Replacing a whole webpage with alternative content (HTML + CSS + JS) - javascript

I am facing a problem that I am sure is pretty common. I found many solutions to this problem, and they all have their pros and cons. I'll post what I found here (which I believe will be useful to others), and I hope you'll point me in the right direction.
Essentially, this is my scenario:
I have a webpage in PHP: http://example.com/page_with_content_a_or_b.php.
This page returns Content A when no POST parameters are specified, and Content B if there are.
Assume a user connects to my page typing the previous URL in her browser (a GET request).
My server returns the page with Content A.
The user's web browser, via JavaScript, decides to replace Content A with Content B.
The question: How does the JavaScript replace the contents?
Well, as I've said, I've been looking for different solutions, but none seems perfect.
In order to discuss each possible solution, let me introduce you the resulting HTML code of each version:
HTML of Content A
<html>
<head>
<link rel="stylesheet" type="text/css" href="style_A.css">
<script type="text/javascript" src="jquery.min.js"></script>
<script type="text/javascript" src="gallery-animator.js"></script>
</head>
<body>
<div class="gallery"><!-- images here --></div>
<p>Content A</p>
<script type="text/javascript" src="content-b-loader.js"></script>
</body>
</html>
HTML of Content B
<html>
<head>
<link rel="stylesheet" type="text/css" href="style_B.css">
<script type="text/javascript" src="jquery.min.js"></script>
<script type="text/javascript" src="gallery-animator.js"></script>
</head>
<body>
<div class="gallery"><!-- images here --></div>
<p>Content B</p>
</body>
</html>
Differences between both versions
As you can see, in the example both versions are quite similar, but not identical. In general, these are the differences I might encounter:
All or some or none imported stylesheets may be different.
All or some or none imported javascripts may be different.
There might be differences with inline stylesheets and/or javascripts.
The content is different, but it may differ a little bit only or be completely different.
Content B does not includes the script for loading itself (last script in Content A).
Possible Solutions
Replacing Content with document.open(), document.write(), and document.close()
The first solution I implemented is the following:
content-b-loader.js (option 1)
$(document).ready(function() {
$.ajax({
type: 'POST',
url: window.location.href,
data: { load_content_b: 'true' },
success: function( html ) {
document.open();
document.write(html);
document.close();
}
});
});
Apparently, the solution works properly. However, there are situations in which I have problems. In my example, for instance, both contents load a script named gallery-animator.js. Assuming this script is the following:
gallery-animator.js
var galleryInterval = setInterval(function() {
// Fade out current image and fade in the next one
$("body > div.gallery > img")...
}, 5000);
after executing the script in content-b-loader.js there are two timeouts animating the gallery. As a result, the animation looks like a mess (two images moving at the same time, or not working at all).
It looks like the sequence document.open(), document.write(html), and document.close() does not stop and replace the original scripts.
Redirecting with POST data (using a form)
Another solution is doing a redirection described in this previous question. The solution works like a charm: on the one hand, I load the URL I need to load with the required POST data, which means I'll get Content B, and on the other hand, Content B is loaded in a "new page", which means that the scripts loaded by Content A are no longer there.
The problem here? If I refresh the page with Content B, I get a warning stating that "POST data is about to be resubmitted". This is undesirable, because it looks confusing for the user (I don't want her to know she had been redirected to a new page).
I know there's a solution called PRG (Post-Redirect-Get) which avoids this particular issue. However, it requires Content B to be accessible using a GET request (using GET params or COOKIES, neither of which I can use).
Using iframes
The last solution I've found is also interesting. Basically, it hides (or empties) the body from Content A, adds an iframe in the page, and loads Content B inside it:
content-b-loader.js (option 3)
$(document).ready(function() {
$.ajax({
type: 'POST',
url: window.location.href,
data: { load_content_b: 'true' },
success: function( html ) {
$("body").css('', ''); // Remove all paddings and margins
$("body").empty();
$("body")append('<iframe id="content" seamless="seamless"' +
'src="anchor.html"></iframe>');
// Initialize vars in anchor.html and call the redirect functions
document.getElementById('content').contentWindow.url = window.location.href;
document.getElementById('content').contentWindow.options = {
load_content_b: 'true'
};
document.getElementById('content').contentWindow.redirect();
}
});
});
anchor.html
This page implements the second solution (it uses a POST redirect).
<html>
<head>
<script type="text/javascript" src="jquery.min.js"></script>
<script type="text/javascript" src="jquery.redirect.min.js"></script>
<script type="text/javascript">
var url;
var options;
function redirect(){
$().redirect(url, options, 'POST');
}
</script>
</head>
<body></body>
</html>
By making the iframe as big as the window view, I can show the alternative content. If the user refreshes the webpage, the page that is refreshed is the "container" page (the one that originally had Content A), so no warnings appear at all.
The problems I am facing with this solution, however, are:
Users can disable iframes. How do I detect whether iframes are enabled or disabled?
When the user clicks a link in the frame (or submits a form), the "new page" is opened inside the iframe. This is not what I want: I want it to be opened in the main window. How do I do this? I know that there is the base directive for links... but what about forms? And JavaScript code that performs a redirection?
Does everything work properly inside iframes? Responsive themes, javascripts, ... As far as I can tell, they do, but I ignore whether users can limit what iframes can do.
TL;DR - Conclusions
I have a page http://example.com/page_with_content_a_or_b.php. The page returns Content A when accessed using a GET request, and returns Content B when accessed using POST. When user types the URL, she gets Content A, and Content B is loaded using JavaScript.
All solutions entail problems:
With document.open(), document.write(), document.close(), scripts get messed.
With POST redirections, refreshing the page popups a warning
With iframes, they are not always available, and I am somehow "stucked" inside them.
Any ideas? Am I missing something? Is there a preferred way to do what I'm trying to do?
Thank you very much!

