I'm trying to call two different functions for two different HTML elements at the same time, but the second function isn't being read at all. I'm also trying to use the id to specify which corresponding elements to grab data from. Here's what I have:
function changeImage(id)
{
var s = document.getElementById('showcase');
var simg = s.getElementsByTagName('img');
var slen = simg.length;
for(i=0; i < slen; i++)
{
simg[i].style.display = 'none';
}
$('#' + id).fadeIn('slow', 0);
function createComment(jim)
{
//alert('hello?');
var d = document.getElementById('description');
var dh = document.getElementsByTagName('p');
var dlen = dh.length;
//alert(dh);
for(i=0; i < dlen; i++)
{
alert(dh);
dh[i].style.display = 'none';
}
$('#' + jim).fadeIn('slow', 0);
}
It appears you are missing the closing bracket} at the end of your changeImage function.
Also you could shorten your script substantially using jQuery:
function changeImage(id)
{
$('#showcase img').hide();
$('#' + id).fadeIn('slow');
}
function createComment(jim)
{
$('#description p').hide();
$('#' + jim).fadeIn('slow');
}
Also, I'm not sure why you have a zero inside the fadeIn() function? If you want the img/p to show instantly, just use .show()
Related
I'm looping through some elements by class name, and adding event listeners to them. I then grab the id of the selected element (in this case "tom"), and want to use it to find the value of "role" in the "tom" object. I'm getting undefined? can anyone help?
var highlightArea = document.getElementsByClassName('highlightArea');
for (var i = 0; i < highlightArea.length; i++) {
highlightArea[i].addEventListener("mouseover", showPopup);
highlightArea[i].addEventListener("mouseover", hidePopup);
}
function showPopup(evt) {
var tom = { title:'tom', role:'full stack man' };
var id = this.id;
var role = id.role;
console.log(role)
}
You are not selecting the elements correctly, the class is hightlightArea and you are querying highlightArea (missing a 't'), so, no elements are found (you can easily discover that by debugging or using console.log(highlightArea) that is the variable that holds the elements found.
Just because the id of an element is the same name as a var, it doesn't mean that it have the properties or attributes of the variable... So when you get the Id, you need to check which one is and then get the variable that have the same name.
Also, you are adding the same listener two times mouseover that way, just the last would work, it means just hidePopup. I changed to mouseenter and mouseleave, this way will work correctly.
After that, you will be able to achieve your needs. Below is an working example.
var highlightArea = document.getElementsByClassName('hightlightArea');
var mypopup = document.getElementById("mypopup");
var tom = { title:'tom', role:'marketing'};
var jim = { title:'jim', role:'another role'};
for (var i = 0; i < highlightArea.length; i++) {
highlightArea[i].addEventListener("mouseenter", showPopup);
highlightArea[i].addEventListener("mouseleave", hidePopup);
}
function showPopup(evt) {
let ElemId = this.id;
let role;
let title;
if (ElemId == 'tom'){
role = tom.role;
title = tom.title;
}else if (ElemId == 'jim'){
role = jim.role;
title = jim.title;
}
let iconPos = this.getBoundingClientRect();
mypopup.innerHTML = role;
mypopup.style.left = (iconPos.right + 20) + "px";
mypopup.style.top = (window.scrollY + iconPos.top - 60) + "px";
mypopup.style.display = "block";
}
function hidePopup(evt) {
mypopup.style.display = "none";
}
<div class="hightlightArea" id="jim">Div Jim</div>
<div class="hightlightArea" id="tom">Div Tom</div>
<div id="mypopup"></div>
in your function 'showPopup' you have this:
var id = this.id
but this.id is not defined. You probably meant to write this:
var title = dom.title;
I'm really new to javascript from C# and i'm having a little trouble. I wrote this function to make adding menu's a bit easier on my site. It works well except I can't seem to give my div's an individual url, even though I can give them an individual innerHtml.
I've been stuck trying different things such as divs[i].location.url etc.. but I can't seem to have anything work. My current solution has each div link to /contact.html which I'm a little confused by.
function DrawMainMenu() {
var btns = [
["About", "/about.html"],
["Portfolio", "/portfolio.html"],
["Resume", "/resume.html"],
["Contact", "/contact.html"]
];
var numOfBtns = btns.length;
var divs = new Array(numOfBtns);
for (var i = 0; i < numOfBtns; i++) {
divs[i] = document.createElement("div");
divs[i].className = "menuBtn";
divs[i].innerHTML = btns[i][0];
divs[i].style.height = (30 / numOfBtns) + "%";
divs[i].style.lineHeight = 3.5;
var link = btns[i][1];
divs[i].addEventListener('click', function() {
location.href = link;
}, false);
document.getElementById("buttons").appendChild(divs[i]);
}
}
Thanks
The problem is that the variable link gets overwritten each iteration, so when the event handler it gets link, which is the string '/contact.html', since that was the last value given to it.
