I don't have the means to test this right now but I am curious. Using AJAX, can you open the same file that the AJAX call was on? My goal is to pretty much reload the page, with a new POST parameter, without refreshing and using only one file.
Yes you can.
I just ask you, why don't, instead of reloading the page, you reload/rebuild/destroy and create the elements you need based on the response to that ajax call ? depending on your desired outcome you might want to do it better like that. More work in the user side, but a nicer 'web 2.0' experience.
Related
I want to update my PHP GUI view when my data source is updated(data source can be a database). I'm having a hard time understanding how I can do this without reloading the whole view for the user.
What I try to achieve is:
Users view are shown, from an handheld device call a script on the site and the script updates a data source, when data source is updated, update the users view with this updated data without reloading.
Is this possible with PHP/JS and how would I achieve this? I do not need any code but more step by step explanation and perhaps what technology to use.
Appreciate any suggestion that leads me forward with this problem.
Best regards,
Gabriel Paulsson
Use ajax for refreshing data when any event happens. The page will not reload by using ajax. It is very simple to use ajax. Googel, gmail and many other use such ajax. Learn in ten minutes form w3school http://www.w3schools.com/ajax/default.asp
It should be possible to do it just with php, telling the page to update itself at a certain interval.
The way I would do it, is to use javascript with ajax and a timed event. The event fires of an ajax call to the server, the server returns any new information.
If you are new to ajax, you probably want to use a library to make things a bit easier to handle. My personal favourite is prototype.js, although at the moment that seems to be a bit "on the way out" and eg jquery may be a better alternative.
I want to put Thumbs up/Thumbs down buttons on my website.
There will be quite a few of them displayed at once, so I don't want to have to do a POST and reload the page every time the user clicks on one.
I thought of using re-skinned radio buttons to choose Thumbs up/Thumbs down, but that would require the user to click a submit button.
So how do I do this? I am open to using JavaScript or some other form of Client-Side scripting, so long as it is built in to most/all web browsers.
Thanks!
YM
I would take a look at using jQuery, http://jquery.com/ It is a WIDELY used library and there is tons of support for it both here and # jQuery's website.
You could easily assign all those thumbs to do an ajax post to a save page with the correct id and the user would not know the difference
You're definitely going to need to use JavaScript on this. Well, there are other client-side languages that could technically do the job (ActionScript, for example), but JavaScript is definitely the best way to go.
Look into AJAX (Asynchronous JavaScript And XML). This is just a buzzwordy way of saying use the XMLHttpRequest() object to make page requests with JavaScript without reloading the page. Here's a good tutorial: http://www.w3schools.com/ajax/default.asp . Note that, despite the word "XML" being in the title, you don't have to use XML at all, and in many cases you won't.
What you'll basically do is this:
Have your thumbs-up and thumbs-down buttons linked to a JavaScript function (passing in whether it's a like or dislike via a function argument).
In that function, send a request to another page you create (a PHP script) which records the like/dislike. Optionally, you can have the PHP script echo out the new vote totals.
(optional) If you decided to have your PHP script output the new results, you can read that into JavaScript. You'll get the exact text of the PHP script's page output, so plan ahead according to that -- you can have the PHP script output the new vote totals in a user-friendly way and then just have your JavaScript replace a particular div with that output, for example.
I am working on a social network website similar to facebook. But, I am facing a rather confusing stage in the programming.
I am done with the register/login/logout pages/scripts, and you can view profiles with the www.mywebsite.com/profile.php.
Now, I want to do what facebook does and allow users to click links while on their profile page (info, notes, photos) but never actually leave www.mywebsite.com/profile.php — just the appropriate content is printed to the screen.
How is this done? I am not asking anyone to code this for me, just point me in the right direction!
You can use Ajax for this purpose.
Put the content that you want to replace in a div and using ajax replace that div and only send that content.
Are you trying to do something like this?
http://www.99points.info/2010/05/how-to-create-dynamic-content-loading-using-ajax-jquery/
That will have to be done via Javascript and Ajax.
A javascript function will fire when the link is clicked. An ajax request is sent to the corresponding php script which sends back a response to your javascript function. You then parse this response and place it on the screen.
If you go that way, have a fallback option that does not rely on javascript as well in case a user has JS turned off.