There's a hacky fix for the problem with messy script behavior in your first solution. Assuming that the script-related problem only occurs when using timeouts (I don't know if there are other scenarios in which things can go wrong....), there's an easy way to clear all timeouts. Just add this code:
var id = window.setTimeout(function() {}, 0);
while (id--)
window.clearTimeout(id);

A POST request should do things which change or affect data. Thus it makes sense to prevent the user from refreshing and that should be desirable behavior, I am confused whether you're doing an actual post request or otherwise why is redirecting to a POST page is so problematic?
Either way, regarding your <iframe> solution, let me give some suggestions. "Disabling iframes" is indeed technically possible on some browsers, but to do such a thing you have to either dive in about:config or very deep in the IE menu and it's entirely impossible on Chrome by default. So yeah, truth be said, I would not concern myself with that whatsoever, just like nowadays most sites do not concern themselves with users who disable javascript (any user with disabled iframes will probably have javascript disabled as well btw), simply because it's too rare to concern yourself with and it's one of those choices where you have to face the consequences yourself. Now, I was planning on directing you to the <base> tag as well, just realizing now that you already mentioned it in your post. Either way, the tag will work for forms as well, but not for javascript 'links'.
All in all I would advice you to rethink whether the page should be POST, if so, then you should just go with the warning and otherwise rework it to be just another GET page.

I guess I'm missing something, because I don't clearly understand what do you mean by "The user's web browser, via JavaScript, decides to replace Content A with Content B", but:
If you know in advance the parameters of the elements whose content you'd like to replace, wouldn't a simple case by case replacement work?
<html>
<head>
<link rel="stylesheet" type="text/css" href="style_A.css">
</head>
<body>
<div class="gallery"><!-- images here --></div>
<p class="content">Content A</p>
</body>
<!-- This could be content-b-loader.js -->
<script>
var $stylesheet = document.getElementsByTagName('link')[0];
$content = document.querySelectorAll('.content')[0];
if ( $stylesheet && $content ) {
if ( $stylesheet.getAttribute('href') == 'style_A.css' ) {
$stylesheet.setAttribute('href', 'style_B.css');
}
$content.innerHTML = 'Content B';
}
</script>
</html>

