I am working on an application using flutter and Mysql DB with PHP Laravel , I have the same post on two different pages (posts come from view in DB).
when I delete or add or edit (do CRUD functionality) that post on the first page the effect does not reflect on the other page in the application (inconsistency), so I must refresh the other page (call API) to show the effect in it.
I try to get all lists that contain posts and search on them to see if a post exists there and do they reflect on it, but there are 3 or 4 lists I need to check every time and this makes the process complex on RAM as a phone application. I also search for something like ajax on the web but I found nothing.
what I need is when I delete or edit the post on the first page this post is also deleted or edited on the second page without doing a refresh.
Related
I want to load a page from a different source like how the online flight ticket reservation sites are working. Meaning the data needs to be pulled from different systems and show it up in a single page.
I can do this by creating one file which can collects the data from different systems and merge it by the required sort order and show in the page. But if any one of the source systems works slow then the entire page needs to wait till all the results are received from various sources.
The Question is
Is it possible to show the content which is retrieved from various sources without any middle layer to manipulate data before display? Meaning the page will show the content when it receives from either of the sites at first and the page will reorder when it receives the content from other sites.
Advance thanks for your help.
The way i solved this issue by doing the below.
Created one aggregate layer, which makes the request (curl) to different systems (asynchronous)
Upon receiving response from one system (whichever comes first) have stores it in cache (memcache) and display the result in the page
Then when the response comes form the other system, aggregate the result with the previous results which is stores in cache and refresh the page again with the aggregated data
I know this is not a good solution, but since i don't have any better option and right now handling it like this.
I have an application where I use ajax to update the comments & Like count.
I am using Codeigniter page caching http://www.codeigniter.com/user_guide/general/caching.html
and set following code to recreate caching every 60 minutes
$this->output->cache(60);
Problem is when somebody enter a new comment, DB operation is happening (Because of Ajax call), But the Newly inserted comment disappears after the page refresh, because of the cached HTML page. How to handle caching and also dynamic content to change?
The main purpose of caching is to save server resources on page load (i.e. so the server doesn't need to fetch all the dynamic data every time its loaded).
It sounds like you are using the AJAX function to both submit the data but also modify the webpage on the client side simultaneously. When the user then refreshes the page, this will fetch the content back from the server, in this case the original cached content that was generated before the comment was made and is therefore operating exactly as it should.
If you have a true requirement for caching this page, you could consider deleting the cache, which would force it to be rebuilt on the next page load whenever a comment is made. Placing the following line of code in your controller (in the function that received the AJAX data) should do it:
$this->output->delete_cache('foo/bar');
I found the solution.
To delete a cache file you need to use the following function
$this->output->delete_cache('CONTROLLER/FUNCTION');
Note: No Slash before or after.
In my Case i was using custom routes in codeigniter. When user type example.com it is routed to example.com/CONTROLLER/FUNCTIONNAME and that too default landing page.
So i created a new function. Please refer here
I have sort of design problem with my site. Here's the introduction:
I have a simple, dynamic page which contains a videoplayer and next to it a bunch of videos to play. Under the videoplayer there's a comment section that is powered with jquery form plugin because naturally I don't want the page to refresh and reset the video if someone enters a comment while watching.
So, the page fetches the video ID to play via a $_GET variable and then gets another 10 or so video links based on the ID from MySQL database and plays the first one and lists the rest as links next to the player.
The comment system is simple. It fetches all the comments from MySQL table having the same ID as the video playing and lists them via the jquery form plugin mentioned before. Upon entering a new comment it adds the comment to the table again by targeting the same ID.
Since the ajax form plugin fetches the comments from external PHP files containing the comment showing/adding code - I have to use a $_SESSION variable to pass the info from the main page to those files.
And here's the problem:
Everything works as I expected when a client browses the page normally.. but when he decides to open another video to a new tab - the comment system breaks down.
