I am currently working on a website in which the home page displays the most recent 10 blog entries. When I scroll down, and when I reach almost the end of the last item on screen, another 10 blog entries are automatically loaded, and so on (this is the infinite scrolling feature).
If a user clicks on any blog entry, then he/she is taken to another page to display the details about that blog entry. When the user clicks the back button, he/she is taken to the home page that has the entries displayed.
Please note, the home page loads the data using Ajax.
Assume the following scenario:
A user goes to the site, and entries 1 to 10 are loaded (via Ajax).
The user scrolls down, and the next 10 entires, specifically entries 11 to 20 are loaded (via Ajax as well). Note that the page now has entires 1 to 20 displayed.
The user scrolls further down, and now entries 21 through 30 are loaded, for a total of 1 through 30 blog entries being displayed on the page.
The user clicks on entry 25, and the page for entry 25 is displayed.
The user clicks the back button, and all items, 1 through 30 are displayed.
Now, if the users uses FireFox, Opera, or Safari, and when that user performs step 5 (i.e, clicks the back button to go back to the home page) then the blog entries are just displayed on screen, and without being re-loaded. However using IE and on Chrome, when the user clicks on the back button, the page is reloaded, and only items 1 through 10 are displayed.
I do not like the IE and Chrome behaviour. The user should see items 1 though 30. How can I ensure all browsers behave like FireFox?
Thanks.
Update
Here is the code I am using
First, hers is my html
<html>
<body>
<section id="content">
<section id="articles">
<!-- This section is filled by jQuery/Ajax -->
</section>
<section id="loading-spinner">
<img src="ajax-loader.gif" />
</section>
</section>
</body>
</html>
And here is my jQuery
/**
*
* This file uses a bunch of programming concepts, but the most important one is ensuring ajax calls run as a critical section
* ... (this means if ajax is already called, then another instance of JavaScript cannot get into the critical section)
*
* .. For more details, please read: https://mcmap.net/q/1187662/-critical-section-in-javascript-or-jquery
*
*/
load_more_posts = function () {
// If we almost reach the bottom of the document, then load more posts
if ( jQuery(window).scrollTop() >= jQuery(document).height() - jQuery(window).height() - 300) {
// If the value of the promise is not pending, then we can call the load_posts function (the load_posts function will change the status to pending when it is executing the ajax request)
if (ajax_status.state() !== "pending") {
load_posts();
}
}
};
function load_posts() {
ajax_status = jQuery.ajax({
type: 'post',
dataType: 'json',
beforeSend: function(xhr) {
if(jQuery.data(document.body, 'load_page') == false) {
xhr.abort();
}
else {
// Show the spinner
jQuery('#loading-spinner').visible();
}
},
url: '../link/to/get_poasts.php',
data: {
action: 'load_posts',
js_query_data: query_data,
js_page: jQuery.data(document.body, 'page_to_load')
},
success: function (response) {
if (response.isSuccessful) {
var number_of_post_items = response.posts_array.length;
for (var i = 0; i < number_of_post_items; i++) {
// If the item is already returned from the database and posted. then we skip it, otherwise, keep insert a new record
if (jQuery('#articles').find('#article-' + response.posts_array[i].post_id).length == 0) {
// Add 'article'
jQuery('#articles').append('<article id="article-' + response.posts_array[i].post_id + '"></article>');
// More code here to add details about each article, such as title, excerpt...etc.
}
}
// Increase the value of the page to load by 1, and save it.
page = jQuery.data(document.body, "page_to_load");
page = page + 1;
jQuery.data(document.body, "page_to_load", page);
jQuery(window).on('scroll', load_more_posts);
}
else {
// Display error message
jQuery('#articles').append('<div>' + response.message + '</div>');
// Make sure no further AJAX requests are made
jQuery.data(document.body, 'load_page', false);
}
}
}).always(function() {
// Hide the spinner
jQuery('#loading-spinner').invisible();
});
return ajax_status;
}
// Create a new promise. This will be used to ensure that no two calls hit the critical section at the same time
// ... (the critical section in this case is the time when we retrieve data from the database. We only want one call at a time)
var ajax_status = new jQuery.Deferred();
jQuery(document).ready(function() {
// Hide the loading spinner first
jQuery('#loading-spinner').invisible();
// We resolve the promise, making sure it is ready (this is an intial state)
ajax_status.resolve();
// Initial values that are used
jQuery.data(document.body, 'page_to_load', 1);
// This parameter is used to stop loading pages when no more items are available to be displayed
jQuery.data(document.body, 'load_page', true);
// Initial loading of poasts
load_posts();
// Enable on scrolling to load more pasts (to allow infinite scrolling)
jQuery(window).on('scroll', load_more_posts);
});
localStoragethen when your page loads, you could load all the results (0 to 30) from localStorage instead of doing new ajax calls. – Ehrman