Related

Force re-firing of all (scripts / functions) on ajaxed content

tl;dr
I use ajax to fetch new content. The content is fetched and added to the page. However, scripts don't "re-fire" because their calls are outside of the ajaxed div.
The scripts load and fire without any problem on initial page load but not when I add new content via ajax. I get no console errors and there are no issues if I visit the URL directly.
Related:
Forcing Script To Run In AJAX Loaded Page - Relates to one specific script. I want to fix (refire) all scripts including dynamic ones from Cloudflare apps
Using jQuery script with Ajax in Wordpress - Same as above, this relates only to one specific script
ajax loaded content, script is not executing
Intro:
I use Ajaxify WordPress Site(AWS) on a WordPress website.
The plugin lets you select a div by its id and then fetches new content inside that div using ajax
html markup
<html>
<head></head>
<body>
<div id="page">
<header></header>
<main id="ajax"> <!-- This is what I want to ajaxify -->
<div class="container">
main page content
</div>
</main> <!-- end of ajaxfied content -->
<footer></footer>
</div> <!-- #page -->
</body>
</html>
Problem
The plugin works and I get fresh content loaded and styled but there is an issue. Some of my page scripts and function calls are outside of the div that I use ajax on. I have two examples
1- Masonry is loaded and called in the <footer>
<html>
<head></head>
<body>
<div id="page">
<header></header>
<main id="ajax"> <!-- This is what I want to ajaxify -->
<div class="container">
main page content
</div>
</main> <!-- end of ajaxfied content -->
<footer></footer> <!-- Masonry script is loaded and called here -->
</div> <!-- #page -->
</body>
</html>
2- Google maps call is in the <head>
<html>
<head></head> <!-- Google maps is called here -->
<body>
<div id="page">
<header></header>
<main id="ajax"> <!-- This is what I want to ajaxify -->
<div class="container">
main page content
</div>
</main> <!-- end of ajaxfied content -->
<footer></footer>
</div> <!-- #page -->
</body>
</html>
These are just two examples. There are others in other locations. As you can tell, such scripts won't be re-called as the only thing that reloads on the page is <main id="ajax">. While the new content inside <main> is there, some of the scripts required to render it properly are not re-called and so I end up with missing elements / broken layout.
I am not the only one who has faced this problem; a quick look at the plugin's support forum on wordpress.org shows that this issue is common.
Note: I wouldn't try to fix this if the plugin had many other issues. It works for me I just need the scripts to re-fire.
The official response is that it's possible to reload / re-fire scripts by adding the following into the plugin's php files:
$.getScript(rootUrl + 'PATH TO SCRIPT');
Which works. It works well. for example if I add
$.getScript(rootUrl + '/Assets/masonry.js');
Then the masonry function calls get re-fired when the ajaxed content is fetched even if masonry.js is loaded outside of the ajaxed div
I refer you to the plugin's files on github for more clarity on what the fix actually does (I can't make sense of what happens when $.getScript is used)
In summary
The official fix works fine if you have 3-4 scripts that need to be re-fired on ajaxed content.
This does not work for my goal because
it's too rigid and hard-coded
Some of the scripts are added to the page dynamically via Cloudflare apps
A possible solution might involve adding an event mimics the trigger that causes the scripts to fire at the bottom of the ajaxed div
Question:
How do I force all scripts - including dynamically added ones - to re-fire when only a certain part of the page has been reloaded via ajax?
Notes:
I am trying to avoid calling out scripts one by one as that would require knowledge of their calls before hand. I am probably talking way over my head but...
I am trying to mimic the page load and / or document ready events - at which most conditional scripts are fired (correct me if I'm wrong) - at the end of <main> in my html when new ajaxed content is added but without affecting the document when the page is loaded via using the url directly...or any other similar approach.
Just for a bit of context, here is a list of some the event listeners on the page while the plugin is off. I know there are things in there I won't have to trigger. I just added this for reference. Also, please note that this is a sample taken from one of the pages. other pages may differ.
DOMContentLoaded
beforeunload
blur
click
focus
focusin
focusout
hashchange
keydown
keyup
load
message
mousedown
mousemove
mouseout
mouseover
mouseup
mousewheel
orientationchange
readystatechange
resize
scroll
submit
touchscreen
unload
The solution you choose here will have to depend on how the scripts are initialized. There are a couple common possibilities:
