jQuery Tabs - Load contents only when clicked - jquery-ui

I am relatively new to jQuery and web development.
I am using jQuery UI Tabs to create tabs.
But I want the contents to be loaded only when I select a particular tab.

OK, I assume when the user clicks a tab, you intend to fetch content dynamically, via AJAX. This really involves two things, setting an onclick even for your tab and fetching the data via ajax.
Setting an onclick event
Give your tab an class, for example my_tab. Let's say that when the user clicks the tab you want the handle_tab_click() function to fire. Here's an example of binding the onclick event to your my_tab tab:
$(".my_tab").bind("click", handle_tab_click);
Your handle_tab_click() function will be given an event argument which will be able to provide you with information on the element that fired the event (in this case, the element with class name my_tab).
function (event) {
if ($(event.target).hasClass("my_tab")) { /* handle tab click */ }
if ($(event.target).hasClass("my_tab_2")) { /* a different tab click */ }
if ($(event.target).hasClass("my_tab_3")) { /* ... */ }
}
See the JQuery event documentation for more details here.
Fetching the data via ajax
Fetching data will require you to invoke a remote script while supplying information about which tab was clicked (in order to fetch the appropriate information). In the following snippet, we're invoking the remote script myscript.php, supplying the HTTP GET argument tab_clicked=my_tab and calling the function tab_fetch_cb when the script returns. The final parameter is the type of data being returned (it's up to you to choose).
$.get("myscript.php", {tab_clicked, "my_tab"}, tab_fetch_cb, "text/json/xml")
It's up to you to design myscript.php to handle the tab_clicked parameter, fetch the appropriate data and return it (i.e. write it back out to the client).
Here's an example for tab_fetch_cb:
function tab_fetch_cb(data, status) {
// populate your newly opened tab with information
// returned from myscript.php here
}
You can read more about the JQuery get function here, and JQuery ajax functions here
I'm sorry I can't be more specific in my examples, but a lot of the processing is really dependant on your task. As it looks as it has already been pointed out, you may look to some JQuery plugins for a canned solution to your problem. That being said, it never hurts to learn how to do this stuff manually w/ JQuery.
Good luck.

UI/Tabs support loading tab content on demand via Ajax, check this example.

Loading content via Ajax adds the complexity of dealing with bookmarking / browser back buttons. Depending on your situation, you should consider loading new content with a full page request. Handling the bookmarking/browser back involves using adding anchor info in the URL.
Also, check out LavaLamp for tab selection. It's pretty nifty looking.

By default a tab widget will swap between tabbed sections onClick, but the events can be changed to onHover through an option. Tab content can be loaded via Ajax by setting an href on a tab.
source: http://docs.jquery.com/UI/Tabs

If you're using Rails, you can try this gem bettertabs
It supports ajax tabs.

Related

Restoring sidebar state in xul

I am creating a sidebar extension which contains a new tab button which adds a new tab containing some elements to the box contained in my sidebar using javascript with the help of document.createElement() function. Now i want to restore the new tabs added by the user while working with the extension the next time my sidebar is loaded after closing along with all the previous values filled in the textboxes. something like the session restore feature of firefox
As i understand, you are talking about tabbox elements.
You actually have two different XUL documents - one redefined in overlay.xul and sidebar's xul document.
I have solved exactly the same issue with sidebar data storing by the following:
All javascript code is stored as main window's object using something like:
var your_javascript_module = (function () {
//your code here
})();
Put module initialization into scripts.js, reference it from overlay.xul
When you open sidebar (and load, let's say sidebar.xul), you can access this object with the following code:
var your_javascript_module =window.QueryInterface(Components.interfaces.nsIInterfaceRequestor)
.getInterface(Components.interfaces.nsIWebNavigation)
.QueryInterface(Components.interfaces.nsIDocShellTreeItem)
.rootTreeItem
.QueryInterface(Components.interfaces.nsIInterfaceRequestor)
.getInterface(Components.interfaces.nsIDOMWindow).your_javascript_module;
Using this, you will have access to all of code from within sidebar.xul scope.
To store taboxe's state - just create some 'storage' object within your_javascript_module and refresh sidebar.xul contents every time sidebar is getting opened.
I'm suggesting putting all javascript into overlay, as it will be always present (until FF is open of course), contrary to the sidebar's scripts that are unloaded on close.
Hope this can still be useful-)

