither insert the HTML where the dropping-selection-caret was, instead it uses whatever location was selected prior to the drag operation.
Because the selection caret is visible during dragover, I hatched a plan.
For awhile, I was trying, in the dragover event, to insert a temporary marker, like <span class="selection-marker">|</span>, just after $('.selection-marker').remove();, in an attempt for the browser to constantly (during dragover) be deleting all selection markers and then adding one at the insertion point -- essentially leaving one marker wherever that insertion point is, at any moment. The plan of course, was to then replace this temporary marker with the dragged content which I have.
None of this worked, of course: I couldn't get the selection-marker to insert at the apparently visible selection caret as planned -- again, the execCommand-insertedHTML placed itself wherever the selection caret was, prior to the drag operation.
Huff. So what have I missed? How is it done?
How do I obtain, or insert into, the precise location of a drag-and-drop operation?
I feel like this is, obviously, a common operation among drag-and-drops -- surely I must have overlooked an important and blatant detail of some kind? Did I even have to get deep into JavaScript, or maybe there's a way to do this just with attributes like draggable, droppable, contenteditable, and some fancydancy CSS3?
I'm still on the hunt -- still tinkering around -- I'll post back as soon as I find out what I've been failing at :)
The Hunt Continues (edits after original post)
Farrukh posted a good suggestion -- use:
console.log( window.getSelection().getRangeAt(0) );
To see where the selection caret actually is. I plopped this into the dragover event, which is when I figure the selection caret is visibily hopping around between my editable content in the contenteditable.
Alas, the Range object that is returned, reports offset indices that belong to the selection caret prior to the drag-and-drop operation.
It was a valiant effort. Thanks Farrukh.
So what's going on here? I am getting the sensation that the little selection caret I see hopping around, isn't the selection caret at all! I think it's an imposter!
Upon Further Inspection!
Turns out, it is an imposter! The real selection caret remains in place during the entire drag operation! You can see the little bugger!
I was reading MDN Drag and Drop Docs, and found this:
Naturally, you may need to move the insertion marker around a dragover event as well. You can use the event's clientX and clientY properties as with other mouse events to determine the location of the mouse pointer.
Yikes, does this mean I'm supposed to figure it out for myself, based on clientX and clientY?? Using mouse coordinates to determine the location of the selection caret myself? Scary!!
I'll look into doing so tomorrow -- unless myself, or somebody else here reading this, can find a sane solution :)
Dragon Drop
I've done a ridiculous amount of fiddling. So, so much jsFiddling.
This is not a robust, or complete solution; I may never quite come up with one. If anyone has any better solutions, I'm all ears -- I didn't want to have to do it this way, but it's the only way I've been able to uncover so far. The following jsFiddle, and the information I am about to vomit up, worked for me in this particular instance with my particular versions of Firefox and Chrome on my particular WAMP setup and computer. Don't come crying to me when it doesn't work on your website. This drag-and-drop crap is clearly every man for himself.
jsFiddle: Chase Moskal's Dragon Drop
So, I was boring my girlfriend's brains out, and she thought I kept saying "dragon drop" when really, I was just saying "drag-and-drop". It stuck, so that's what I call my little JavaScript buddy I've created for handling these drag-and-drop situations.
Turns out -- it's a bit of a nightmare. The HTML5 Drag-and-Drop API even at first glance, is horrible. Then, you almost warm up to it, as you start to understand and accept the way it's supposed to work.. Then you realize what a terrifying nightmare it actually is, as you learn how Firefox and Chrome go about this specification in their own special way, and seem to completely ignore all of your needs. You find yourself asking questions like: "Wait, what element is even being dragged right now? How to do I get that information? How do I cancel this drag operation? How can I stop this particular browser's unique default handling of this situation?"... The answers to your questions: "You're on your own, LOSER! Keep hacking things in, until something works!".