The script's actions are evoked immediately upon loading of the script. In this case, the script might look something like this:
(function() {
console.log('Running script...');
})();
The script's actions are evoked in response to some event (such as document ready (JQuery) or window onload (JavaScript) events). In this case, the script might look something like this:
$(window).on('load', function() {
console.log('Running script...');
});
Some options for these two possibilities are considered below.
For scripts that run immediately on loading
One option would be to just remove the <script> elements you want to trigger from the DOM and then reattach them. With JQuery, you could do
$('script').remove().appendTo('html');
Of course, if the above snippet is itself in a <script> tag, then you will create an infinite loop of constantly detaching and re-attaching all the scripts. In addition, there may be some scripts you don't want to re-run. In this case, you can add classes to the scripts to select them either positively or negatively. For instance,
// Positively select scripts with class 'reload-on-ajax'
$('script.reload-on-ajax').remove().appendTo('html');
// Negatively select scripts with class 'no-reload'
$('script').not('no-reload').remove().appendTo('html')
In your case, you would place one of the above snippets in the event handler for AJAX completion. The following example uses a button-click in lieu of an AJAX completion event, but the concept is the same (note that this example doesn't work well within the StackOverflow sandbox, so try loading it as a separate page for the best result):
<html>
<head></head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script class="reload-on-ajax">
console.log('Script after head run.');
</script>
<body>
<button id="reload-scripts-button">Reload Scripts</button>
</body>
<script class="reload-on-ajax">
console.log('Script after body run.');
</script>
<script>
$('#reload-scripts-button').click( () => $('script.reload-on-ajax').remove().appendTo('html') );
</script>
</html>
Note that if the scripts are not inline (e.g. fetched via the src attribute), then they will be reloaded from the server or retrieved from browser cache, depending on the browser and settings. In this case, the best approach is probably to remove all the <script>s that operate on the AJAX-loaded content, and load/run them via something like JQuery's getScript() function from an AJAX completion event handler. This way you will only be loading/running the scripts once at the appropriate time (i.e. after the AJAX content is loaded):
// In AJAX success event handler
$.getScript('script1.js');
$.getScript('script2.js');
A potential problem with both variants of this approach is that asynchronous loading of the script is subject to cross-origin restrictions. So if the scripts are hosted on a different domain and cross-origin requests are not allowed, it won't work.
For scripts that run in response to an event
If the scripts are triggered on window load, then you can just trigger this event:
$(window).trigger('load');
Unfortunately, if the scripts themselves use JQuery's document ready event, then I'm not aware of an easy way to trigger it manually. It's also possible that the scripts run in response to some other event.
Obviously, you can combine the above approaches as necessary. And, as others have mentioned, if there's some initialization functions in the scripts that you could just call, then that's the cleanest way.
If you can identify a global initialising function or code block in your external scripts, you could take a look at the 'ajaxComplete' event. You can put this code in your page head and put the initialising function calls or code blocks inside the ajaxComplete callback.
$(document).ajaxComplete(function(){
module1.init();
$('#my_id').module2_init({
foo : 'bar',
baz : 123
});
});
When the scripts you are talking about don't have such easy-to-use exposed initialising functions, but initialise themselves on scriptload, I think there will be no out of the box method that works for all scripts.
Here's what you can try -
Most of the scripts like masonry or Google Map are set to re-init on window resize. So, if you trigger the resize event after ajax complete, it will help to re-fire those scripts automatically.
Try the following code -
$( document ).ajaxComplete( function() {
$( window ).trigger('resize');
} );
This will force the scripts to re-init once ajax is completed as it will now trigger the resize event after the content is loaded.
Maybe risky, but you should be able to use DOMSubtreeModified on your <main> element for this.
$('#ajaxed').bind('DOMSubtreeModified', function(){
//your reload code
});
Then you should be able to just append all your scripts again in your reload area
var scripts = document.getElementsByTagName('script');