You Can use this reference...
function showdiv(id)
{
if(id)
{
var selected_offer="yourpagename.php"
HTML_AJAX.replace('divname',selected_offer);
}
}
call showdiv on onChange() function of your link..
For this, you need the technique known as Ajax, which is short for asynchronous JavaScript and XML. The basic idea is that when the user does something - in your case clicks on a link or button - instead of loading a page, a script runs that calls on a server side script to send back some data. This is sometime XML, but you can get other types of data back as well. The asynchronous part is that the user and the page can go on doing other things while waiting on your script to return the data you asked for.
There's a good book for beginners in Ajax that I read myself: Head First Ajax. Looks like you can pick up a used copy for about $10. It's a nice intro, has a quirky style that appeals to some, and the authors do whatever they can to keep your attention. Hardcore programmers probably won't like this one, but I sense you're a little newer to the game and this may be a good read. Otherwise, Google "learning Ajax" and there are a bajillion resources.
Good luck!
To respond to your comment, you can set up a "router" script that takes input and runs a specific function in response. This "router" function looks at the $_GET[] superglobal for a parameter like "action" and then calls a corresponding function. If not action parameter is sent over, the router calls a default function.
Now for a little more detail. Your page script would have 3 basic parts: The router, the various action functions, and the page template function. The router just calls the appropriate function from the action functions and passes the output into the template function. Here are a few examples.
The user arrives on the page, index.php. No action is specified, so the router finds $_GET['action'] == '' and it calls default_action(). This returns a welcome message, status, whatever, and the router passes this output to the function that displays your page, output included.
Now the user clicks a link/button for updates and arrives at index.php?action=update. $_GET['action'] == 'update', so the router calls update_action(). The output goes on to the template function for display.
Does this help you envision how you might accomplish this?
Why use AJAX for dynamic web pages when you can do it only with php?
The main reason to bother with AJAX is User Experience (UX).
Now AJAX won't necessarily improve UX in every single instance so in a lot of places sticking with pure PHP is perfectly okay.
But imagine the case where you have a text field on the site and a link to vote on something. Kinda like this site. When you add AJAX your users won't loose the text they entered in the textfield when they decide to vote on the link! How incredibly useful!
So if you care about your user's experience it is a good idea to use AJAX in situations like that.
PHP creates and outputs the Content to the Client Browser as it's a Server-Side Language and that's what it was built for, so on a request your code will access database, files etc. and then output the constructed html/text to the client.
Ajax just gives the User a more Desktop like feel. For example deleting a record and instead of the entire page reloading just letting the one element disappear from say a list and letting the server know that the record is to be deleted. But Remember to let the User know when you are busy sending data to the server (With a progress bar in .gif format for example). As lot's of user feel that if nothing happens on the screen to notify them, that the application is frozen which means they will either reload the page or just try to click the button again.
But you will need to provide some sort of compatibility with browsers that have Javascript disable and thus cannot use your AJAX functions, just something to keep in mind.
AJAX stands for Asynchronus Javascript and XML, meaning that a page can get new data, without having to reload a page.
PHP cannot send data without reloading the whole page. A user has to press a button, to send data.
An example of AJAX is for example google suggestions or the tag suggestions on this website.
What is the best way to refresh the content of a var that is included? For example, I have this code:
<marquee>
<?php
include('note.php');
?>
</marquee>
This is great, as I can show on the page the contents of note.php. Say I change note.php but I don't want users refreshing to see the changes...is there any way to refresh the included file every 3 minutes for example?
To refresh only a portion of a page, you'll have to use some kind of Ajax Request : once the page has been sent to the browser, the server has done it's job, and cannot modify is anymore : the request of fetching a new portion of the page as to come from the browser.
You could do some Ajax requesting "by hand", it's not that hard ; but I'd rather suggest that you take a look at some of the great javascript frameworks that exists out there -- that might be helpful in the future, when adding more functionnalities to your application.
For instance :
With prototype, you can use Ajax.PeriodicalUpdater
Or, with jQuery, you could use something based on $.load
Only by using an ajax like call.. take a look at prototype or jquery for decent JS libraries to help with this..
Unless you just want to put some javascript in to refresh the page every three minutes, you'll need to look into another technology, namely AJAX. As far as I know, PHP can not do this alone.