I am dynamically creating an unordered list and adding items to it on a click of a button. I append this to a section that has contenteditable attribute set true. However, I do not see it working. I did set the contenteditable attribute to true even for the list but I guess it is supposed to inherit that from the section it is appended to. Here is the code of what I am doing.
// create text input
var categoryInput = document.createElement('input')
// create button to add the text entered to a list
var btnAddToList = document.createElement('input');
btnAddToList.type ="button";
//create a section to add a list to
var section = document.createElement('section');
var ul=document.createElement('ul');
section.appendChild(ul);
section.contenteditable = "true";
ul.contenteditable = "true";
//create an event handler to add to the list
if (btnAddToList.addEventListener) { btnAddToList.addEventListener('click', function () { addToList(ul, categoryInput.value);});
} else if (btnAddToList.attachEvent) {
btnAddToList.addEvent('click', function () { addToList(ul, categoryInput.value);});
Here is the function I call
function addToList(unorderedlist, inputText) {
if(inputText.length == 0) {
alert("Add Text");
return;
}
var listitem = document.createElement('li');
var listvalue = document.createTextNode(inputText);
listitem.appendChild(listvalue);
unorderedlist.appendChild(listitem);
}
What am I doing wrong or not doing? Any help appreciated. Thanks
The property is contentEditable (note upper-case 'E'), not contenteditable.
section.contentEditable = "true";
You need to set the attribute, not the property:
section.setAttribute('contenteditable', 'true');
Instead of
section.contenteditable = "true";
Some more info here and here (in the context of jQuery, but covers the topic splendidly nonetheless).
My current understanding of the difference is that attributes are the things you can set through markup (id, class, contenteditable, etc.), whereas properties are the properties of the actual javascript objects representing the DOM nodes. As the linked article mentions, the two are often kept in sync by the browser, but not always.
Edit:
As Tim Down states in his answer, while the above works (setting the attribute), the actual problem is that the name of the property is cased wrong. It should be
section.contentEditable = "true"; //Note the upper case 'E'
The reason setting the attribute works, is that attributes are case-insensitive.
Related
I am trying to Get First Child with classname Plain Javascript.
I am trying to write my own form validation and trying the error message i appended and remove it. As well as dont append if error message is already there.
If you help me with just the first part getting child with class name that whould be great.
function display_error(selector, message) {
selector.insertAdjacentHTML('afterend', "<h1 class='js-error' >" + message + "</h1>");
}
function validateForm() {
// Validate Name Field
// Check if name has les than 3
var elem = document.getElementById("name")
if (elem.value.length < 3) {
display_error(elem, "Less than 3")
return false;
} else {
// here is the error
error_label = elem.querySelector('.js-error');
error_label.textContent = "more than 3"
}
}
here is a fiddle
https://jsfiddle.net/efh941cc/3/
The beautiful thing about document.querySelector() is that you can use CSS selectors rather than the, often clunky, DOM API.
CSS provides a very simple selector called first-child which does exactly what you need.
// Find the first element that uses the .test class that is a child of another element.
var firstTest = document.querySelector(".test:first-child");
// Now that you've scanned and found the element and stored a reference to it
// in a variable, you can access any aspect of the element.
console.log(firstTest.textContent);
firstTest.innerHTML = "<span>Now, I have completely different content than before!</span>";
// Now, we can get a reference to other elements that are relative to the last
// one we found.
var firstTestError = document.querySelector(".test:first-child + .error");
firstTestError.style.backgroundColor = "aqua";
firstTestError.innerHTML = "<span>Required</span>";
<div>
<span class="test">one</span><span class="error"></span>
<div class="test">two</div>
<div class="test">three</div>
</div>
In modern JavaScript, to get the first child with a class name, you can use the following:
document.querySelector('element.class:first-child')
Here, you supply the actual element, and the actual class name.
document.querySelector is available in all modern browsers, and will take any string which matches a CSS selector. It even works in IE8, though the :first-child pseudo class is not available there.
const GetFirstChild = document.querySelector(' .PlainJavascript');
I am a noob, I was developing a chrome plugin , which gives the info about the elements clicked on in the web page,
It works fine , but the problem is the e.target works only on links and input boxes, but when I click on some text it does not do anything , it is blank[Expected: the id/class/etc of the div within which the text is present]
Here is my code (please do not mark me down, as am really new to this):
document.addEventListener("click", function (e) {
var dom_id = e.target.getAttribute("id");
var dom_name = e.target.name.toString();
var dom_class = e.target.className.toString();
var dom_html = e.target.innerHTML;
var dom_href = e.target.getAttribute("href");
var dom_text = e.target.text;
var dom_el = e.target.tagName;
var dom_src = e.target.src;
}, false);
All I want is when I click on a div, I should get the div info, span should give span info, likewise etc.
