I am trying to use <label> elements in my html contact form like the HTML5 placeholder attribute for inputs. I have written the following JavaScript to to act as a reusable function witch will provide the following functionality.
Find the input by name.
Get the value of the input.
Find the label belonging to the input.
Change the label style depending on the state of the input.
Change the label style depending on the value of the input.
However it is not working and I don't know why as no errors appear in the console. What am I doing wrong? here is a JS Fiddle with code
function placeholder(field_name) {
// Get the input box with field_name
// Then get input value
var box = document.getElementsByName(field_name);
var i;
for (i = 0; i < box.length; i++) {
var value = document.getElementById(box[i].value);
}
// Get the labels belonging to each box using the HTML for attribute
var labels = document.getElementsByTagName('LABEL');
for (i = 0; i < labels.length; i++) {
if (labels[i].htmlFor !== '') {
var elem = document.getElementById(labels[i].htmlFor);
if (elem) {
box.label = labels[i];
}
}
}
// Colors
var focusColor = "#D5D5D5";
var blurColor = "#B3B3B3";
// If no text is in the box then show the label grey color
box.onblur = function () {
box.label.style.color = blurColor;
};
// If input focuses change label color to light grey
box.onfocus = function () {
box.label.style.color = focusColor;
};
// If there is text in the box then hide the label
if (box.value !== "") {
// Quick do something, hide!
box.label.style.color = "transparent";
}
}
// Call the function passing field names as parameters
placeholder(document.getElementsByName("email"));
placeholder(document.getElementsByName("firstName"));
placeholder(document.getElementsByName("lastName"));
This might be considered a little overkill on the number of listeners I've used, feel free to remove any you think unnecessary, but I've tried to employ your HTML structure as you have it and give you all desired effects. It should work for either the <label>s for matching the <input>s id OR matching it's <name> (given no id matches). I'll always say prefer using an id over name. I believe this JavaScript should also work in all browsers too, except the addEventListener for which you'd need a shim for old IE versions (let me know if it doesn't in one/the error message).
Demo
var focusColor = "#D5D5D5", blurColor = "#B3B3B3";
function placeholder(fieldName) {
var named = document.getElementsByName(fieldName), i;
for (i = 0; i < named.length; ++i) { // loop over all elements with this name
(function (n) { // catch in scope
var labels = [], tmp, j, fn, focus, blur;
if ('labels' in n && n.labels.length > 0) labels = n.labels; // if labels provided by browser use it
else { // get labels from form, filter to ones we want
tmp = n.form.getElementsByTagName('label');
for (j = 0;j < tmp.length; ++j) {
if (tmp[j].htmlFor === fieldName) {
labels.push(tmp[j]);
}
}
}
for (j = 0; j < labels.length; ++j) { // loop over each label
(function (label) { // catch label in scope
fn = function () {
if (this.value === '') {
label.style.visibility = 'visible';
} else {
label.style.visibility = 'hidden';
}
};
focus = function () {
label.style.color = focusColor;
};
blur = function () {
label.style.color = blurColor;
};
}(labels[j]));
n.addEventListener('click', fn); // add to relevant listeners
n.addEventListener('keydown', fn);
n.addEventListener('keypress', fn);
n.addEventListener('keyup', fn);
n.addEventListener('focus', fn);
n.addEventListener('focus', focus);
n.addEventListener('blur', fn);
n.addEventListener('blur', blur);
}
}(named[i]));
}
};
placeholder("email"); // just pass the name attribute
placeholder("firstName");
placeholder("lastName");
http://jsfiddle.net/cCxjk/5/
var inputs = document.getElementsByTagName('input');
var old_ele = '';
var old_label ='';
function hide_label(ele){
var id_of_input = ele.target.id;
var label = document.getElementById(id_of_input + '-placeholder');
if(ele.target == document.activeElement){
label.style.display = 'none';
}
if (old_ele.value == '' && old_ele != document.activeElement){
old_label.style.display = 'inline';
}
old_ele = ele.target;
old_label = label;
}
for(var i = 0; i < inputs.length; i++){
inputs[i].addEventListener('click', hide_label);
}
I will point out a couple things, you will have to find away around the fact that the label is inside the input so users now can't click on half of the input and actually have the input gain focus.
Also I guess you want to do this in IE (otherwise I would strongly advise using the html5 placeholder!) which means you would need to change the ele.target to ele.srcElement.
Related
as you can see here https://jsfiddle.net/kztnmm9o/ I am trying to check if the inputs are empty. If they are empty I want to display the div id="fehler", if every input has a value (must be a number, if not it shall display id="fehler" as well) I want to do the function. I am pretty new to javascript, might be a obvious mistake.
Thank you for your help!
