The on click event that I add to an input in javascript isn't working in the proper manner.
My code so far looks like so:
function order(option) {
if(option.checked) {
document.getElementId("col_order").value = document.getElementById("col_order").value + " " + option.value;
}
}
...//somewhere further down
for(var i = 0; i < options.length; i++) {
var check = document.createElement("input");
var label = document.createElement("label");
var description = document.createTextNode(options[i]);
check.type = "checkbox";
check.name = "order_list[]";
check.value = options[i];
check.onclick = "order(check)"; //Problem here
label.appendChild(check);
label.appendChild(description);
element.appendChild(label);
}
I have also tried:
check.onclick = (function() { var option = check; return function() {order(option);}})();
The problem that I am having is the check.onlick line of code. When I add this with normal HTML:
<input type = "checkbox" name = "order_list[]" onclick = "order(this)" value = "randVal">randVal</input>
I don't have any problem whatsoever; the method executes with the intended results. Any thoughts?
Let me clarify: I make it to the order function just fine, but I never get into the if statement, even though the checkbox was just clicked
Use addEventListener instead, and even if it looks like it should work, you're overwriting the same variables on each iteration as there is no closure in for loops, so I would probably add a closure to avoid issues.
For a checkbox you would listen for the change event, not click
for(var j = 0; j < options.length; j++) {
(function(i) {
var check = document.createElement("input");
var label = document.createElement("label");
var description = document.createTextNode(options[i]);
check.type = "checkbox";
check.name = "order_list[]";
check.value = options[i];
check.addEventListener('change', function() {
if (this.checked) {
var col_order = document.getElementById("col_order");
col_order.value = col_order.value + " " + this.value;
}
}, false);
label.appendChild(check);
label.appendChild(description);
element.appendChild(label);
})(j);
}
FIDDLE
check.onclick = "order(check)"; assigns a String as an on-click handler. That doesn't work; the browser expects a function there:
check.onclick = function() {
order(check);
}
Related
*This is happening inside a larger block of code, in a for loop. See end of post for entire loop.
I've read all of the posts that seem to be about this subject, but I'm still lost.
I'm trying to assign an onclick event to a checkbox. The function being assigned to the onclick event needs to have access to a variable that is available in the scope where the checkbox is defined (idvariable).
var idvariable = parentChildList[i].children[j]["subjectid"];
var input = document.createElement("input");
input.type = "checkbox";
input.value = "";
input.onclick = function () {
return clicked(idvariable);
};
function clicked(id) {
alert(id);
};
I've tried every variation of inline and named functions, but I can't figure out how to give the clicked function access to idvariable. In this example above, the value of that variable is undefined.
Or, if I try it with this way:
var input = document.createElement("input");
input.type = "checkbox";
input.value = "";
var idvariable = parentChildList[i].children[j]["subjectid"];
input.onclick = function (idvariable) {
return clicked(idvariable);
};
function clicked(id) {
alert(id);
};
I get an alert that says [object MouseEvent]. Same with the following where I removed the () from the method name I'm assigning to the onclick event:
var idvariable = parentChildList[i].children[j]["subjectid"];
input.onclick = function () {
return clicked;
}(idvariable);
function clicked(id) {
return alert(id);
};
*entire loop:
for (var i = 0; i < parentChildList.length; i++) {
var row = table1.insertRow(-1);
var cell = row.insertCell(0);
cell.innerHTML =
"<h4 class=\"panel-title\"><a data-toggle=\"collapse\" data-parent=\"#accordion\" href=\"#collapse" + i + "\">" + parentChildList[i]["title"] + "</a></h4>";
if (parentChildList[i].children.length > 0) {
var row2 = table1.insertRow(-1);
var cell2 = row2.insertCell(0);
var table2 = document.createElement("table");
table2.className = "collapse";
table2.id = "collapse" + i;
cell2.appendChild(table2);
for (var j = 0; j < parentChildList[i].children.length; j++) {
var row3 = table2.insertRow(-1);
var cell3 = row3.insertCell(0);
var div = document.createElement("div");
div.className = "checkbox";
var label = document.createElement("label");
label.innerText = parentChildList[i].children[j]["title"];
var input = document.createElement("input");
input.type = "checkbox";
input.value = "";
input.setAttribute('subj', idvariable);
var idvariable = parentChildList[i].children[j]["subjectid"];
alert(idvariable);
input.onclick = function () {
return clicked(this.getAttribute('subj'));
};
function clicked(id) {
return alert(id);
};
cell3.style.padding = "0px 0px 0px 10px";
cell3.style.fontsize = "x-small";
cell3.appendChild(div);
div.appendChild(label);
label.insertBefore(input, label.childNodes[0]);
}
}
}
onclick handler receives Event object. If a handler attached as elem.onclick=handler then the element is available inside the handler as this. So this is workaround.