So, here's how I accomplished Precise Drag and Drop of Arbitrary HTML Elements within, around, and between multiple contenteditable's. (note: I'm not going fully in-depth with every detail, you'll have to look at the jsFiddle for that -- I'm just rambling off seemingly relevant details that I remember from the experience, as I have limited time)
My Solution
First, I applied CSS to the draggables (fancybox) -- we needed user-select:none; user-drag:element; on the fancy box, and then specifically user-drag:none; on the image within the fancy box (and any other elements, why not?). Unfortunately, this was not quite enough for Firefox, which required attribute draggable="false" to be explicitly set on the image to prevent it from being draggable.
Next, I applied attributes draggable="true" and dropzone="copy" onto the contenteditables.
To the draggables (fancyboxes), I bind a handler for dragstart. We set the dataTransfer to copy a blank string of HTML ' ' -- because we need to trick it into thinking we are going to drag HTML, but we are cancelling out any default behavior. Sometimes default behavior slips in somehow, and it results in a duplicate (as we do the insertion ourselves), so now the worst glitch is a ' ' (space) being inserted when a drag fails. We couldn't rely on the default behavior, as it would fail to often, so I found this to be the most versatile solution.
DD.$draggables.off('dragstart').on('dragstart',function(event){
var e=event.originalEvent;
$(e.target).removeAttr('dragged');
var dt=e.dataTransfer,
content=e.target.outerHTML;
var is_draggable = DD.$draggables.is(e.target);
if (is_draggable) {
dt.effectAllowed = 'copy';
dt.setData('text/plain',' ');
DD.dropLoad=content;
$(e.target).attr('dragged','dragged');
}
});
To the dropzones, I bind a handler for dragleave and drop. The dragleave handler exists only for Firefox, as in Firefox, the drag-drop would work (Chrome denies you by default) when you tried to drag it outside the contenteditable, so it performs a quick check against the Firefox-only relatedTarget. Huff.
Chrome and Firefox have different ways of acquiring the Range object, so effort had to be put in to do it differently for each browser in the drop event. Chrome builds a range based on mouse-coordinates (yup that's right), but Firefox provides it in the event data. document.execCommand('insertHTML',false,blah) turns out to be how we handle the drop. OH, I forgot to mention -- we can't use dataTransfer.getData() on Chrome to get our dragstart set HTML -- it appears to be some kind of weird bug in the specification. Firefox calls the spec out on it's bullcrap and gives us the data anyways -- but Chrome doesn't, so we bend over backwards and to set the content to a global, and go through hell to kill all the default behavior...
DD.$dropzones.off('dragleave').on('dragleave',function(event){
var e=event.originalEvent;
var dt=e.dataTransfer;
var relatedTarget_is_dropzone = DD.$dropzones.is(e.relatedTarget);
var relatedTarget_within_dropzone = DD.$dropzones.has(e.relatedTarget).length>0;
var acceptable = relatedTarget_is_dropzone||relatedTarget_within_dropzone;
if (!acceptable) {
dt.dropEffect='none';
dt.effectAllowed='null';
}
});
DD.$dropzones.off('drop').on('drop',function(event){
var e=event.originalEvent;
if (!DD.dropLoad) return false;
var range=null;
if (document.caretRangeFromPoint) { // Chrome
range=document.caretRangeFromPoint(e.clientX,e.clientY);
}
else if (e.rangeParent) { // Firefox
range=document.createRange(); range.setStart(e.rangeParent,e.rangeOffset);
}
var sel = window.getSelection();
sel.removeAllRanges(); sel.addRange(range);
$(sel.anchorNode).closest(DD.$dropzones.selector).get(0).focus(); // essential
document.execCommand('insertHTML',false,'<param name="dragonDropMarker" />'+DD.dropLoad);
sel.removeAllRanges();
// verification with dragonDropMarker
var $DDM=$('param[name="dragonDropMarker"]');
var insertSuccess = $DDM.length>0;
if (insertSuccess) {
$(DD.$draggables.selector).filter('[dragged]').remove();
$DDM.remove();
}
DD.dropLoad=null;
DD.bindDraggables();
e.preventDefault();
});
Okay, I'm sick of this. I've wrote all I want to about this. I'm calling it a day, and might update this if I think of anything important.