for (var i=0;i<scripts.length;i++){
var src = scripts[i].src;
var sTag = document.createElement('script');
sTag.type = 'text/javascript';
sTag.src = src;
$('head').append(sTag);
}
Another option could be create your own event listener and have the same reload code in it.
$(document).on('ajaxContentLoaded', function(){//same reload code});
Then you could trigger an event in the plugin once the content had been updated.
$(document).trigger('ajaxContentLoaded');
Or possibly a combination of editing the plugin to trigger a listener and adding to your codebase to re-run anything you feel you need to have re-ran off that listener, rather than reload anything.
$(document).on('ajaxContentLoaded', function(){
//Javascript object re-initialization
myObj.init();
//Just a portion of my Javascript?
myObj.somePortion();
});
A solution could be duplicating all the scripts...
$(document).ajaxSuccess((event, xhr, settings) => {
// check if the request is your reload content
if(settings.url !== "myReloadedContentCall") {
return;
}
return window
.setTimeout(rejs, 100)
;
});
function rejs() {
const scripts = $('script[src]');
// or, maybe alls but not child of #ajax
// const scripts = $('*:not(#ajax) script[src]');
Array
.prototype
.forEach
.call(scripts, (script, index) => {
const $script = $(script);
const s = $('<script />', {
src: $script.attr('src')
});
// const s = $script.clone(); // should also work
return s
.insertAfter($script)
.promise()
.then(() => $script.remove()) // finally remove it
;
})
;
}
I had this exact problem when attempting to use ajax to reload a page with browser states and history.js, in wordpress. I enqueued history.js directly, instead of using a plugin to do that for me.
I had tons of JS that needed to be "re-ran" whenever a new page was clicked. To do this, I created a global function in my main javascript file called global_scripts();
Firstly, make sure this JS file is enqueued after everything else, in your footer.php.
That could look something like this:
wp_enqueue_script('ajax_js', 'url/to/file.js', 'google-maps', 1, true);
My javascript that I enqueue is below.
jQuery(document).ready(function($) {
// scripts that need to be called on every page load
window.global_scripts = function(reload) {
// Below are samples of the javascript I ran that I needed to re run.
// This includes lazy image loading, paragraph truncation.
/* I would put your masonry and google maps code in here. */
bLazy = new Blazy({
selector: '.featured-image:not(.no-blazy), .blazy', // all images
offset: 100
});
/* truncate meeeee */
$('.post-wrapper .post-info .dotdotdot').dotdotdot({
watch: 'window'
});
}
// call the method on initial page load (optional)
//global_scripts();
});
I then hooked into the JS that ran whenever a page was loaded with history.js and called global_scripts();
It seems as though the plugin you are using also uses history.js. I haven't tested it with your plugin specifically, but you can try what I posted below (which is what I use in my app).
This would go in the same JS file above.
History.Adapter.bind(window, 'statechange', function() {
global_scripts();
}
My code is a bit more complicated than what is simply pasted above. I actually check the event to determine what content is being loaded, and load specific JS functions based on that. It allows for more control over what gets reloaded.
note: I use window.global_scripts when declaring the function because I have separate JS files that hold this code. You could chose to remove this if they are all in the same.
note2: I realize this answer requires knowing exactly what needs to be reloaded, so it ignores your last note, which asks that this doesn't require such knowledge. It may still help you find your answer though.
Short answer:
It is not possible to this in a generic way. How should your script know which events needs to be fired?
Longer answer:
It is more like a structural question than a programmatic one. Who is responsible for the desired functionality? Lets take masonry as an example:
Masonry.js itself does not listen to any events. You need to create a masonry instance by your own (which is most probably done on domready in your Wordpress plugin). If you enable the resize option it will add a listener to the resize event. But what you actually want is some listener on "DOM content change" (see https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver for possible solution). Since masonry.js does not provide such a function you have the following options:
Wait for the implementation (or do it yourself) in masonry.js
Wait for the implementation (or do it yourself) in masonry Wordpress plugin.
Add the functionality somewhere else (your template, your ajax plugin, etc.)
4.
As you can see every option includes some work to be done and this work needs to be done for every script you want to listen to your AJAX invoked DOM changes.