This is the orignal javascript code without checking the inputs, which works:
var selectors = document.querySelectorAll("#eing1, #eing2, #eing3");
for (var i = 0; i < selectors.length; i++) {
selectors[i].addEventListener('keyup', function(event) {
event.preventDefault();
if (event.keyCode == 13) {
document.getElementById("button").click();
}
});
}
function ausgeben(){
var kostentisch = parseInt(document.getElementById("eing1").value)
var bruttogehalt = parseInt(document.getElementById("eing2").value)
var arbeitstage = parseInt(document.getElementById("eing3").value)
var stundenlohn = bruttogehalt/arbeitstage/8;
var arbeitszeit = arbeitstage*8;
var produktivitaetssteigerung = arbeitszeit*0.12;
var produktivitaetssteigerung2 = arbeitstage/produktivitaetssteigerung;
var gewinnprotag = produktivitaetssteigerung2*stundenlohn;
var amortisationszeit = Math.round(kostentisch/ gewinnprotag);
document.getElementById("arbeitszeit").innerHTML=arbeitszeit + " Stunden";
document.getElementById("produktivitaetssteigerung").innerHTML=produktivitaetssteigerung + " Stunden";
document.getElementById("amortisationszeit").innerHTML=amortisationszeit + " Tage";
}
updated fiddle: https://jsfiddle.net/kztnmm9o/3/
Changed the testing to this:
var test = document.querySelectorAll('input[type="text"]');
var error = false;
for (var i = 0; i < test.length; ++i) {
if (test[i].value == "")
{
test[i].style.borderColor = "red";
error = true;
}
}
I also made some minor changes following this logic, but it should be pretty simple to understand.
I also added this.style.borderColor = "transparent"; to keyup event but I'm not sure whether you like or not. So change on will.
Is there a way to use the qualtrics javascript api (or, if not, a workaround) to programatically clear all entries made to radio buttons on a page?
My usage case is in a matrix table question that "pipes" (actually uses embedded data) values from the previous question to puts calculated numbers into the statements. However, if the respondent navigates back then when the return to the following question the numbers have changed but the responses have remained. As such, if it is the second time a respondent is viewing a page constructed like this, I want to clear all their previous answers.
I want to make sure that qualtrics' data is updated properly.
My survey is currently using the JFE engine if that makes a difference.
Qualtrics.SurveyEngine.addOnload(function() {
var QID = this.questionId;
var that = this;
var counts = [];
var radioButtonsClean = [];
var radioButtons = $(QID).getElementsByTagName('input');
var radioIndex = [];
for(var i=0; i<radioButtons.length; i++) {
if(radioButtons[i].type == 'radio') {
radioButtonsClean.push(radioButtons[i]);
radioIndex.push(radioButtons[i].id);
}
}
// Set counts for each displayed radio button to 0
for(var i=0; i<radioButtonsClean.length; i++) {
counts[i] = 0;
}
this.questionclick = function(event,element){
if (element.type == 'radio') {
var thisId = element.id;
var spotCheck = radioIndex.indexOf(thisId);
var count = counts[spotCheck];
if (count == 0) {
for(var i=0; i<counts.length; i++) {
counts[i] = 0;
}
counts[spotCheck] = 1;
}
else {
this.setChoiceValue(element.id.split('~')[2], element.id.split('~')[3], false);
counts[spotCheck] = 0;
}
}
}
});
I want to fill my Selection by Script. I am struggling with the filling method.
When I want to fill my FontSizeMenu I use this code:
function FillFontSizeMenu() { // run this at Start
FillSelection(GetPossibleFontSizes(), "fontSizeMenu"); // Fill the selection with values
}
function GetPossibleFontSizes(){ // Return all values for the menu
var sizeMin = 1;
var sizeMax = 100;
var possibleSizes = [];
for(var i = sizeMin; i <= sizeMax; i++)
{
possibleSizes.push(i);
}
return possibleSizes;
}
function FillSelection(possibleValues, elementId){ // Fill the menu
for(var i = 0; i < possibleValues.length; i++)
{
var optionElement = "<option></option>"; // add one option element per value
optionElement.html(possibleValues[i]);
optionElement.val(possibleValues[i]);
$(elementId).append(optionElement); // add the option element to the selection
}
}
Something is wrong with the "FillSelection" method, it says the option element is not a function.
Does someone knows what is wrong or missing?
