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Dropping image to a div removes it from the previous div

I have made this
https://jsfiddle.net/a4376mr8/
When I drag and drop the image div to a new div, why is it not there in the previous div?
const boxes = document.querySelectorAll('.box');
const imageBox = document.querySelector('#draggableItem');
for (const box of boxes) {
box.addEventListener('dragover', function (e) {
e.preventDefault();
this.className += ' onhover';
})
box.addEventListener('dragleave', function () {
this.className = 'box';
})
box.addEventListener('drop', function (e) {
this.className = 'box';
this.append(imageBox);
})
}

If I understood your needs, that the image be repeated on drag and drop, you need to clone your div tag dom object. Since js just sees the reference to it, when you simply append it, this causes it to just move from place to place instead of duplicating.
So instead of just appending, clone the node as follows (line 15 of your fiddle's js).
this.append(imageBox.cloneNode(true));
See here: https://developer.mozilla.org/en-US/docs/Web/API/Node/cloneNode
Updated fiddle: https://jsfiddle.net/a4376mr8/1/

Event listener fails to attach or remove in some contexts

I've created a script that attaches an event listener to a collection of pictures by default. When the elements are clicked, the listener swaps out for another event that changes the image source and pushes the id of the element to an array, and that reverses if you click on the swapped image (the source changes back and the last element in the array is removed). There is a button to "clear" all of the images by setting the default source and resetting the event listener, but it doesn't fire reliably and sometimes fires with a delay, causing only the last element in a series to be collected.
TL;DR: An event fires very unreliably for no discernible reason, and I'd love to know why this is happening and how I should fix it. The JSFiddle and published version are available below.
I've uploaded the current version here, and you can trip the error by selecting multiple tables, pressing "Cancel", and selecting those buttons again. Normally the error starts on the second or third pass.
I've also got a fiddle.
The layout will be a bit wacky on desktops and laptops since it was designed for phone screens, but you'll be able to see the issue and inspect the code so that shouldn't be a problem.
Code blocks:
Unset all the selected tables:
function tableClear() {
//alert(document.getElementsByClassName('eatPlace')[tableResEnum].src);
//numResTables = document.getElementsByClassName('eatPlace').src.length;
tableArrayLength = tableArray.length - 1;
for (tableResEnum = 0; tableResEnum <= tableArrayLength; tableResEnum += 1) {
tableSrces = tableArray[tableResEnum].src;
//alert(tableSrcTapped);
if (tableSrces === tableSrcTapped) {
tableArray[tableResEnum].removeEventListener('click', tableUntap);
tableArray[tableResEnum].addEventListener('click', tableTap);
tableArray[tableResEnum].src = window.location + 'resources/tableBase.svg';
} /*else if () {
}*/
}
resTableArray.splice(0, resTableArray.length);
}
Set/Unset a particular table:
tableUntap = function () {
$(this).unbind('click', tableUntap);
$(this).bind('click', tableTap);
this.setAttribute('src', 'resources/tableBase.svg');
resTableArray.shift(this);
};
tableTap = function () {
$(this).unbind('click', tableTap);
$(this).bind('click', tableUntap);
this.setAttribute('src', 'resources/tableTapped.svg');
resTableArray.push($(this).attr('id'));
};
Convert the elements within the 'eatPlace' class to an array:
$('.eatPlace').bind('click', tableTap);
tableList = document.getElementsByClassName('eatPlace');
tableArray = Array.prototype.slice.call(tableList);
Table instantiation:
for (tableEnum = 1; tableEnum <= tableNum; tableEnum += 1) {
tableImg = document.createElement('IMG');
tableImg.setAttribute('src', 'resources/tableBase.svg');
tableImg.setAttribute('id', 'table' + tableEnum);
tableImg.setAttribute('class', 'eatPlace');
tableImg.setAttribute('width', '15%');
tableImg.setAttribute('height', '15%');
$('#tableBox').append(tableImg, tableEnum);
if (tableEnum % 4 === 0) {
$('#tableBox').append("\n");
}
if (tableEnum === tableNum) {
$('#tableBox').append("<div id='subbles' class='ajaxButton'>Next</div>");
$('#tableBox').append("<div id='cazzles' class='ajaxButton'>Cancel</div>");
}
}

First mistake is in tapping and untapping tables.
When you push a Table to your array, your pushing its ID.
resTableArray.push($(this).attr('id'));
It will add id's of elements, depending on the order of user clicking the tables.
While untapping its always removing the first table.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/shift
resTableArray.shift(this);
So, when user clicks tables 1, 2, 3. And unclicks 3, the shift will remove table 1.
Lets fix this by removing untapped table
tableUntap = function () {
$(this).unbind('click', tableUntap);
$(this).bind('click', tableTap);
this.setAttribute('src', 'http://imgur.com/a7J8OJ5.png');
var elementID = $(this).attr('id');
var elementIndex = resTableArray.indexOf(elementID);
resTableArray.splice(elementIndex, 1);
};
So you were missing some tables after untapping.
Well lets fix tableClear,
You have a array with tapped tables, but you are searching in main array.
function tableClear() {
tableLen = resTableArray.length;
for (var i = 0; i < tableLen; i++) {
var idString = "#" + resTableArray[i];
var $element = $(idString);
$element.unbind('click', tableUntap);
$element.bind('click', tableTap);
$element.attr("src", 'http://imgur.com/a7J8OJ5.png');
}
resTableArray = [];
}
Im searching only tapped tables, and then just untap them and remove handlers.
fiddle: http://jsfiddle.net/r9ewnxzs/
Your mistake was to wrongly remove at untapping elements.