Including PHP depending on screen width size

I read a lot about it, I tried a lot as well... I almost think it's possible, but I need your help.
I want to load some content depending on the screen width. It's a sticky navbar with social network sharing buttons (follow on twitter, like on facebook, the usual).
Using this code, It loads the html, perfectly. BUT the scripts inside it, does not. I use jQuery animation to show the buttons when the cursor is over the logo, and the buttons use javascript to, well, work. But, loading this way, it's like there was no scripts inside that html.
$(function () {
var width = $(window).width();
if (document.documentElement.clientWidth >= 992)
$('#Navbar').load('navbar.html');
});
I tried with PHP, then. A simple include() worked. The navbar was loaded the way it was supposed to.
Since PHP cannot know the screen width (and since I am using bootstrap, I following it's screen sizes), I thought I could do this (I changed the .html to .php, it's all the same)
$('#NavBar').append('<?php include "navbar.php"; ?>');
But it doesn't work.
Is there a way for me, using jQuery, to call the include()? Or any other way that could make this work?
Media queries and display: hidden are not options. I don't want to load the content and keep it hidden. I want to just load it when it's needed.
These are two completely different programming languages so you can't call a php function from your javascript.
but you can call a reload of the page with some parameters or some kind of new url to make this work with php.
Example onepage php site:
<html>
<head>
<!--Your Stuff-->
</head>
<body>
<?php
//access the parameter and it's value with php's global $_GET
if(isset($_GET["mobile"]) && $_GET["mobile"] == 992){
include "navbar.php";
}
?>
<script>
//check if the document has the specified width and also if the parameter is already set
if (document.documentElement.clientWidth >= 992 && window.location.href.indexOf("?mobile=992") == -1) {
window.location.href = window.location.href + "?mobile=992";
}
</script>
</body>
</html>
The Example above works if you don't have any additional get parameters on the site and navbar.php only contains valid html stuff.

Reloading a Page (or part of a page) using JavaScript

The client I am working for is trying to make it so that his page never has to reload. Instead he just wants to use AJAX. Now I realize that the way im doing it is not a very efficient way to do it but it is the easiest and you would understand why if you would see his site..
I'm trying to get it to work so that AJAX will refresh only parts of the page or the whole page.
My code is:
<!doctype html>
<html>
<head>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js" type="text/javascript"></script>
<script>
function refresh (update) {
$.get(location.href, function (data) {
console.log(data);
var EL = $(data).find(update);
var HTML = $('<div>').append(EL.clone()).html()
alert(HTML);
$(update).replaceWith(HTML);
});
}
</script>
</head>
<body>
<div style="font-size: 64px;">The current timestamp is <b class="time"><?php echo rand(999, 9999999); ?></b></div>
<br><br>
<button onclick="refresh('.time')">Refresh Time</button>
</body>
</html>
When you first load the page PHP generates a random number. Hitting the refresh button is suppose to refresh this number. However, the same number stays there. The request returns the exact same page instead of return a page with a new number.
And again, people note that I know this is not a very efficient way to do this, but its the way i'm trying to get it to work
Am I doing something wrong? (besides requesting the whole page when only actually using part)
EDIT
You can try it out here: http://methods.x10.mx/projects/refreshPageParts.php
Change your call to this, to break the caching:
function refresh (update) {
$.ajax({
type: "get",
cache: false,
url: location.href,
success: function (data) {
$(update).replaceWith($(data).find(update));
}
});
}
See the notes on caching in the documentation: http://api.jquery.com/jQuery.ajax/
By default, requests are always issued, but the browser may serve results out of its cache. To disallow use of the cached results, set cache to false. To cause the request to report failure if the asset has not been modified since the last request, set ifModified to true.
I tested your example on my local wamp stack and it is working fine!
btw: you forgot semicolon after the following line (It is not necessary though)
var HTML = $('<div>').append(EL.clone()).html();
EDIT: your code is working... also on the url you provided. The strange thing is you have to wait a few minutes before it is working. So when you visit the page and press the button, the time won't be updated... however if you wait few minutes it will... only once then you have to wait again. I bet your server is caching the page. So your problem is server side... disable the cache and it will work!!
EDIT:
you also could try to make the get url dynamic with a dummy parameter like so
http://methods.x10.mx/projects/refreshPageParts.php?v=dummy
maybe you don't have to make dummy dynamic, it might work with a static variable also. i'm curious, let me know ;-)