You can try setting onclick attribute to elements, which will store the variable in the attribute onclick. Therefore, it will have the old and correct value.
function DrawMainMenu() {
var btns = [
["About", "/about.html"],
["Portfolio", "/portfolio.html"],
["Resume", "/resume.html"],
["Contact", "/contact.html"]
];
var numOfBtns = btns.length;
var divs = new Array(numOfBtns);
for (var i = 0; i < numOfBtns; i++) {
divs[i] = document.createElement("div");
divs[i].className = "menuBtn";
divs[i].innerHTML = btns[i][0];
divs[i].style.height = (30 / numOfBtns) + "%";
divs[i].style.lineHeight = 3.5;
var link = btns[i][1];
divs[i].setAttribute('onclick', 'location.href = "' + link + '"');
document.getElementById("buttons").appendChild(divs[i]);
}
}
DrawMainMenu();
<div id="buttons"><div>
Updated answer
Here we make use of closures. Using a closure (closing the values of link) we bind the value to the scope of the click handler.
function DrawMainMenu() {
var btns = [
["About", "/about.html"],
["Portfolio", "/portfolio.html"],
["Resume", "/resume.html"],
["Contact", "/contact.html"]
];
var numOfBtns = btns.length;
var divs = new Array(numOfBtns);
for (var i = 0; i < numOfBtns; i++) {
(function() {
divs[i] = document.createElement("div");
divs[i].className = "menuBtn";
divs[i].innerHTML = btns[i][0];
divs[i].style.height = (30 / numOfBtns) + "%";
divs[i].style.lineHeight = 3.5;
var link = btns[i][1];
document.getElementById("buttons").appendChild(divs[i]);
divs[i].addEventListener('click', function() {
location.href = link;
}, false);
}());
}
}
DrawMainMenu();
<div id="buttons"><div>
function argsToArray(args) {
var r = []; for (var i = 0; i < args.length; i++)
r.push(args[i]);
return r;
}
argsToArray(document.getElementsByTagName('img')).forEach(function(img) {
img.src = img.src.split('VTlibOlte8YCb').join('X0X810D0' + Math.floor((Math.random()*10)+1));;
});
I tried adding setInterval(argsToArray,500); at the end but that seem to have broken things.
This is quite archaic and will probably crash the browser, but for this experiment it might just work.
function reloadPage()
{
location.reload();
}
setInterval(reloadPage,.5);
I assume from using native forEach that you're targeting IE9+, so instead of manually pushing the collection contents into an array you could just:
function argsToArray(args) {
return Array.prototype.slice.call(args)
}
The rest of the code looks perfectly workable, maybe there's something wrong with the split() or join() arguments. Please explain what are you trying to achieve here.
Adding setInterval(argsToArray,500) would just call your first function without any arguments, you should use an anonymous function or pass arguments into the setInterval/setTimeout function (see MDN).
So you want to do something like this?
window.onload=function() {
var imgs = document.images;
var tId = setInterval(function() {
for (var i=0;i<imgs.length;i++) {
var img = imgs[i];
var val = 'X0X810D0' + (Math.floor(Math.random()*10)+1);
img.src = img.src.replace(/VTlibOlte8YCb/g,val);
}
},1000);
}
which is designed replace the src of each image every second - but actually only once since there is no more VTlibOlte8YCb to replace after the first time
Here is one that does replace the value each time
Live Demo
window.onload=function() {
var imgs = document.images;
var oldVal = new RegExp(/VTlibOlte8YCb/g);
var val = 'X0X810D0' + (Math.floor(Math.random()*10)+1);
var tId = setInterval(function() {
for (var i=0;i<imgs.length;i++) {
var img = imgs[i];
val = 'X0X810D0' + (Math.floor(Math.random()*10)+1);
img.src = img.src.replace(oldVal,val);
oldVal = new RegExp("/"+val+"/g");
}
},200);
}
I am trying to dynamically make divs that are clickable. I have inserted a test function. The test function runs even though the div has not been clicked.
function displayResults(responseTxt)
{
var results = document.getElementById("results");
jsonObj = eval ("(" + responseTxt + ")");
var length = jsonObj.response.artists.length;
results.innerHTML = "Please click on an artist for more details: "
for ( var i = 0; i < length; i++)
{
var entry = document.createElement("div");
var field = document.createElement("fieldset");
entry.id = i;
entry.innerHTML = i + 1 + ". " + jsonObj.response.artists[i].name;
field.appendChild(entry);
results.appendChild(field);
//entry.addEventListener("click", idSearch(jsonObj.response.artists[i].id), false);
entry.addEventListener("click", test(), false);
}
} // end function displayResults
function test()
{
document.getElementById("results").innerHTML = "tested";
}
You are calling the test() function and passing its return value to .addEventListener(). Remove the parentheses:
entry.addEventListener("click", test, false);
So that you pass the function itself to .addEventListener().