Thanks everybody. //Chase.
Since I wanted to see this in a native JS solution I worked a bit to remove all jQuery dependencies. Hopefully it can help someone.
First the markup
<div class="native_receiver" style="border: 2px solid red;padding: 5px;" contenteditable="true" >
WAITING FOR STUFF
</div>
<div class="drawer" style="border: 2px solid #AAE46A; padding: 10px">
<span class="native_drag" data-type="dateselector" contenteditable="false" draggable="true" style="border: 2px solid rgba(0,0,0,0.2);padding:4px; margin:2px">
Block 1
</span>
<span class="native_drag" data-type="dateselector" contenteditable="false" draggable="true" style="border: 2px solid rgba(0,0,0,0.2);padding:4px; margin:2px">
Second Blk
</span>
</div>
Then some helpers
function addClass( elem, className ){
var classNames = elem.className.split( " " )
if( classNames.indexOf( className ) === -1 ){
classNames.push( className )
}
elem.className = classNames.join( " " )
}
function selectElem( selector ){
return document.querySelector( selector )
}
function selectAllElems( selector ){
return document.querySelectorAll( selector )
}
function removeElem( elem ){
return elem ? elem.parentNode.removeChild( elem ) : false
}
Then the actual methods
function nativeBindDraggable( elems = false ){
elems = elems || selectAllElems( '.native_drag' );
if( !elems ){
// No element exists, abort
return false;
}else if( elems.outerHTML ){
// if only a single element, put in array
elems = [ elems ];
}
// else it is html-collection already (as good as array)
for( let i = 0 ; i < elems.length ; i++ ){
// For every elem in list, attach or re-attach event handling
elems[i].dataset.transferreference = `transit_${ new Date().getTime() }`;
elems[i].ondragstart = function(e){
if (!e.target.id){
e.target.id = (new Date()).getTime();
}
window.inTransferMarkup = e.target.outerHTML;
window.transferreference = elems[i].dataset.transferreference;
addClass( e.target, 'dragged');
};
};
}
function nativeBindWriteRegion( elems = false ){
elems = elems || selectAllElems( '.native_receiver' );
if( !elems ){
// No element exists, abort
return false;
}else if( elems.outerHTML ){
// if only a single element, put in array
elems = [ elems ];
}
// else it is html-collection
for( let i = 0 ; i < elems.length ; i++ ){
elems[i].ondragover = function(e){
e.preventDefault();
return false;
};
elems[i].ondrop = function(e){
receiveBlock(e);
};
}
}
function receiveBlock(e){
e.preventDefault();
let content = window.inTransferMarkup;
window.inTransferMarkup = "";
let range = null;
if (document.caretRangeFromPoint) { // Chrome
range = document.caretRangeFromPoint(e.clientX, e.clientY);
}else if (e.rangeParent) { // Firefox
range = document.createRange();
range.setStart(e.rangeParent, e.rangeOffset);
}
let sel = window.getSelection();
sel.removeAllRanges();
sel.addRange( range );
e.target.focus();
document.execCommand('insertHTML',false, content);
sel.removeAllRanges();
// reset draggable on all blocks, esp the recently created
nativeBindDraggable(
document.querySelector(
`[data-transferreference='${window.transferreference}']`
)
);
removeElem( selectElem( '.dragged' ) );
return false;
}
And lastly instantiate
nativeBindDraggable();
nativeBindWriteRegion();
Below is the functioning snippet
function addClass( elem, className ){
var classNames = elem.className.split( " " )
if( classNames.indexOf( className ) === -1 ){
classNames.push( className )
}
elem.className = classNames.join( " " )
}
function selectElem( selector ){
return document.querySelector( selector )
}
function selectAllElems( selector ){
return document.querySelectorAll( selector )
}
function removeElem( elem ){
return elem ? elem.parentNode.removeChild( elem ) : false
}
function nativeBindDraggable( elems = false ){
elems = elems || selectAllElems( '.native_drag' );
