I have looked around, but I'm not seeing anything that specifically addresses this. My goal is to have a link, which can be clicked to either add content or "undo" the act of adding that content. I am trying to us the following:
function ShowDiv() {
if (null == window.set) {
document.getElementById("box2").innerHTML = "Some Content";
window.set = "set";
} else
location.reload();
}
Link
<div id="box2"></div>
This allows me to click the link to show some content inside some div. And then to click the link again to remove that content.
However, I am wondering if there is a way to achieve this result, that also allows the user to click the browser's back button to return the page to the state it was in before triggering the function (e.g., to reload the page).
You are looking for the HTML5 history API. This allows you to push state onto the history as if the browser loaded a different location without actually sending a request and replacing all content and javascript state. This allows the back and forward buttons to work, as long as your JavaScript code shows the correct content according to the current URL.
Resources:
W3C
MDN
Dive Into HTML5
Related
I want to navigate inside the page with an animation using Javascript, but also change the URL so the user can click "back" to go back to the previous "page".
I have no idea how to approach this. Do I put the content I'm navigating to on a new html page, or on the same page?
What I've tried so far:
Some Other Page
This will completely reload to someOtherPage, and won't allow animations.
Some Other Page
<script>
function animateToOtherSection() {
//things like fade in/out or scroll
}
</script>
This works if the content I'm navigating to exists in this page, which is okay, but the URL won't be changed (except for the additional #).
If i try to change window.href in Javascript, the entire page reloads, which is not desired.
This question was inspired by some websites like this. When the See our projects button is clicked, although it as an anchor element, the page doesn't reload, but a fade out/in executes and the navigation bar above stays throughout. If I click the 'back' button in my browser, another animation takes me back to the splash screen.
Note: This is not an option:
Some Other Page
I don't want to just scroll to an element, but manipulate and show/hide a lot of elements on the screen.
Thanks in advance for the answers!
The DOM window object provides access to the browser's history through the history object. It exposes useful methods and properties that let you move back and forth through the user's history, as well as -- starting with HTML5 -- manipulate the contents of the history stack.
https://developer.mozilla.org/en-US/docs/Web/API/History_API
Load data from the server and place the returned HTML into the matched element.
http://api.jquery.com/load/
You can make it easy here is example:
HTML:
<button id="changeUrl">See our projects</button>
JavaScript:
$('#changeUrl').click(function () {
history.pushState({}, 'Title', '/Url/Test');
$(document).load('/url html');
});
Also you can add animation for example :
$('#changeUrl').click(function () {
$('body').fadeOut();
history.pushState({}, 'Title', '/Url/Test');
$(document).load('/url html', function () {
$('body').fadeIn();
});
});
You may also add a JavaScript "fadeout" animation when "unloading" the current page, and a "fadein" animation executing at the begining of the next page load.
If you prefetch most of your content, the transition will be smooth.
To avoid a page load when you click on a link, attach an onclick event to your link, and finish your JavaScript callback by a e.preventDefault(); as explained in this question : How to stop default link click behavior with jQuery from Mozilla Dev Network : https://developer.mozilla.org/en-US/docs/Web/API/event.preventDefault
Cancels the event if it is cancelable, without stopping further propagation of the event.
About link prefetching : https://developer.mozilla.org/en-US/docs/Web/HTTP/Link_prefetching_FAQ
<link rel="prefetch" href="/images/big.jpeg">
Or even really loading <img with a style=display:none; to hide them…
I'm adding a chat feature to a couple of our websites. The chat will connect users with people at our help desk to help them use the websites. Our help desk folks want the chat window to appear like a tab on the side of the page and slide out, rather than popping up in a new window. However, I want to allow the user to navigate around the site without losing the chat.
To do this, I've been trying to move the entire page into an iframe once the chat starts (with the chat outside the iframe), so the user can navigate around the site within the iframe without losing the chat.
I used this answer to get started, and that works great visually. However, some of the javascript in the background breaks.
One of the sites is ASP.NET web forms. The other is MVC. I've been working with the web forms one first. Stuff like calling __doPostBack breaks once the page is moved into the iframe since the javascript context is left behind.
Once the user clicks on a link (a real link, not a __doPostBack) and the iframe refreshes, then everything works perfectly.
How I see it, I have a few options:
Copy all javascript variables from window.top into the iframe somehow. Hopefully without having to know all the variable names. I tried this.contentWindow.__doPostBack = window.top.__doPostBack, which works, but other variables are missing so it ultimately fails:
Somehow switch the iframe's context to look at the top window context, if that's even possible? Probably not.
Another thought was to not move the page into an iframe right away, but to wait until the page changes and then load the new page into a new iframe. But I'm not sure how to hook into that event and highjack it.
Something else?
These are sites for use by our employees only, so I only have to support IE11 and Chrome.