Data transition = Slide not working -dynamic list

I am new to Jquery mobile.
I am trying to get Sliding effect when i navigate to another page say # display2 from thie below code.
but i am not able to get slide effect.
If I remove the rel="external" i am able to slide but on the #display2(page whihc i would navigate to),the query string values are returned as null.
so if i put rel="external" the parameters are passed to #display2 but slide transition not working.
if i remove re="external" slide works but the querystring parameters are returned null.
can you please let me know is there a way where both of them work together.
('#display').on('pagebeforeshow', function () {
// $(this).find('[data-role=header] .ui-title').text(json.getLOBXMLResult[currentItem].FolderName);
$.ajax("AppstoreWS.svc/getLOBXML", {
beforeSend: function (xhr) {
$.mobile.showPageLoadingMsg();
},
complete: function () {
$.mobile.hidePageLoadingMsg();
},
contentType: 'application/json',
dataType: 'json',
type: 'GET',
error: function () {
//alert('Something awful happened');
},
success: function (data) {
result1 = data.getLOBXMLResult;
$('#categoryList').children().remove('li');
$.each(result1, function (index, output) {
$('#categoryList').append('<li>' + output.FolderName + '</li>');
});
$('#categoryList').listview('refresh');
}
});
});
Part 1 - why rel=external worked & other options
The reason why rel=external works with no transition is because this expects the browser to open an external page and therefore, disable ajax. To counter-effect this, you've got numerous options :
By using Single page template
You could make your two pages into a single page. This is called a single page template and your second page's reference would be #page2 (or any name you'd give as the ID). This is how it'd look like :
<div data-role="page" id="page1">
<!--Stuff in page 1-->
</div>
<div data-role="page" id="page2">
<!--page 2 stuff-->
</div>
Advantages
The DOM can leverage the power of ajax driven navigation.
This would make partial loading, script loading easy, as you'll need to refer all this only once.
Data-transfer between pages is very simple. You'll just have to store the data in you need in a global variable or in the data property of the #page2, and retrieve it in the pageinit or pageshow (or any event) of the second page.
Transitions, etc will work.
There will be no page refresh.
Disadvantages
If the HTML content of the two pages are large, it'll be difficult for maintenance.
By using rel=external
As you might have seen, rel=external can be used only when a page refresh is absolutely needed. Its upto the user's choice. If an a tag is marked with rel=external it means the browser will treat it as an external link, and will ignore jQuery Mobile's ajax navigation system.
By referring all the scripts of page 2 in page 1
Generally, to be able to use page transitions, you must use ajax system of navigation in jQM. So the general behaviour of ajax is as follows :
page1 will request for page2 in page2.html.
The <body> of page2.html alone is taken from page2.html.
The <head> section( which might contain your scripts, which might have your query-string logic) will be ignored.
So to change this, you can refer to page2's scripts in page1.html's head so that these scripts will be loaded and ready when jQM's ajax system pulls the body of page2.html.
<script src="jqm.js"></script>
<script src="page1.js"></script>
<!--page 2 scripts-->
<script src="page2.js"></script>
Advantages
Your transitions will be working properly.
The common scripts will not be referred to multiple times, hence much faster loading times.
Query strings will also work
Disadvantages
If the two pages have very little in common, you'll end up having unwanted scripts in your first page.
What if you have more than two pages? What if you have 10 pages? Will you refer to all 10 pages' scripts in page1. I dont think thats the way.
By referring to page2 scripts inside "data-role=page" section of page2.html (recommended)
This will bring the scripts along with the page when ajax brings it in. This will also work with query strings. This will look something like this :
<div data-role="page" id="page2">
<script src="page2.js"></script>
<!--- your html-->
</div>
Advantages
The scripts pertaining to a particular page are restricted to within that page.
Transitions will work.
Query strings will also work
Part 2 - alternative to query string
The reason I'm saying this because Query strings are archaic technology, because at that time, there was no way to store to data. They're also insecure because user can see the data you send over the URL. You must consider using something like localStorage. I'm not saying you must NOT use query strings. It's just that there are better options available for mobile data storage. See this link for more info about how you can use this localStorage. Also, see this for all the options you have. Now, looking at your query string :
platform=' + output.FolderName + '&sid=test
This could easily be made into an object. So in the click function of the anchor tag inside <li>,
$(document).on("click", "li a", function(e) {
//stop default action.
e.preventDefault();
//take the href; Im assuming its page2.html?platform=outputFolder&sid=test
var params = this.href.split("?");
//now params[0] = page2.html
//param[1] = platform=outputFolder&sid=test
//set this in localStorage
localStorage["page2params"] = param[1];
//change to page2.html
$.mobile.changePage("page2.html", { transition : slide });
})
Then, in the page2.html's pageinit method, you could retrieve it for your use :
//assuming you have a page with page2 as id in page2.html
$(document).on("pageinit", "#page2", function() {
var params = localStorage["page2params"];
//do anything you want with params.
});