The problem
Since (based on another question of yours) it seems the listener is registered properly (e.g. after the DOM has been loaded, the only problem I see, is that you are calling e.target.name.toString();.
The explanation
It will only work with elements that have the name attribute set (not only for links or inputs, but any element that has a name attribute). For elements with no name, an exception will be raised, as you are calling method toString of undefined (e.target.name equals undefined when the name attribute is missing).
(Note that this is not the case with className, because className refers to the elements property (not directly the class attibute and it defaults to an empty string when the class attribute is missing.)
The solution
Just remove the .toString() part and it will work:
var dom_name = e.target.name;
Based on how you use that var later on, you might want to add a check and set it to an empty string if it not defined:
var dom_name = (e.target.name !== undefined) ? e.target.name : '';
I have this simple function:
var x = document.createTextNode("ERROR");
document.body.appendChild(x);
So then I need to create an IF to verify if this message exist [If this message has been created]. This is the problem, I don't know how to do that.
GetElementByID seems to don't work with element created by dynamically.
Any help? Thanks.
You can use document.contains to check if a element is in the DOM
Just a quick example of how it works
document.contains($('<div>')[0]); // FALSE
And
document.contains($('<div>').appendTo('body')[0]); // TRUE
jQuery only used for a shorthand to element creation
This also works for text nodes and you can use contains on any node.
document.body.contains(Node); // Example
The browser support is somewhat very good
Documentation: https://developer.mozilla.org/en-US/docs/Web/API/Node.contains
Question specifics:
var x = document.createTextNode("ERROR");
document.body.appendChild(x);
document.contains(x); // Should be TRUE
You are creating a text node, not an element. You need to create an element and give it an id to be able to use getElementById.
I don't know of any reasonable way to search for a text node, although you could always check the text nodes of the element you attached it to and see if it's there.
var message = "ERROR";
var t = document.createTextNode(message);
var node = document.getElementById('content').appendChild(t);
if (document.getElementById('content').innerHTML !== message) {
console.log('element not added');
} else {
console.log('element added');
}
Here is a fiddle:
http://jsfiddle.net/btipling/rBg4w/
I believe this would work:
var x = document.createTextNode("ERROR");
var element = document.body.appendChild(x); //returns text node
if(!element){
//element was not added
}
although if I were you I might create a span element with an id or a class called error. This way you can apply any css styles to it.
Try this:
var x = document.createTextNode("ERROR");
document.body.appendChild(x);
if (document.body.innerText.indexOf('ERROR')>=0){
alert('"ERROR" found');
}
indexOf doesn't work in all browsers.
As #slowpython said I'd rather create a DOM element with ID or NAME.
I'm successfully creating some dynamic input textboxes using the following javascript:
var type = "Textbox";
var foo = document.getElementById("fooBar");
for (i = 1; i <= totalQty; i = i + 1) {
var textbox = document.createElement("input");
//Assign different attributes to the element.
textbox.setAttribute("type", type + i);
//textbox.setAttribute("value", type + i);
textbox.setAttribute("name", type + i);
textbox.setAttribute("id", type + i);
textbox.setAttribute("style", "width:300px");
textbox.setAttribute("width", "300px");
//Append the element in page (in span).
var newline = document.createElement("br");
foo.appendChild(newline);
foo.appendChild(textbox);
}
Everything works fine with that. Once the user keys in data and clicks submit however, I need to go back and set the background-color of any textboxes with an error to red. I found some code to do the actual coloring:
textbox.style.backgroundColor = "#fa6767";
...and I know the exact name of the textbox with the error (i.e. "Textbox1", "Textbox2", "Textbox3", etc) but I'm not sure how to programatically assign this background color code to the specific textbox. I can't use something like this, since all code is dynamically generated:
errorTextbox = $("#Textbox1");
Any suggestions?
It looks like you're building a form validation script. Here's an easier way to do this:
1) Create an entry in your stlyesheet for your error class. Adding and removing a class requires fewer steps than assigning properties individually.