Knockout js registerEvent handler

I'm having a great time playing around with knockout js and have just started to get to grips with adding custom bindingHandlers.
I'm struggling a bit with the update function of a 3rd party jqWidget gauge - I can only get it to animate the first time I update the variable. On each update after that it just sets the value directly.
I don't fully understand ko.utils.registerEventHandler() and what it does although I've seen it in a bunch of other examples. Is this what is causing the animation to break? How do I know which events to register from the 3rd party widget?
For some reason this works fine if I add a jquery ui slider that is also bound to the observable.
You can test this here: set the value a few times to see that it animates the first time and not after that.
http://jsfiddle.net/LkqTU/4531/
When you update the input field, your observable will end up being a string. It looks like the gauge does not like to be updated with a string value, at least after the first time.
So, if you ensure that you are updating it with a number (parseInt, parseFloat, or just + depending on the situation), then it appears to update fine.
Something like:
update: function(element, valueAccessor) {
var gaugeval = parseInt(ko.utils.unwrapObservable(valueAccessor()), 10);
$(element).jqxGauge('value', gaugeval || 0);
}
http://jsfiddle.net/rniemeyer/LkqTU/4532/
You would generally only register event handlers in a scenario like this to react to changes made by a user where you would want to update your view model data. For example, if there was a way for a user to click on the gauge to change the value, then you would want to handle that event and update your view model value accordingly.
I'm answering the
I don't fully understand ko.utils.registerEventHandler() and what it does
part of your question.
registerEventHandler will register your event handler function in a cross-browser compatible way. If you are using jQuery, Knockout will use jQuery's bind function to register the event handler. Otherwise, will use the browser Web API with a consistent behavior across browsers.
You can check it out on the source code.

Dynamically Loading LI's in JQueryMobile 1.0

I've just updated my project from jquerymobile 1.0a1 to version 1.0.
I've encountered a problem with dynamic content. Based on an ajax search I populate an unordered list with list items. Previous the following code refreshed the list so that all the styling appeared correctly:
$('#myContent').find("ul").listview();
$('#myContent').find("ul").listview('refresh');
However as of 1.0 this no longer seems to work.
The list appears but the styling is all wrong and the data-theme on all the elements gets ignored.
Has anyone come across a similar issue with updating and come across the solution.
Updating lists If you add items to a listview, you'll need to call the refresh() method on it to update the styles and create
any nested lists that are added. For example:
$('#mylist').listview('refresh');
Note that the refresh() method only affects new nodes appended to a
list. This is done for performance reasons. Any list items already
enhanced will be ignored by the refresh process. This means that if
you change the contents or attributes on an already enhanced list
item, these won't be reflected. If you want a list item to be updated,
replace it with fresh markup before calling refresh.
http://jquerymobile.com/demos/1.0/docs/lists/docs-lists.html
if #myContent is the listview you can do this:
$('#myContent').listview('refresh');
if #myContent is the page you can do something like this:
$('#myContent').trigger('create');
Create vs. refresh: An important distinction Note that there is an important difference between the create event and refresh method
that some widgets have. The create event is suited for enhancing raw
markup that contains one or more widgets. The refresh method should be
used on existing (already enhanced) widgets that have been manipulated
programmatically and need the UI be updated to match.
For example, if you had a page where you dynamically appended a new
unordered list with data-role=listview attribute after page creation,
triggering create on a parent element of that list would transform it
into a listview styled widget. If more list items were then
programmatically added, calling the listview’s refresh method would
update just those new list items to the enhanced state and leave the
existing list items untouched.
http://jquerymobile.com/demos/1.0/docs/pages/page-scripting.html
What you want can be achieved by replacing your 2 lines of code with the following:
$('#myContent ul').listview('create');
Hope this helps...
I've had this issue. The reason you are getting things all messed up is you are initalizing and refreshing the element multiple times. I noticed I had 2 different functions running that would call .listview('refresh') on the same element. After I took one out the themes and data went back to looking normal. Also are you getting any JS errors?
EDIT:
To be more specific you are calling .listview() somewhere in your code 2 times which is initializing it twice. I would wait to before you page is loaded to run the refresh so you only call it once.
Another thing you could do is check if the element is initialized already or not so you don't do it twice. Just check the element or in some cases the parent to see if the class ui-listview is present.
var element = $('#myContent').find('ul');
if ($(element).hasClass('ui-listview')) {
//Element is already initialized
$(element).listview('refresh');
} else {
//Element has not been initiliazed
$(element).listview().listview('refresh');
}
Just an FYI you can chain those events to look like $('#myContent').find('ul').listview().listview('refresh');
It cand be achived through.
$('#myContent').listview('refresh');
The below snippet shows you to load data from xml and dynamically create a list view.
function loadData()
{
$.ajax({
url:"BirthdayInvitations.xml",
dataType: "xml",
success: function(xml)
{
$(xml).find("event").each(function()
{
$("#mymenu").append('<li>' + this.textContent + ' </li>');
});
$("#mymenu").listview('refresh');
}
});
}
See if this is related to ur question http://www.amitpatil.me/demos/jquery-mobile-twitter-app/ and this one also http://www.amitpatil.me/demos/ipad-online-dictionary-app/
In first example i am using listview('refresh'); method and in second example i am using
$(document).page("destroy").page();