if( !elems ){
// No element exists, abort
return false;
}else if( elems.outerHTML ){
// if only a single element, put in array
elems = [ elems ];
}
// else it is html-collection already (as good as array)
for( let i = 0 ; i < elems.length ; i++ ){
// For every elem in list, attach or re-attach event handling
elems[i].dataset.transferreference = `transit_${ new Date().getTime() }`;
elems[i].ondragstart = function(e){
if (!e.target.id){
e.target.id = (new Date()).getTime();
}
window.inTransferMarkup = e.target.outerHTML;
window.transferreference = elems[i].dataset.transferreference;
addClass( e.target, 'dragged');
};
};
}
function nativeBindWriteRegion( elems = false ){
elems = elems || selectAllElems( '.native_receiver' );
if( !elems ){
// No element exists, abort
return false;
}else if( elems.outerHTML ){
// if only a single element, put in array
elems = [ elems ];
}
// else it is html-collection
for( let i = 0 ; i < elems.length ; i++ ){
elems[i].ondragover = function(e){
e.preventDefault();
return false;
};
elems[i].ondrop = function(e){
receiveBlock(e);
};
}
}
function receiveBlock(e){
e.preventDefault();
let content = window.inTransferMarkup;
window.inTransferMarkup = "";
let range = null;
if (document.caretRangeFromPoint) { // Chrome
range = document.caretRangeFromPoint(e.clientX, e.clientY);
}else if (e.rangeParent) { // Firefox
range = document.createRange();
range.setStart(e.rangeParent, e.rangeOffset);
}
let sel = window.getSelection();
sel.removeAllRanges();
sel.addRange( range );
e.target.focus();
document.execCommand('insertHTML',false, content);
sel.removeAllRanges();
// reset draggable on all blocks, esp the recently created
nativeBindDraggable(
document.querySelector(
`[data-transferreference='${window.transferreference}']`
)
);
removeElem( selectElem( '.dragged' ) );
return false;
}
nativeBindDraggable();
nativeBindWriteRegion();
<div class="native_receiver" style="border: 2px solid red;padding: 5px;" contenteditable="true" >
WAITING FOR STUFF
</div>
<div class="drawer" style="border: 2px solid #AAE46A; padding: 10px">
<span class="native_drag" data-type="dateselector" contenteditable="false" draggable="true" style="border: 2px solid rgba(0,0,0,0.2);padding:4px; margin:2px">
Block 1
</span>
<span class="native_drag" data-type="dateselector" contenteditable="false" draggable="true" style="border: 2px solid rgba(0,0,0,0.2);padding:4px; margin:2px">
Second Blk
</span>
</div>
event dragstart; dataTransfer.setData("text/html", "<div class='whatever'></div>");
event drop:
var me = this; setTimeout(function () {
var el = me.element.getElementsByClassName("whatever")[0];
if (el) { //do stuff here, el is your location for the fancy img
}
}, 0);
To summarise above answers, the keys are event.parentNode and event.rangeOffset (firefox) and caretRangeFromPoint(event.clientX, event.clientY) (chrome).
Here is a minimal example:
span {
border: 1px solid red;
}
span:before {
content: "grab ";
background-color: #0f0;
}
<p contenteditable="true"
ondrop="sel = window.getSelection();
if (document.caretRangeFromPoint)
range = document.caretRangeFromPoint(event.clientX, event.clientY)
else {
sel.collapse(event.rangeParent,event.rangeOffset)
range = sel.getRangeAt(0)
}
range.insertNode(sp1)"
ondragover="
return false"
>This is a contenteditable paragraph. Grab the green field in the following span
<span draggable="True" id="sp1" ondragstart="
event.dataTransfer.setData('text/plain', this.innerText)">span</span>
and drag it inside this paragraph.
</p>
Related
I'm writing a small notetaking webapp which uses CKEditor as a HTML editor. I've been able to integrate it well, with one exception - drag and drop functionality. It mostly works - but there are two quirks I haven't been able to solve despite trying a whole lot of different approaches.