Thanks
Wrap html string in jQuery()
var optionElement = $("<option></option>");
You can also use jQuery() to set html, value and call .appendTo()
$("<option></option>", {
html: possibleValues[i],
value: possibleValues[i],
appendTo: $(elementId)
});
Here is one more solution
You need to create new Option object
$(elementId).append(new Option("Font size "+i, possibleValues[i]));
and you should pass #id to function:
FillSelection(GetPossibleFontSizes(), "#fontSizeMenu")
function FillFontSizeMenu() { // run this at Start
FillSelection(GetPossibleFontSizes(), "#fontSizeMenu"); // Fill the selection with values
}
function GetPossibleFontSizes(){ // Return all values for the menu
var sizeMin = 1;
var sizeMax = 100;
var possibleSizes = [];
for(var i = sizeMin; i <= sizeMax; i++)
{
possibleSizes.push(i);
}
return possibleSizes;
}
function FillSelection(possibleValues, elementId){ // Fill the menu
for(var i = 0; i < possibleValues.length; i++)
{
$(elementId).append(new Option("Font size "+i, possibleValues[i])); // add the option element to the selection
}
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button onclick="FillFontSizeMenu()">Populate it</button>
<select id="fontSizeMenu">
</select>
You have to create an element first then append properties using jquery. Something like this
var ele = document.createElement("<option>");
$("body").append(ele);
$(ele).html(possibleValues[i]);
$(ele).val(possibleValues[i]);
I'm building an interface that consists of 9 cells in table. When a person mouses over a cell, I want other cells to become visible, and change the text content of some of the cells. I can do that just fine if I create individual functions to change the content of each cell, but that's crazy.
I want a single function to change the text depending on the cells involved. I created a function that can take n arguments, and loops through making changes based on the arguments passed in to the function. It doesn't work.
Code for the function is below. If I call it, onMouseOver="changebox('div3')", the argument makes it to the function when I mouse over the cell. If I uncomment the document.write(cell) statement, in this instance, it prints div3 to the screen. So... why isn't it making any changes to the content of the div3 cell?
function changebox() {
for (var i = 0; i < arguments.length; i++) {
var cell = document.getElementById(arguments[i]).id;
var text = "";
if (cell == 'div3') {
text = "Reduced Travel";
} else if (cell == 'div4') {
text = "Reduced Cost";
}
//document.write(cell)
cell.innerHTML = text;
}
}
In your code cell is a string which holds the id of the object. Update the code as follows
function changebox() {
for (var i = 0; i < arguments.length; i++) {
var cell = document.getElementById(arguments[i]),
text = "";
if (cell.id == 'div3') {
text = "Reduced Travel";
} else if (cell.id == 'div4') {
text = "Reduced Cost";
}
//document.write(cell)
cell.innerHTML = text;
}
}
UPDATE :
You can reduce the code as #Tushar suggested.
No need of iterating over arguments(assuming there are only two elements, but can be modified for more elements).
function changebox() {
// As arguments is not real array, need to use call
// Check if div is present in the arguments array
var div3Index = [].indexOf.call(arguments, 'div3') > -1,
div4Index = [].indexOf.call(arguments, 'div4') > -1;
// If present then update the innerHTML of it accordingly
if (div3Index) {
document.getElementById('div3').innerHTML = 'Reduced Travel';
} else if (div4Index) {
document.getElementById('div4').innerHTML = 'Reduced Cost';
}
}
function changebox() {
var args = [].slice.call(arguments);
args.map(document.getElementById.bind(document)).forEach(setElement);
}
function setElement(ele) {
if (ele.id === 'div3') {
ele.innerHTML = "Reduced Travel";
} else if (ele.id === 'div4') {
ele.innerHTML = "Reduced Cost";
}
}
this make your function easy to be tested
As your assigning the cell variable the id of the element and changing the innerHTML of cell which is not valid .
var changeText = function() {
console.log("in change text");
for(var i= 0; i<arguments.length; i++) {
var elem = document.getElementById(arguments[i]);
var cell = document.getElementById(arguments[i]).id;
var text = "";
console.log(cell)
if (cell === "div-1") {
text = cell+" was selected!!";
} else if(cell === "div-3") {
text = cell+" was selected!!";
} else {
text = cell+" was selected";
}
elem.innerHTML = text;
}
}
This would properly change the text of div mouseovered!!
I am trying to get the value from a checkbox using javascript.
I want only one checkbox value to be passed to the javascript function, and if multiple are selected, an alert box informing that only one box can be checked for the function.
I've tried this:
var publish_trigger = document.querySelector("#publish_trigger");
publish_trigger.onclick = function() {
var _posts = document.getElementsByName('post_id[]');
var check = _posts.checked;
var boxes = _posts.length;
var txt = "";
if(check.length > 1) {
alert("Only one at a time");
} else {
for (i = 0; i < boxes; i++) {
if (_posts[i].checked) {
txt = txt + _posts[i].value + " "
}
}
}
alert(txt);
return false;
}
This code is wrong:
var _posts = document.getElementsByName('post_id[]');
var check = _posts.checked;
getElementsByName() returns a NodeList (effectively an array) of elements, so your variable _posts doesn't have a checked property. You need to loop through _posts to count the checked property on the individual elements within _posts.
You already have a for loop so add the validation in there:
var count = 0;
for (var i = 0; i < boxes; i++) {
if (_posts[i].checked) {
if (++count > 1) {
alert("Only one checkbox may be checked at a time.");
return false;
}
// I don't know what you're trying to do with the following line
// but I've left it in.
txt = txt + _posts[i].value + " "
}
}
(Note: unrelated to your question, you should declare the loop counter i within your function otherwise it will be global and might lead to hard to debug problems if you are using it in other places too.)