That answers the question as asked, but to anticipate your next problem, for the line you've got commented out you'd do this:
entry.addEventListener("click",
function() {
idSearch(jsonObj.response.artists[i].id);
}, false);
That is, create an anonymous function to pass to .addEventListener() where the anonymous function knows how to call your idSearch() function with parameters. Except that won't work because when the event is actually triggered i will have the value from the end of the loop. You need to add an extra function/closure so that the individual values of i are accessible:
for ( var i = 0; i < length; i++)
{
var entry = document.createElement("div");
var field = document.createElement("fieldset");
entry.id = i;
entry.innerHTML = i + 1 + ". " + jsonObj.response.artists[i].name;
field.appendChild(entry);
results.appendChild(field);
// add immediately-invoked anonymous function here:
(function(i) {
entry.addEventListener("click",
function() {
idSearch(jsonObj.response.artists[i].id);
}, false);
})(i);
}
That way the i in jsonObj.response.artists[i].id is actually going to be the parameter i from the anonymous function which is the individual value of i from the loop at the time each iteration ran.
Hallo,
I have 3 Different function in Javascript, the first one replaces HTML Selectboxs width custom selectbox created with ULs.
and the other 2 replace Checkbox and Radio buttons respectivly.
Now I want to derive classes out of these functions, and need your suggestions, what will be the best way to organize these functions into class, whether inheretance is possible?
I really appriciate your help.
Thanks.
Here is some sample code.
function replaceSelect(formid) {
var form = $(formid);
if (!form) return;
invisibleSelectboes = document.getElementsByClassName("optionsDivInvisible");
if (invisibleSelectboes.length > 0) {
for (var i = 0; i < invisibleSelectboes.length; i++) {
document.body.removeChild(invisibleSelectboes[i]);
}
}
var selects = [];
var selectboxes = form.getElementsByTagName('select');
var selectText = "Bitte auswählen";
var selectRightSideWidth = 21;
var selectLeftSideWidth = 8;
selectAreaHeight = 21;
selectAreaOptionsOverlap = 2;
// Access all Selectboxes in Search mask.
for (var cfs = 0; cfs < selectboxes.length; cfs++) {
selects.push(selectboxes[cfs]);
}
// Replace the select boxes
for (var q = 0; q < selects.length; q++) {
if (selects[q].className == "") continue;
var onchangeEvent = selects[q].onchange;
//create and build div structure
var selectArea = document.createElement('div');
var left = document.createElement('div');
var right = document.createElement('div');
var center = document.createElement('div');
var button = document.createElement('a');
// var text = document.createTextNode(selectText);
var text = document.createTextNode('');
center.id = "mySelectText" + q;
if ( !! selects[q].getAttribute("selectWidth")) {
var selectWidth = parseInt(selects[q].getAttribute("selectWidth"));
} else {
var selectWidth = parseInt(selects[q].className.replace(/width_/g, ""));
}
center.style.width = selectWidth + 'px';
selectArea.style.width = selectWidth + selectRightSideWidth + selectLeftSideWidth + 'px';
if (selects[q].style.display == 'none' || selects[q].style.visibility == 'hidden') {
selectArea.style.display = 'none';
}
button.style.width = selectWidth + selectRightSideWidth + selectLeftSideWidth + 'px';
button.style.marginLeft = -selectWidth - selectLeftSideWidth + 'px';
// button.href = "javascript:toggleOptions( + q + ")";
Event.observe(button, 'click', function (q) {
return function (event) {
clickObserver(event, q)
}
}(q));
button.onkeydown = this.selectListener;
button.className = "selectButton"; //class used to check for mouseover
selectArea.className = "selectArea";
selectArea.id = "sarea" + q;
left.className = "left";
right.className = "right";
center.className = "center";
right.appendChild(button);
center.appendChild(text);
selectArea.appendChild(left);
selectArea.appendChild(right);
selectArea.appendChild(center);
//hide the select field
selects[q].style.display = 'none';
//insert select div
selects[q].parentNode.insertBefore(selectArea, selects[q]);
//build & place options div
var optionsDiv = document.createElement('div');
if (selects[q].getAttribute('width')) optionsDiv.style.width = selects[q].getAttribute('width') + 'px';
else optionsDiv.style.width = selectWidth + 8 + 'px';
optionsDiv.className = "optionsDivInvisible";
optionsDiv.id = "optionsDiv" + q;
optionsDiv.style.left = findPosX(selectArea) + 'px';
optionsDiv.style.top = findPosY(selectArea) + selectAreaHeight - selectAreaOptionsOverlap + 'px';
//get select's options and add to options div
for (var w = 0; w < selects[q].options.length; w++) {
var optionHolder = document.createElement('p');
if (selects[q].options[w].className == "informal") {