How to realize screens / views with JavaScript / Jquery easily?

I'm sure I'm missing something pretty basic, but I have just started to get myself up to speed on jQuery and Javascript programming. Previously I was doing server side programming with PHP.
I'm now in the middle of creating a prototype for HTML5 webapp, where I would like to have different screens. Now with PHP that was pretty easy, I could just used server side templates like Smarty and be done with it.
However to make my app more webapp like, I would like to dynamically change between screens without having to reload the window.
I have looked into several options that might be anwsers to my question, but I'm not sure whether I'm on the right track.
I have checked for example JsRender, JsViews or even the pure jquery load command.
But what I'm not sure is whether these things would allow me to have something like this:
HEADER_PART
MAIN_CONTENT
FOOTER_PART (also contains links to common JS files that I use)
I would like to dynamically update the MAIN_CONTENT part. Currently my application is only one page, and all my custom logic that belongs to that page is in one JS file. In this JS file, I use a simple $(function() { ... to load my page, so whenever it gets loaded, parts of my page get updated asyncronously. This is fine, since all my blocks in this certain page would have to be loaded when that one page gets loaded.
But what if I have a link, like main.html#otherscreen, and when I click that screen, I would like to change my MAIN_CONTENT and also run another page load specific JS that handles blocks on that other screen, not the first page?
I know I could still use probably server side templating and load my pages using AJAX requrests, but again, not sure whether that is the right approach.
Could you please enlighten me? :)
Thanks & best regards,
Bence
Check out jQuery.load(). Using this function you can dynamically load content into a div on the page, which is what I think you want to do. Just find the div on the page you want to load content into and call
$('#mydiv').load(url, data, function(response){
//do something once it's done.
});
Per your comments...
This is actually very easy. .load() should replace the content in the div (I think. If not, just call .empty() first). Of course you could get fancy and add effects, like
function changePages(url) {
$('#mydiv').fadeOut('fast', function() {
$(this).load(url, function(response){
$('#mydiv').fadeIn('fast');
});
});
}
To handle things like the hash in the URL, in your click event you have to make sure you first call e.preventDefault():
$('#mylink').click(function(e){
e.preventDefault(); //e is a jquery event object
var link = $(this);
var hash = link.attr('href'); // get the hashtag if the href is '#something'
changePages(someUrl + hash);
});
For dynamic loading of data into the page without changing your header and footer you should use jQuery's AJAX function. It allows you to post requests to the server and receive data back without reloading the page. A simple example would be something like:
<html>
<head>
<title>Example</title>
<!-- Assuming jQuery is already referenced -->
<script type="text/javascript">
$('span.buttonish').click(function(){
$.ajax({
// The URL can be a file or a PHP script of your choosing
// it can also be pure HTML without the <html> tags as they
// are already in your file
url: 'path/to/the/file/that/return/data',
success: function(receivedData) {
// The received data is the content of the file or the return
// data of the script and you can use it as you would with any data
$('#content').html(receivedData);
}
});
});
</script>
</head>
<body>
<div id="header">
<!-- Something -->
</div>
<div id="content">
<span class="buttonish">Click me to change the text... </span>
</div>
</div id="footer">
<!-- Something -->
</div>
</body>
<html>

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