jQuery UI Autocomplete - How to handle AJAX errors?

I'm using the jQuery Autocomplete control to autocomplete from the server via an AJAX call.
I implemented the search event to show a "Loading..." animation while results are being fetched from the server.
I want to disable that animation and show a message if fetching the autocomplete results from the server failed (timeout or whatever)
Whats the best way to do that?
Have a looksie at the jQuery.ajaxError method, which allows you to setup a default error callback for all ajax calls; http://api.jquery.com/ajaxError/
I just find myself in this situation. I wanted to clear the spinner from the textbox, and also highlight it in red, to provide visual feedback of the error. But I have 3 different textboxes in DOM that use the same function. So, you can do something like this:
function autocompleteSource(request,response){
//"this" is the widget object, you can get the element that called the autocomplete function from here
var callerTextbox = $(this.element);
$.get(url,data).done(/*do your stuff with the data*/).fail(function(){
highlight(callerTextbox) //That's my own function, uses jquery animation effects
response([]); //Use an empty response for clear the textbox
});
}

AJAX pattern in Rails for submitting small chunks of data

I have a web page with lots of small images on it. In a typical scenario user clicks on image and expects it to change with a new image.
Requirements:
When user clicks on image, it should be immediately known to a controller in an Ajax way.
Some strings should be passed to a controller when user clicks on image.
Controller does its job and returns another image (which replaces old one).
Along with image controller returns a couple of extra strings (such as completion status).
Web page updates old image with new one and also updates other parts with these new strings.
Number of images on a page varies but potentially it can be a couple of dozens.
Question: What Ajax technique should be used here? I'm quite new to Ajax and don't feel solid with patterns. Should it be Json or something else?
Any code example would be very very welcome and helpful.
Thank you.
Well it sounds like you need a Event observer on the image object. On that image object, you could have various custom attributes, such as imageid="2", etc. With the element being observed onclick, you'd read the attributes of the elements and pass them on to an AJAX call. I'm not sure if the image is known by the database or would it be available on the page itself. Maybe a back/previous button? In either case, the AJAX call could either return JavaScript directly which then gets parsed to update the DOM and replaces the image with the new image source, or it could return a JSON response which then needs to get read and parsed by the AJAX callback and then updates the DOM. Easiest being to return JS code which gets parsed, but I prefer to have all my JavaScript in one file and not have it all over the place mixed with server side code.
It really depends on what AJAX library you are using.
With jQuery, you might do something like this.
$("#buttonImage").click(function () {
var imageid = $(this).attr('imageid');
$.getJSON("/controller/get_image/" + imageid,
function(data){
$("#buttonImage").attr("src", data.imagesrc);
});
});
And your /controller/get_image/123 would return a JSON response like...
{ 'imagesrc' : '/my/image.jpg' }
As far as I known, the only browser-safe way to change an image is by assigning a new URL to it's src attribute. If you return an image to a request that pass some parameters, it might prevent client-side cashing of the images. For these reasons, I would treat separately the transfer of textual data and images.
The completion status can always be return as the HTTP status text but if more information is needed from the server, you can always return it in JSON or XML, the simplest being JSON.
The responsiveness could be improved by preloading images on the mouseover event.

Resources