My requirements are simple - I drag any file into CKEditor from outside the app, upon which it should insert a simple anchor tag in the editable text with a local link to the file. Currently, I am implementing drag and drop in my own CKEditor plugin called filemanager:
CKEDITOR.plugins.add( 'filemanager', {
init: function( editor ) {
editor.on('contentDom', function(contentDom) {
//Runs upon dropping a file into the editor
contentDom.editor.document.on('drop', function(e) {
//prevents default behavior as long as it's an actual file drag and drop (if it's dragging text etc. inside the editor, keep default behavior)
if(e.data.$.dataTransfer.files.length)
{
e.data.preventDefault();
}
//Goes through all the dropped files and insert HTML with links
for (var i = 0; i < e.data.$.dataTransfer.files.length; ++i) {
CopyData(e.data.$.dataTransfer.files[i].path);
}
});
});
//Creates the link in the editor
function CopyData(path, range)
{
//Link HTML
var fileHTML;
/* Code to parse the path into HTML to be inserted */
editor.insertHtml(fileHTML);
}
}
});
I have omitted most of the CopyData function as the formatting isn't relevant, but it generates a div such as this:
fileHTML = ""+fileName+"";
This does work perfectly fine, so the basic implementation of the feature seems to work. However, here are my two issues:
Dropping a file into the editor but outside the actual text area (such as below the final line of text in the editor) does not disable default behavior. How can I run a preventDefault() for this area of the editor? Been trying events in all sort of places without results.
The HTML isn't inserted at the location of the mouse cursor, even though CKEditor previews a caret there. Rather, it is inserted where the caret currently is in the document, independently of where you drop. This disrupts core functionality of the feature - is there a way to insert HTML at the mouse position? I would assume so since CKEditor actually previews a caret where the mouse is, but I looked through the documentation without results.
Does anyone have ideas of how to solve the two above issues? If it helps, I am using nw.js so the webapp will always run in Chromium. Grateful for any responses!
I eventually managed to solve these issues.
To prevent default behavior outside the DOM elements, I added this code to my CKEditor plugin:
var iframeWin = window.document.getElementsByTagName('iframe')[0].contentWindow;
iframeWin.addEventListener("dragover",function(e){
e = e || iframeWin.event;
if(e.dataTransfer.files.length)
{
e.preventDefault();
}
},false);
iframeWin.addEventListener("drop",function(e){
e = e || iframeWin.event;
if(e.dataTransfer.files.length)
{
e.preventDefault();
}
},false);
This correctly identified the iframe I needed to disable default behavior in. The if(e.dataTransfer.files.lenght) condition makes sure this only applies to files dragged into the app, and not dragging things within the editor.
Inserting the HTML at the mouse cursor was trickier! This cannot be credited to me - I found a function doing most of the work on the CKEditor bug tracker, and edited it to work in this scenario:
function moveSelectionToDropPosition( editor, dropEvt )
{
var $evt = dropEvt.data.$,
$range,
range = editor.createRange();
// Make testing possible.
if ( dropEvt.data.testRange ) {
dropEvt.data.testRange.select();
return;
}
// Webkits.
if ( document.caretRangeFromPoint ) {
$range = editor.document.$.caretRangeFromPoint( $evt.clientX, $evt.clientY );
range.setStart( CKEDITOR.dom.node( $range.startContainer ), $range.startOffset );
range.collapse( true );
}
// FF.
else if ( $evt.rangeParent ) {
range.setStart( CKEDITOR.dom.node( $evt.rangeParent ), $evt.rangeOffset );
range.collapse( true );
}
// IEs.
else if ( document.body.createTextRange ) {
$range = editor.document.getBody().$.createTextRange();
$range.moveToPoint( $evt.clientX, $evt.clientY );
var id = 'cke-temp-' + ( new Date() ).getTime();
$range.pasteHTML( '<span id="' + id + '">\u200b</span>' );
var span = editor.document.getById( id );
range.moveToPosition( span, CKEDITOR.POSITION_BEFORE_START );
span.remove();
}
range.select();
}
In the drop event I then simply added
moveSelectionToDropPosition(editor, e);
And it all worked as intended!