var idvariable = parentChildList[i].children[j]["subjectid"];
var input = document.createElement("input");
input.type = "checkbox";
input.value = "";
input.setAttribute('data-subj', idvariable);
input.onclick = function () {
return clicked(this.getAttribute('data-subj'));
};
function clicked(id) {
alert(id);
};
You will have to append the checkbox to some existing element first, using the following code.
var element = document.getElementById("one").appendChild(input);
Then you can get the parent by using something like the following...
var x = document.getElementById("someId").parentElement;
where x will contain the parent element.
This link https://stackoverflow.com/a/9418326/886393 is about custom data in an event (custom event). Hope that helps.
Thanks
Paras
I'm creating a javascript function that builds a table with checkboxes.
I want associate a click event to them.
The event must be the same for all.
This is a part of my code:
var i = 0;
for (i = 0; i < data.Items.length; i++) {
var tr = $(document.createElement('tr'));
tr.addClass("MyBookings_table_content");
$("#MyBookings_table").append(tr);
//Create a CheckBox Element
var chkbox = document.createElement('input');
chkbox.type = "checkbox";
chkbox.id = "chk"+i.toString();
chkbox.name = "chk" + i.toString();
//Event here
}
Can anybody help me?
Since you are using jQuery, you can simply add this event listener :
$("#MyBookings_table").on("click", "input[type=checkbox]", clickCB);
function clickCB() {
var $cbx = $(this);
// some code on my checkbox
}
This code is to be appended after the loop, see this fiddle : http://jsfiddle.net/6f79pd5y/
create a function and link it with an addEventListener
function outerFunction(){
}
checkbox.addEventListener('click', outerFunction);
addEventListener("click",myFunction);
where you have the comments
How about:
var i = 0;
for (i = 0; i < data.Items.length; i++) {
var tr = $(document.createElement('tr'));
tr.addClass("MyBookings_table_content");
$("#MyBookings_table").append(tr);
//Create a CheckBox Element
var chkbox = document.createElement('input');
chkbox.type = "checkbox";
chkbox.id = "chk"+i.toString();
chkbox.name = "chk" + i.toString();
//Event here
$(chkbox).click(function()
{
alert("Click!");
});
tr.append(chkbox);
}
A working example:http://jsfiddle.net/mpup12z5/
If you reorganise your element-creation to use jQuery also, you can bind the click-handler at the point of creation:
var i = 0;
for (i = 0; i < data.Items.length; i++) {
var tr = $(document.createElement('tr'));
tr.addClass("MyBookings_table_content");
$("#MyBookings_table").append(tr);
$('<input />', {
'type' : 'checkbox',
'id' : chk + i, // i will be converted to a string automatically
'name' : chk + i,
'click' : functionToCall // note: no parentheses, you want to
}); // call the function, not use its return value
}
Or:
var i = 0;
for (i = 0; i < data.Items.length; i++) {
var tr = $(document.createElement('tr'));
tr.addClass("MyBookings_table_content");
$("#MyBookings_table").append(tr);
$('<input />', {
'type' : 'checkbox',
'id' : chk + i, // i will be converted to a string automatically
'name' : chk + i,
'on' : {
'click' : functionToCall
}
});
}
But, it really is preferable to delegate the event-handling to the closest ancestor element, presumably the <table>, unless a specific property of the created <input /> should call a different function, or do something somewhat different.
I am trying to go through a select list with 200+ entries and click on each one. When an element is clicked on it executes a function selectCountry() which adds a line to a table. I want to have it create a table with every option selected. The page of interest is at: http://www.world-statistics.org/result.php?code=ST.INT.ARVL?name=International%20tourism,%20number%20of%20arrivals.
So far I have the following, but it doesn't seem to work:
var sel = document.getElementById('selcountry');
var opts = sel.options;
for(var opt, j = 0; opt = opts[j]; j++) {selectCountry(opt.value)}
I am trying to do this in the console in Chrome.