.error {
background-color: #ff0000;
}
2) Give all the textboxes you wish to validate a unique class name "valMe", for example.
3) Then loop through them during the validation step:
$('.valMe').each(function() {
$(this).removeClass('error');
if($(this).text=='') {
$(this).addClass('error');
}
})
By using "this" you refer to the current element, so you don't even need to know the ID of the element.
If you already know the name (in this case identical to the id) of the element, you can use jQuery to select the element by forming the selector using string concatenation. Assuming you have a variable that stores the name/id of the text box that has the error, then it's a relatively simple process:
var errorTextboxName = 'Textbox1';
$('#' + errorTextboxName).css('background-color', 'red');
I ended up going with the following:
document.getElementById('Textbox1'.style.backgroundColor = "#fa6767";
I originally didn't think I would be able to capture my "Textbox1" control in this fashion since when I viewed the html source code, there was no "Textbox1" due to the fact I dynamically created it.
Thanks.
I am creating tables with the appendchild method. They contain checkboxes. I would like to be able to have the user to click a checkbox and have it run a function. I need the function to access the other checkbox and see if its checked or not. Currently I can' seem to reference the table or checkboxes at all.
My code for creating the table is:
function makeTable() {
var ItemA = Item.ItemName.options[Item.ItemName.options.selectedIndex].text;
var myParagraph=document.getElementById("myLine");
myForm = document.createElement("FORM");
mytable = document.createElement("TABLE");
mytablebody = document.createElement("TBODY");
var CB_Format = document.createElement('input');
CB_Format.type = 'checkbox';
CB_Format.name= "CB_Test";
CB_Format.value= 1;
CB_Format.setAttribute("name", "CBTest2");
CB_Format.onclick = changeColor;
theCell.appendChild(CB_Format);
var CB_Delete = document.createElement('input');
CB_Delete.type = "checkbox";
CB_Delete.name = "CB_Test";
CB_Delete.setAttribute("name", "CBTest2");
CB_Delete.value = 2;
CB_Delete.onclick = answer;
theCell.appendChild(CB_Delete);
My understanding is that my solution should be as simple as alert(document.form.checkbox.checked) but no matter what combination of possible names I try I get the error that it is null or not an object in both ie8 and firefox.
Thank you for your help
> function makeTable() {
> var ItemA = Item.ItemName.options[Item.ItemName.options.selectedIndex].text;
> var myParagraph=document.getElementById("myLine");
> myForm = document.createElement("FORM");
> mytable = document.createElement("TABLE");
> mytablebody = document.createElement("TBODY");
If you don't declare variables with var, they become global variables when first evaluated. Always declare variables.
> var CB_Format = document.createElement('input');
> CB_Format.type = 'checkbox';
> CB_Format.name= "CB_Test";
> CB_Format.value= 1;
> CB_Format.setAttribute("name", "CBTest2");
The above line changes the name property from the value assigned a couple of lines earlier, why do both? Just assign the correct value to the name property once:
CB_Format.name = "CBTest2";
The same goes for the use of setAttribute later. Note that setting the value of a property doesn't always change the associated attribute in some browsers, so always use properties unless there is a specific reason to use setAttribute,
[...]
My understanding is that my solution should be as simple as
alert(document.form.checkbox.checked) but no matter what combination
of possible names I try I get the error that it is null or not an
object in both ie8 and firefox. Thank you for your help
Form controls are made available as named properties of the form element. If there is more than one control with the same name, they are in a collecion. Assigning different values to the name property and attribute is asking for trouble. It should be that the second assignment overwrites the first, but no doubt there is a browser somewhere that will keep both values (one for the attribute and the other for the property).
The simple solution is to always use properties and only assign one value. If you want the name to be CBTest2 (since that is the second one assigned), then when the input is added to the form and the form to the document it will be available as:
document.forms['formName'].elements['CBTest2']
If the names are valid identifiers, then shorthand dot notation can be used:
document.formName.CBTest2
Since you have two elements with that name, the returned value will be a collection (a little like an array), so to get the first one, use:
document.formName.CBTest2[0]
You could use some code similar to...
var checkboxes = document.querySelectorAll('#some-form input[type="checkbox"]');
Array.forEach(checkboxes, function(checkbox) {
checkbox.addEventListener(function() {
var hasOtherCheckedCheckbox = Array.every(checkboxes, function(checkbox) {
return checkbox.checked;
});
});
});
Of course, for complete browser support, you'll need to modify this code a bit.