Update:
Thanks to LGSon for putting me on the track of using the target attribute (so I can use approach #3). Below is what I ended up doing. When I pop out the chat, I call loadNextPageInIframe(). I'm using jQuery here since we already use it on our site, but everything could be done without. I set the target on all links that don't already have a target pointing to another frame or _blank. I left _parent out, but I don't think we use it anyway.
I have a reference to my chat window div in a global variable called 'chatwindow'.
There still could be some cases where this doesn't work, such as if there is some javascript that sets window.location directly. If we have anything in our sites that does this, I'll have to add a way to handle it.
function loadNextPageInIframe() {
var frame = $("<iframe id=\"mainframe\" name=\"mainframe\" />").css({
position: "fixed",
top: 0,
left: 0,
width: "100%",
height: "100%",
border: "none",
display: "none"
}).appendTo("body");
$("form, a:not([target]), a[target=''], a[target='_top'], a[target='_self']").attr("target", "mainframe");
var firstload = true;
frame.load(function () {
//Runs every time a new page in the iframe loads
if (firstload) {
$(frame).show();
//Remove all elements from the top window except the iframe and chat window
$("body").children().not(frame).not(window.top.chatwindow).remove();
firstload = false;
}
//Make the browser URL and title reflect the iframe every time it loads a new page
if (this.contentWindow && this.contentWindow.location.href && window.top.location.hostname === this.contentWindow.location.hostname && window.top.location.href !== this.contentWindow.location.href) {
var title = this.contentDocument.title;
document.title = title;
if (window.top.history.replaceState) window.top.history.replaceState(null, title, this.contentWindow.location.href);
}
});
}
May I suggest you do the following
get all links
attach an event click handler to intercept when someone click a link
on click event, check if chat is in progress, and if, feed the iframe with the new link
var links = querySelectorAll("a");
for (var i = 0; i < links.length; i++) {
links[i].addEventListener('click', function(e) {
if (isChatInProgress()) {
e.preventDefault(); //stop the default action
document.getElementById("your_iframe_id").src = e.target.href;
// anything else here, like toggle tabs etc
}
});
}
Update
To handle forms I see 4 ways at the moment
1) Add an onsubmit handler to your forms
function formIsSubmitted(frm) {
if (isChatInProgress()) {
frm.target = "the iframe";
}
return true;
}
<form id="form1" runat="server" onsubmit="return formIsSubmitted(this)">
2) Add a click handler to your buttons
function btnClick(btn) {
if (isChatInProgress()) {
btn.form.target = "the iframe";
}
return true;
}
<asp:Button runat="server" ID="ButtonID" Text="ButtonText"
OnClick="Button_Click" OnClientClick="return btnClick(this);" />
3) When a chat start, you iterate through each form and alter its target attribute
function startChat() {
var forms = querySelectorAll("form");
for (var i = 0; i < forms.length; i++) {
forms[i].target = "the iframe";
});
}
4) Override the original postback event (Src: intercept-postback-event)
// get reference to original postback method before we override it
var __doPostBackOriginal = __doPostBack;
// override
__doPostBack = function (eventTarget, eventArgument) {
if (isChatInProgress()) {
theForm.target = "the iframe";
}
// call original postback
__doPostBackOriginal.call(this, eventTarget, eventArgument);
}
Update 2
The absolute best way to deal with this is of course to use AJAX to load both page and chat content, but that likely means a quite bigger work load if your sites aren't already use it.
If you don't want to do that, you can still use AJAX for chat and if a user were to navigate to a new page, the chat app recreate the ongoing chat window with all its content again.
I suggest instead of loading content to and from iframes - build the chat as an iframe and use a jQuery modal popup on the page for chat.
You can fix the jquery modal to a fixed location and page scrolling is enabled by default. You need to modify css accordingly to make the popup remains on the same location.
If you go down your current path - you will need to worry a lot about how content is moved to the iframe and it might be difficult to re-use the chat on different pages depending on the content. For example, imagine you playing a video on the page and the user clicks chat - if you load the content to the iframe - the user will lose the status on how far he has viewed, etc.
as per my opinion, adding the whole website as an 'I-Frame' is not a good design practice, and not a good solution for the problem. My suggestion would be:
Ensure that the 'Chat' application is loaded in all the pages, across your website
Whenever the 'Chat' is started, either establish the 'web-socket' connection or somehow, maintain the State on the Server
Have the configuration of the 'Chat' as 'Minimized', 'Open' etc and store them in your cookie or session storage
On every page load, call the 'Chat' application too. Read the Chat related configuration from sessionstorage or cookie and maintain it's state as 'Minimized' or 'Open' etc, including the X and Y position, if you want to make it as 'Floated'
Every time, either fetch the entire conversation from the server via Ajax or try to store and fetch from 'Local Storage' and do Ajax only for any Updates from the other party
Use CSS based 'Float' related properties to make it float and sit at some side.
This will ensure that your chat is available for the user and yet he can navigate all through the site.