One of the most useful features of dev tools is that when you write the name of a function, you get back its source code. Here's the source code for the selectCountry function:
function selectCountry(select) {
if (select.value == "000") return;
var option = select.options[select.selectedIndex];
var ul = select.parentNode.getElementsByTagName('ul')[0];
var choices = ul.getElementsByTagName('input');
for (var i = 0; i < choices.length; i++)
if (choices[i].value == option.value) {
$("#selcountry:selected").removeAttr("selected");
$('#selcountry').val('[]');
return;
}
var li = document.createElement('li');
var input = document.createElement('input');
var text = document.createTextNode(option.firstChild.data);
input.type = 'hidden';
input.name = 'countries[]';
input.value = option.value;
li.appendChild(input);
li.appendChild(text);
li.onclick = delCountry;
ul.appendChild(li);
addCountry(option.firstChild.data, option.value);
$("#selcountry:selected").removeAttr("selected");
$('#selcountry').val('');
}
Your flaw is now obvious. selectCountry accepts the entire select element as an argument as opposed to the select's value (which is a terrible design but meh). Instead of passing the value of the element, change its index:
var sel = document.getElementById('selcountry');
var opts = sel.options;
for(var i = 0; i < opts.length; i++) {
sel.selectedIndex = i
selectCountry(sel)
}
i trie to generate dynamic Input fields with unique Ids but i stucked:
function addTxtBx(){
var txtBxHolder = document.getElementById('txtBoxHolder');
var newTxtBx = document.createElement('input');
newTxtBx.type = 'text';
var i=1;
//newTxtBx.id = document.getElementById("txtWaypoint"[i])
if(i<10){
newTxtBx.id = "txtWaypoint"+[i];
i++;
break;
}
txtBoxHolder.appendChild(newTxtBx);
}
i tried it with a for() but always got Id='name'9,
i know im an trainee. :)
I think so where you miss to loop it properly.
function addTextBox(ops) {
var no = document.getElementById('id1').value;
for (var i = 0; i < Number(no); i++) {
var text = document.createElement('input');
text.type = "text";
text.id = "txtWaypoint" + i; //id created dynamically
document.getElementById('divsection').appendChild(text);
}
}
Try it
So I have this piece of code:
window.onload = function () {make_buttons ('calc'); }
function make_buttons (id) {
console.log (id);
var input = document.createElement("INPUT");
document.getElementById(id).appendChild(input);
for (var i = 0;i < 10; i++){
var btn = document.createElement ("BUTTON");
var t = document.createTextNode (i);
btn.appendChild(t);
document.getElementById(id).appendChild(btn).onclick=document.getElementsByTagName("INPUT").value=i;
}
};
Now when I have created the button with the for loop, it should also have the onclick event attached to it which writes the current value of i into my input form.
Code I have written produces no errors but when the button is clicked, it simply does not do anything. Why is that?
New version:
window.onload = function () {make_buttons ('calc'); }
function make_buttons (id) {
var input = document.createElement("input");
input.type = 'text';
input.id = 'inp';
document.getElementById(id).appendChild(input);
for (var i = 0;i < 10; i++){
var btn = document.createElement ("button");
btn.id = i;
var txt = document.createTextNode (i);
btn.appendChild(txt);
var make_btn = document.getElementById(id).appendChild(btn);
make_btn.onclick = button_pressed (i);
}
};
function button_pressed (id) {
document.getElementById("inp").value += id;
};
Method document.getElementsByTagName() returns a NodeList collection that you should iterate through.
You need to go in loop through retrieved elements and assign the value attribute to each of them.
So that you can change
document.getElementById(id).appendChild(btn).onclick=document.getElementsByTagName("INPUT").value=i;
to something like this:
var id = 'my-form',
btn = document.createElement('input');
btn.type = 'button';
btn.value = 'Click me!';
btn.onclick = function() {
var inputs = document.getElementsByTagName('input');
// NodeList to Array if needed:
// var inputsArray = Array.prototype.slice.call(inputs);
for(var i = 0, l = inputs.length; i < l; i++) {
inputs[i].value = i;
}
return false;
};
document.getElementById(id).appendChild(btn);
DEMO #1
Update:
About your second question, yes it won't work in this way since at the time when your onclick event handler is called it's using the last value assigned to i variable. To avoid this you can just use closures.
For example,
HTML:
<form action="" id="my-form">
<input type="text" id="inp" />
</form>
JavaScript:
var btn,
input,
form,
createHandler;
input = document.getElementById('inp');
form = document.getElementById('my-form');
createHandler = function(i) {
return function() {
input.value += i;
};
};
for(var i = 0; i < 5; i++) {
btn = document.createElement('input');
btn.type = 'button';
btn.value = 'Append ' + i;
form.appendChild(btn);
btn.onclick = createHandler(i);
}
DEMO #2
Also you can use just immediately invoked anonymous function to create that closure in the body of your loop:
for(var i = 0; i < 5; i++) {
// ...
btn.onclick = (function(theNumberToAppend) {
return function() {
input.value += theNumberToAppend;
};
})(i);
}
DEMO #3