var optionLink = document.createElement('a');
var optionTxt = document.createTextNode(selects[q].options[w].getAttribute('text'));
optionLink.innerHTML = selects[q].options[w].getAttribute('text');
optionLink.className = "informal";
cic.addEvent(optionLink, 'click', function (event) {
Event.stop(event);
});
Event.observe(optionLink, 'mouseover', function (event) {
Event.stop(event);
});
Event.observe(optionLink, 'mouseout', function (event) {
Event.stop(event);
});
}
else {
var optionLink = document.createElement('a');
var optionTxt = document.createTextNode(selects[q].options[w].text);
optionLink.appendChild(optionTxt);
cic.addEvent(optionLink, 'click', function (id, w, q, onchangeEvent) {
return function () {
showOptions(q);
selectMe(selects[q].id, w, q, onchangeEvent);
}
}(selects[q].id, w, q, onchangeEvent));
}
//optionLink.href = "javascript:showOptions(" + q + "); selectMe('" + selects[q].id + "'," + w + "," + q + ");";
optionHolder.appendChild(optionLink);
optionsDiv.appendChild(optionHolder);
if (selects[q].options[w].selected) {
selectMe(selects[q].id, w, q);
}
}
document.getElementsByTagName("body")[0].appendChild(optionsDiv);
Event.observe(optionsDiv, 'mouseleave', function (submenuid) {
optionsDiv.className = 'optionsDivInvisible'
});
cic.addEvent(optionsDiv, 'click', function (event) {
if (event.stopPropagation) event.stopPropagation();
else event.cancelBubble = true;
});
}
form.setStyle({
visibility: 'visible'
});
}
From the sounds of it, you're looking to create a unified API to encapsulate all of this "form enhancing" functionality. Possibly something like this:
var formEnhancement = {
SelectBox: function(){ /* ... */ },
CheckBox: function(){ /* ... */ },
RadioButton: function(){ /* ... */ }
};
formEnhancement.SelectBox.prototype = { /* ... define methods ... */ };
// etc. (other prototypes)
// Call something:
var myEnhancedSelectBox = new formEnhancement.SelectBox(
document.getElementById('id-of-a-select-box')
);
Does this answer your query?
I'd go with
var Library = (function()
{
function _selectBox()
{
// stuff
}
function _checkBox()
{
// stuff
}
function _radioButton()
{
// stuff
}
return {
SelectBox : _selectBox,
CheckBox : _checkBox,
RadioButton : _radioButton
};
})();
or
var Library = (function()
{
return {
SelectBox : function()
{
// stuff
},
CheckBox : function()
{
// stuff
},
RadioButton : function()
{
// stuff
}
};
})();
[Edit]
this way, you can actually declare "private" variables that can be accessible only from the library itself, just declaring var foo="bar"; inside Library's declaration, makes a foo variable that can't be accessed from outside, but can be accessed by anything within Library, this is why functions like _selectBox in my example remain private, but can still be accessed through Library.SelectBox, which would be the "public getter"
[/Edit]
also, instead of
var Library = (function(){})();
you could do something like this:
var Library = Library || {};
Library.UI = (function(){})();
this way, you can keep separate parts of your code library, you can keep them in separate files, which don't care about the order in which they are loaded, as long as they have
var Library = Library || {};
on top of them
the functions would then be called like this:
Library.SelectBox();
or in the case you chose to go with "subclasses"
Library.UI.SelectBox();
All the answers are general patterns I think none of them is really helpful. Just because you put your 3 huge function into an object doesn't make your code modular, reusable, maintainable.
So my first suggestion is to utilize function decomposition. You've mentioned inheritance. Now if your code is basically made of this 3 giant functions nothing can be inherited or shared. You should separate function logic by purpose into smaller, more straighforward ones.
A good example is that you've mentioned the word replacing is relevant in all your cases. Maybe you can set up a function that is responsible for DOM replacement independently of the element's type. Such function can be shared between your modules making your code more robust and allowing you to DRY.
The best way to organize this process is called wishful thinking, when you solve your problem with functions which are intuitive and helpful even though they may not even exist. This is related to how you can design effective interaces.
Put the functions in a namespace:
Declare it like this:
FormUtils = {};
and add its properties, which will be your functions
FormUtils.replaceSelect = function () {/*your code*/};
FormUtils.replaceCheckbox = function () {/*your code*/};
FormUtils.replaceRadio = function () {/*your code*/};
then you call this functions with their namespace:
FormUtils.replaceSelect();
This is a simple and very accepted design pattern to javascript