I am building a website that is navigated through a series of directional buttons. Right and left clicks move between different images associated with one project. Up and down clicks move between projects.
What I am trying to do is ensure that when a user clicks up or down (i.e. between projects) that this is registered as a history traversal event and that a new entry for the new project is visible within the browser's history.
The code that I have sets an event on the the click of the navigation buttons that makes the necessary changes to the pages content, and then I attempt to push the new page to the history object by calling this function (see here and here for background information):
var pushToHistory = function(url, pageTitle, html) {
history.pushState({'html':html, 'pageTitle':pageTitle}, '', url);
}
I supply the arguments to this function elsewhere by doing the following after the page has loaded the new content:
html = document.getElementsByClassName('main-frame')[0].innerHTML
pageTitle = 'http://mysite/'+newpath; // new path specifieds the new item.
this.pushToHistory( url, pageTitle, html);
Now the problem I am having is that the result of all of this is that both in Chrome and in Firefox the history is updated in a way that is mostly correct: the url in the history's state object is correct, as is this the content. So that if I click on one of these history events, the correct page is retrieved.
However, the page title, which is shown in the list of history items is incorrect. It is always the title of the page that was loaded when the site was intially loaded. So if I load mysite/a-project, and the title of the page is "My Site - A Project" that is always what appears in the box. I have also checked my code to ensure that the pageTitle object is correct, so dumping pageTitle before calling history.pushState() shows the correct title.
Any ideas?
I discovered the problem. I needed to set document.title first. That meant somewhere before I call history.pushState(), I needed to do this:
document.title = theNewTitle;
you all have used pinterest, you can see that when you click on any pin, a div is added and lightbox is shown on the same page but the url is changed to that of actual pin page. i have the same lightbox to show data, is it possible to change the url like that?..
one thing i want to tell is that, i have link which has onclick event which calls view() method, in which i am calling another page with ajax request, which shows the content of that page on my page, i want to change url when this link is clicked and back to previous url when closed..here is my code
function view(){
$.get('mypage.jsp', function(html) {
$(html).hide().appendTo('body').fadeIn(500);
}, 'html');
};
This feature is known as HTML5 Push State. Here's a related StackOverflow question which may provide more insight. Good tutorial for using HTML5 History API (Pushstate?)
I haven't checked Pintrest's solution. But is hash what you're looking for?
window.location.hash="Whatever-you-want-to-add-to-the-URL"
This will change http://stackoverflow.com/posts/11968693/ to http://stackoverflow.com/posts/11968693/#Whatever-you-want-to-add-to-the-URL
Yes, with HTML5's new history API. Where the lightbox is triggered, add something like this:
var hist = window.history;
hist.pushState({ image: [IMAGE URL] }, 'lightbox', [URL]);
This will change the current URL without reloading the page, and will create an entry in the browser history, so users can use their browser back button to return to the previous state (in this case, before they opened the lightbox).
You can change the url (not only the hash) by using the pushState or replaceState functions on the history object. More details: http://diveintohtml5.info/history.html
I currently have an iframe within my main page that has a number of checkboxes that need to be actioned prior to leaving the iframe. i.e, if the user commences checking the checkboxes and half way through they then click back on the main page, i.e leaving the iframe, I would like to be able to trap/validate that they have left the iframe and prompt them with a message indicating this, say with a "Note: You will lose all data entered here - Leave: Yes/No?" type message.
Prompting a User to Save When Leaving a Page. This 4guys article sounds like what you need. It talks about the onbeforeunload event. There's some awesome posts here on stackoverflow about onbeforeunload too.
It appears that onbeforeunload indeed does not fire for an iframe. Bugger!
Here's some sample code that should work though. This will only work if you're in the same domain, otherwise same origin policy will prevent the iframe from talking back to the parent.
I also haven't tested these in many browsers so YMMV.
You've got two options here, depending on where you want to put the prompt for changes logic.
Option one involves the iframe telling the parent window when there's changes.
Parent window javascript:
window.onbeforeunload=closeIt;
var changes = false;
function closeIt()
{
if (changes)
{
return "Yo, changes, save 'em?";
}
}
function somethingChanged() {
changes=true;
};
Iframe javascript:
$(function() {
$('input').change(parent.somethingChanged);
});
Option two involves the iframe taking control over the parent window's onbeforeunload
Parent window javascript:
There is none :-)
Iframe javascript:
$(function() {
parent.window.onbeforeunload = myCloseIt;
$('input').change(somethingChanged);
});
var changes = false;
function myCloseIt()
{
if (changes)
{
return "Yo, changes, save 'em?";
}
}
function somethingChanged() {
changes=true;
};
In either option the naive changes variable could be beefed up a bit, probably using techniques from the 4guys article, to see if there's really been any changes.
If they're on different domains, but you're still in charge of "both sides" of the HTML, there's still some options, they're just harder.
xssinterface is a library that uses postMessage and location hashes and secret voodoo black magic to communicate cross site.