Kendo grid cell refocusing after refresh

I have a selectable, navigatable and editable grid. After I enter a value in a cell, I have to change the value in the cell under the updated cell. To show the updated values of both cells, I have to refresh the grid. When I do that, the edited cell loses focus. I found a way to refocus the last edited cell during the save event:
save: function (e) {
var focusedCellIndex = this.current()[0].cellIndex; //gets the cell index of the currently focused cell
//...some dataItem saving (dataItem.set()) logic...
this.refresh(); //refreshing the grid instance
setTimeout(function () { //refocusing the cell
return function () {
var focusedCell = $("#grid tr[data-uid='" + dataItem.uid + "'] td:nth-child(" + (focusedCellIndex + 1) + ")");
$('#grid').data('kendoGrid').editCell(focusedCell);
}
}(), 200);
}
The problem is that this works for the first time, but if I try to re-edit the same cell again, the cell loses focus. When I try to debug, it seems that this.current()[0].cellIndex returns 0 in the second attempt, and because of that cell focusing isn't working anymore.
Does anyone have any idea why this.current() works for the 1st time, and not for the 2nd time? Are there any other approaches for refocusing the cell?

It's difficult to say exactly what is happening without seeing it in a demo, so if you can, I'd suggest creating one for illustration. I'm guessing that the call to refresh is removing the current cell selection and focusing the first cell because the grid is navigatable (I don't quite understand the rationale behind that behavior, but it's hard to say whether it's a bug since we don't get to read Telerik's code comments).
One approach that might work would be to modify the current method to also store the current cell index:
kendo.ui.Grid.fn.refresh = (function(refresh) {
return function(e) {
this._refreshing = true;
refresh.call(this, e);
this._refreshing = false;
}
})(kendo.ui.Grid.fn.refresh);
kendo.ui.Grid.fn.current = (function(current) {
return function(element) {
// assuming element is td element, i.e. cell selection
if (!this._refreshing && element) {
this._lastFocusedCellIndex = $(element).index(); // note this might break with grouping cells etc, see grid.cellIndex() method
this._lastFocusedUid = $(element).closest("tr").data("uid");
}
return current.call(this, element);
}
})(kendo.ui.Grid.fn.current);
kendo.ui.Grid.fn.refocusLastEditedCell = function () {
if (this._lastFocusedUid ) {
var row = $(this.tbody).find("tr[data-uid='" + this._lastFocusedUid + "']");
var cell = $(row).children().eq(this._lastFocusedCellIndex);
this.editCell(cell);
}
};
That way, you should always be able to use grid.refocusLastEditedCell() when you need to.
Another idea:
save: function (e) {
var focusedCell = this.current();
var focusedCellIndex = focusedCell.index(); //gets the cell index of the currently focused cell
//...some dataItem saving (dataItem.set()) logic...
this.refresh(); //refreshing the grid instance
// reset current cell..
this.current(focusedCell);
setTimeout(function () { //refocusing the cell
return function () {
var focusedCell = $("#grid tr[data-uid='" + dataItem.uid + "'] td:nth-child(" + (focusedCellIndex + 1) + ")");
$('#grid').data('kendoGrid').editCell(focusedCell);
}
}(), 200);
}

I don't have enough reputation to comment on the answer, but I'd like to thank you Lars Hoppner for your answer. It helped me tremendously with the annoying refresh navigation problems of Kendo Grids.
I also would like to add that for grids with horizontal scroll bars, your solution will still cause the scroll to shift as far left as possible while keeping the last edited cell in view. To prevent this bad behavior, I did the following:
grid.closeCell();
grid.refresh();
grid.refocusLastEditedCell();
Closing the cell before refreshing kept the scroll bars in place, now everything works great. Hopefully this helps anyone else viewing your answer.

exchanging values in a select list with jQuery

I'm trying to swap select option values with jQuery when a links clicked, at the moment its just resetting the select when the links clicked, not sure what's going wrong?:
jQuery:
$(function () {
$("#swapCurrency").click(function (e) {
var selectOne = $("#currency-from").html();
var selectTwo = $("#currency-to").html();
$("#currency-from").html(selectTwo);
$("#currency-to").html(selectOne);
return false;
});
});
JS Fiddle here: http://jsfiddle.net/tchh2/