Hopefully this may help anyone else having similar issues in the future :)
Knowing the jQuery Caret plugin, I'm still seeing no way to do the following on a single line text box in HTML (i.e. the input:type=text control) with JavaScript:
Programmatically inserting text into a text box
Setting the caret to the end.
Making the caret visible (i.e. scroll the text box content)
I know how to do 1. and 2., just for 3. I have found no way of doing it.
To illustrate it:
My question is:
Is there any way to reliable put the caret at the end of the text and scroll it into the view?
(I can think of simulating pressing the END key or something like that, but I'm unsure whether this would be the best option).
You could try triggering a right key press after focus.
$('#textbox').focus();
var e = jQuery.Event("keydown");
e.which = 39; // aka right arrow.
$("input").trigger(e);
//hack to get cursor at end:
$(textboxselector).val($(textboxselector).val());
edit: should note focus first:
$(textboxselector).val(newtext);
$(textboxselector).focus();
$(textboxselector).val($(textboxselector).val());
It's not possible to implement this behavior cross-browser. FireFox supports the KeyboardEvent.initKeyPress method, which allows key events to be simulated.
See the comments at the function below for an explanation. I've successfully tested this function in FireFox 3.6.22, 7.0.1 and Chrome 14.
The function itself is plugin-independent. Fiddle: http://jsfiddle.net/Jskbb/1/
/* #name caretAtEnd
* #description Places caret at the end
* #param elem DOM element
* #param focus boolean, optional. If true, the element will be focused.
*/
function caretAtEnd(elem, focus){
var value = elem.value;
//Add an extra character to the input field (necessary for this method)
// An additional advantage is that the caret automatically moves to the end
elem.value = elem.value + ".";
try {
// Create and simulate/trigger a [Backspace] keypress event.
var evt = document.createEvent("KeyboardEvent");
evt.initKeyEvent("keypress", 1, 1, null, 0, 0, 0, 0, 8, 0);
elem.dispatchEvent(evt);
} catch(e){
//The current key event is not supported yet. Change back the value
// In some browsers, the caret is at the end after executing this code.
elem.value = value;
}
//Optionally, Focus on the element
if(focus) elem.focus();
}
var element = $("#yourInputElement")[0]; //Important: Get the DOM element!
caretAtEnd(element);
So with the help of Mark and Rob W, I finally managed to solve it.
My additional challenge was that the text box already has the focus, which came out is an issue (I'm using the whole stuff in the OnClientItemSelected of the Ajax Toolkit's AutoCompleteExtender).
So my solution is:
<ajaxToolkit:AutoCompleteExtender
runat="server"
ID="EMailTextBoxControlAutoCompleteExtender"
...
OnClientItemSelected="function() {
// Read current text and append some string.
var tbSel = '#EMailTextBoxControl';
var newText = $(tbSel).val() + ', ';
// Since we already have the focus,
// remove it and set it to another control.
$('#AdditionalRemarksControl').focus();
// https://stackoverflow.com/questions/7892902/7903519#7903519
$(tbSel).val(newText);
$(tbSel).focus();
$(tbSel).val($(tbSel).val());
}">
It's working for me successfully in Google Chrome, Firefox and Internet Explorer 9. Hopefully it works in other browsers, too.
I'm marking Mark's comment as the answer.
try to set the scrollLeft property of the input, as:
input.scrollLeft = 10000;
You can use scrollWidth to get a better guess on the final value, but using a high one can ensure correctness on most cases.
If you want to put the caret at the end and scroll to the bottom of a textarea, this works perfectly :
function moveCaretToEnd(el) {
if (typeof el.selectionStart == "number") {
el.selectionStart = el.selectionEnd = el.value.length;
} else if (typeof el.createTextRange != "undefined") {
el.focus();
var range = el.createTextRange();
range.collapse(false);
range.select();
}
setTimeout(function(){
var pos = $(el).offset().top + $(el).height();
$('html, body').animate({
scrollTop: pos
}, 1000);
},100);
}
moveCaretToEnd(document.getElementById("replyBox"));
It will place the caret at the end, and then smoothly scroll the window to the bottom.