I wrote it in a step-by-step way so it is easier to understand:
$("#swapCurrency").click(function (e) {
//get the DOM elements for the selects, store them into variables
var selectOne = $("#currency-from");
var selectTwo = $("#currency-to");
//get all the direct children of the selects (option or optgroup elements)
//and remove them from the DOM but keep events and data (detach)
//and store them into variables
//after this, both selects will be empty
var childrenOne = selectOne.children().detach();
var childrenTwo = selectTwo.children().detach();
//put the children into their new home
childrenOne.appendTo(selectTwo);
childrenTwo.appendTo(selectOne);
return false;
});
jsFiddle Demo
Your approach works with transforming DOM elements to HTML and back. The problem is you lose important information this way, like which element was selected (it is stored in a DOM property, not an HTML attribute, it just gives the starting point).
children()
detach()
appendTo()

That happens because you remove all elements from both <select> fields and put them as new again. To make it working as expected you'd better move the actual elements as follows:
$("#swapCurrency").click(function(e) {
var options = $("#currency-from > option").detach();
$("#currency-to > option").appendTo("#currency-from");
$("#currency-to").append(options);
return false;
});
DEMO: http://jsfiddle.net/tchh2/2/

You are replacing the whole HTML (every option) within the <select>. As long as each select has the same amount of options and they correspond to each other, you can use the selected index property to swap them:
$("#swapCurrency").click(function (e) {
var selOne = document.getElementById('currency-from'),
selTwo = document.getElementById('currency-to');
var selectOne = selOne.selectedIndex;
var selectTwo = selTwo.selectedIndex;
selOne.selectedIndex = selectTwo;
selTwo.selectedIndex = selectOne;
return false;
});
JSFiddle

Delete current parent node in recursion

I created multiple divs which class="extra". Then I add delete buttons to each div in order to remove each div respectively. So my code is:
var exr = document.getElementsByClassName("extra");
for(var i = 0 ;i<exr.length;i++){
var delbt = document.createElement("button");
delbt.className="floatbutton_3 font_b"
delbt.innerHTML="delete";
exr[i].appendChild(delbt);
delbt.onclick= function(i){ return function(){ exr[i].parentNode.removeChild(exr[i]) } }(i);
}
The problem is, the button can't removethe button it should remove. It seems that after last delete, the index is changed. How to avoid this from happening?
Thanks!

Use this within the onclick function to reference the button that was clicked — so by replacing excr[i] with this.parentNode, your code should execute as intended.

Do this...
var exr = document.getElementsByClassName("extra");
for(var i = 0 ;i<inserter.length;i++){
var delbt = document.createElement("button");
delbt.className="floatbutton_3 font_b"
delbt.innerHTML="delete";
exr[i].appendChild(delbt);
delbt.index = i;
delbt.onclick= function(i){ var me = this; return function(){ exr[me.index].parentNode.removeChild(exr[i]) } }(i);
}

Since getElementsByClassName() returns a live set, you could make a shallow copy first:
var exr = [].slice.call(document.getElementsByClassName("extra"), 0);

You could use currentTarget on the click event.
This will only remove the parent div of the button clicked.
var exr = document.getElementsByClassName("extra");
for(var i = 0 ;i<exr.length;i++){
var delbt = document.createElement("button");
delbt.className="floatbutton_3 font_b"
delbt.innerHTML="delete";
exr[i].appendChild(delbt);
delbt.onclick= function( event ){
event.currentTarget.parentElement.remove();
}
}

The code looks like it should work, but only as long as you don't add or remove elements. And that's what you are doing.
There is a simpler and more reliable solution: You can use this inside the event handler to refer to the current element.
delbt.onclick = function() {
var div = this.parentNode; // you want to remove the div, not the button
div.parentNode.removeChild(div);
};
I recommend to read the excellent articles about event handling on quirksmode.org, especially about traditional event handling (since that's what you are using).

getElementsByClassName() returns an HTMLCollection. This is a live list that changes when the underlying structure changes. So even if you don't activly delete the elements from the list, they still will be removed from it automatically when you remove the corresponding HTML Element.
By passing i to the anonymous function, you kind of fixed the index. So whenever you click on the third delete button it will try to delete the third element in the list. But if you have already deleted the first and the second element, the list will be modified too. So your third button will be represented by the first item in your list but it will try to find the third one.
To avoid this problem you can pass the complete element to the anonymous function and not just the index:
for(var i = 0 ;i<exr.length;i++){
var delbt = document.createElement("button");
delbt.className="floatbutton_3 font_b"
delbt.innerHTML="delete";
exr[i].appendChild(delbt);
delbt.onclick = function(el){ return function(){ el.parentNode.removeChild(el) } }(exr[i]);
}

I'll add a jQuery solution:
$('.extra').append(function() {
return $('<button />', {'class':'floatbutton_3 font_b', html:'delete'});
});
$('.floatbutton_3').on('click', function() {
$(this).closest('div').remove();
});
FIDDLE