I am writing a simple little piece of code to draw pixels wherever the mouse is in a box. I also want to have a clear button. Drawing works fine, but I can't seem to get the clear button to work. Here are the relevant parts of my .js file:
function pixel(x, y) {
var pix = document.createElement("div");
pix.setAttribute("style", "position:absolute;left:" + x + "px;top:" +
y + "px;width:3px;height:3px;background:#000;cursor:crosshair");
return pix;
}
var mouseDown = false;
function draw(event) {
if (!mouseDown) return;
var x = event.clientX;
var y = event.clientY;
document.getElementById("box").appendChild(pixel(x, y));
}
/* Neither 1, 2, nor 3 work! */
function clear() {
var box = document.getElementById("box");
/* 1 */
// box.innerHTML = "";
/* 2 */
// box.childNodes = new NodeList();
/* 3 */
for (n in box.childNodes)
box.removeChild(n);
}
The relevant part of my HTML file is:
<body onmousedown="mouseDown=true" onmouseup="mouseDown=false">
<div id="box" onmouseover="document.getElementById('box').style.cursor='crosshair'"
onmousemove="draw(event)"></div>
<button onclick="clear()">Clear</button>
</body>
The box is also formatted a bit with CSS but that shouldn't be an issue. I feel like the problem might be that I'm deleting the pixels from the box but not from the document or something, but I'm a JavaScript noob so I don't know.
Rename your function to something else (not clear()).
function removePixels() {
var box = document.getElementById("box");
if (box.hasChildNodes() )
{
while ( box.childNodes.length >= 1 )
{
box.removeChild( box.firstChild );
}
}
}//end function
I don't think clear is a valid name for a function.
http://jsfiddle.net/zUJ2e/
EDIT: Yep, definitely not
http://www.roseindia.net/javascript/javascript-clear-method.shtml
You shouldn't use a "for ... in" loop on a NodeList:
for (var n = 0; n < childNodes.length; ++n)
box.removeChild(childNodes[n]);
A NodeList isn't an Array, though it sort-of acts like one, sometimes. In general, "for ... in" is for objects, not Arrays.
Another, totally separate note: you may run into problems on some browsers setting the "style" that way (for your "pixels"). The "style" property of a DOM node is treated as a weird magic thing in all browsers, but my recollection is that doing what you're doing may not always work. Instead, you would set individual properties of someElement.style.
The way that you're hooking up for your button to the event handler is inadvertently hitting document.clear(), rather than the clear() function that you've defined.
One way to avoid this is to rename the function to something else. If you rename the function to myClear(), for example, that should resolve this particular conflict. This does feel a bit dodgy, however.
You can bind your event-handler in JavaScript itself, which seems more reliable. If you're using the JQuery library, you can do something like this, for example:
// when the document is ready...
$(document).ready(function() {
// connect all buttons to the clear event handler.
$('button').click(clear);
})
If you're trying to stick with vanilla JavaScript, you can set the onclick attribute in JavaScript, when the DOM tree is mostly ready.
<body onmousedown="mouseDown=true" onmouseup="mouseDown=false">
<div id="box" onmouseover="document.getElementById('box').style.cursor='crosshair'"
onmousemove="draw(event)"></div>
<!-- button has an id to make it selectable with getElementById() -->
<button id="button">Clear</button>
<!-- Placed at the bottom so we have a chance of getting button -->
<script>
document.getElementById("button").onclick = clear;
</script>
</body>
I have a <p> containing text. When the <p> is clicked on, I create a <textarea> containing the text from the <p>. Is it possible to calculate where in the <p>'s text the click occurred, and move the <textarea>'s cursor to that same point?
I don't believe so, no. The DOM just knows what containing element received the click event, it doesn't distinguish between pieces of text within the containing element unless they are elements themselves. And I doubt you want to wrap every character in your text with its own element tag :)
Hope this simple example helps:
<html>
<head/>
<body>
<script type='text/javascript'>
function getPosition()
{
var currentRange=window.getSelection().getRangeAt(0);
return currentRange.endOffset;
}
function setPosition(elemId, caretPos) {
var elem = document.getElementById(elemId);
if(elem != null) {
if(elem.createTextRange) {
var range = elem.createTextRange();
range.move('character', caretPos);
range.select();
}
else {
if(elem.selectionStart) {
elem.focus();
elem.setSelectionRange(caretPos, caretPos);
}
else
elem.focus();
}
}
}
function test()
{
setPosition('testId', getPosition());
}
</script>
<p onclick = 'test()'>1234567890</p>
<textarea id='testId'>123467890</textarea>
</body>
</html>
Or you can use third-party JS library like jQuery - see this example.
I'm guessing this is going to take a fair amount of fiddling to get right, and you won't be able to get it exactly right. But you'll probably want to use event.clientX and event.clientY.
EDIT -- didn't know about this stuff when I replied. Looks pretty possible to get it exactly correct.
http://www.quirksmode.org/dom/range_intro.html
An alterntive idea: style the textarea so it looks like plain text, and re-style it to look like a form field when it gets clicked.
I have a textarea and a button on a form. The textarea may already have some text in it. I would like the cursor to move to the last position in the text area when the button is clicked.
Is this possible?
xgMz's answer was best for me. You don't need to worry about the browser:
var html = $("#MyTextArea").val();
$("#MyTextArea").focus().val("").val(html);
And here's a quick jQuery extension I wrote to do this for me next time:
; (function($) {
$.fn.focusToEnd = function() {
return this.each(function() {
var v = $(this).val();
$(this).focus().val("").val(v);
});
};
})(jQuery);
Use like this:
$("#MyTextArea").focusToEnd();
By “the last position”, do you mean the end of the text?
Changing the ‘.value’ of a form field will move the cursor to the end in every browser except IE. With IE you have to get your hands dirty and deliberately manipulate the selection, using non-standard interfaces:
if (browserIsIE) {
var range= element.createTextRange();
range.collapse(false);
range.select();
} else {
element.focus();
var v= element.value();
element.value= '';
element.value= v;
}
Or do you mean put the cursor back to the place it was previously, the last time the textarea was focused?
In every browser except IE, this will already happen just by calling ‘element.focus()’; the browser remembers the last cursor/selection position per input and puts it back on focus.
This would be quite tricky to reproduce in IE. You would have to poll all the time to check where the cursor/selection was, and remember that position if it was in an input element, then fetch the position for a given element when the button was pressed and restore it. This involves some really quite tedious manipulation of ‘document.selection.createRange()’.
I'm not aware of anything in jQuery that would help you do this, but there might be a plugin somewhere perhaps?
You can also do this:
$(document).ready(function()
{
var el = $("#myInput").get(0);
var elemLen = el.value.length;
el.selectionStart = elemLen;
el.selectionEnd = elemLen;
el.focus();
});
This code works for both input and textarea. Tested with latest browsers: Firefox 23, IE 11 and Chrome 28.
jsFiddle available here: http://jsfiddle.net/cG9gN/1/
Source: https://stackoverflow.com/a/12654402/114029
You could use this https://github.com/DrPheltRight/jquery-caret
$('input').caretToEnd();
This is what I use for textareas inside my onclick or other events and seems to work fine for FireFox and IE 7 & 8. It positions the cursor at the end of the text instead of the front.
this.value = "some text I want to pre-populate";
this.blur();
this.focus();
To set mouse focus and move cursor to end of input. Its work in every browser, Its just simple logic here.
input.focus();
tmpStr = input.val();
input.val('');
input.val(tmpStr);
I modified #mkaj extension a little to support default value
; (function($) {
$.fn.focusToEnd = function(defaultValue) {
return this.each(function() {
var prevValue = $(this).val();
if (typeof prevValue == undefined || prevValue == "") {
prevValue = defaultValue;
}
$(this).focus().val("").val(prevValue);
});
};
})(jQuery);
// See it in action here
$(element).focusToEnd("Cursor will be at my tail...");