So what happens is that I pass the video ID from the main page's $_GET variable to a $_SESSION variable and use it to let the external show/add-comments-PHP-files know which comments to show. This works fine when a client is using only one tab but when he opens another video in a new tab the $_SESSION variable of course updates to match the new tab's currently playing video's comments and since this variable is same in both tabs - the original tab now points wrongly to the new tab's comments.
So.. to hopefully clarify a bit:
browser tab 1:
$_SESSION['now_playing'] = video 1
[..client opens another video into a 2nd tab]
browser tab 2:
$_SESSION['now_playing'] = video 2
..and from this point on the tab 1's comments are of course the same
as tab 2's.
Would there be any tricks to start a new session upon a new tab creation or something like that? I'm rather new to all this so there might be obviously silly involved.. any pointers how to get this fixed would be greatly appreciated - even if it's a better way to implement the commenting - adding comments without a page refresh is a must tho.
Regards, kitsu
You are hitting the classic problem that the Session data is controlled by a cookie, and is therefore per browser not per screen.
One approach is to have a hidden field on the screen. When handling the get to create the screen, set this to a unique value, and use that value as a key into the session data.
Then pass the value back with the ajax requests - so each screen's requests are handled with a different part of the session data.
The scenario (all happening within the administration area/backend):
From the listing page, the user clicks a link to view an article (on the backend).
From the article view page, the user clicks a link to edit that article.
In the article edit page, form is submitted to the current uri.
If validation succeeds or user cancels, user is redirected to the article view page.
From the article view page, the user click a 'back' link to return to the listing page.
List <--> View <--> Edit
Right now, I'm only able to track referring url from a previous page. In the edit form, I'm using a hidden field to maintain referral to the view page, lest it be changed during failed form POST submission to itself and user remains in the edit page.
Problem is that when the user returns to the view page from edit, the 'back' link to the listing page is now linked to the edit page.
FYI,
The listing page url is dynamic as the user should return to the listing on the same page and sort order (stored in query strings); therefore a fixed url is out of the question.
In the past, I've tried using sessions (e.g. SESSION['view_to_list_ref'] SESSION['edit_to_view_ref']), but it messed up with multiple tabs.
I could transition between view/edit via ajax, but I'm hoping to keep the app simple and ajaxless at this point of time.
I'm using PHP + Kohana 3.2 Framework
The only solution I can think of is to have the list page url encoded and appended to the 'view article' link via query string. This way, the location of the listing page is preserved even while in the edit page; as the referring url back to view page would also contain the listing page url in the query string. However I don't really like the idea of 'dirtying' the url with long parameter values (encoded or not).
I'm really hoping there is a more elegant solution to this problem of generally tracking multiple levels of page referrals; not just specifically to solving the scenario I've mentioned.
EDIT: Oh and the solution should be able to support multiple tabs performing the same scenario.
You could track the pages by using a unique identifying code in a PHP session, a temporary variable, and using a temporary database table that tracks page loads by these temporary values.
The database structure might be:
+-------------+-------------------+---------------------+
| Unique ID | Page Referral | Time of page load |
+-------------+-------------------+---------------------+
Tracking time of page load would allow you to selectively wipe loads older than X minutes, and keep the table relatively small.
Anyway, this would allow you to keep as many levels as you'd like, and if you wanted to add an auto incrementing counter field, or your own counter field, you could even keep a simple to use number system that tracks page loads, though I believe the time of page load would suffice for that scenario.
I'm working for a client who asks me to prepare a module for its website (written using Yii) with the following features:
It shows 3 elements from a mysql_result, starting from offset=0.
The user can click on any of them to mark them as "read". That makes the desired item to disappear and to appear what would be the following item. That is, if you are showing items 3 4 5 and you click on 4, that item would disappear and appear the number 6, meaning the result would be 3 5 6.
The elements being shown are partial views and the button that "deletes" the item is a widget within each partial view.
The user can move through the list of items using some << and >> arrows to go back and forth the result.
One of the options the client gave to me was to show a list of pages ( 1 | 2 | 3 | 4... and so), but deleting items means the number of pages will decrease at some time in the future, plus if the amount is pretty big, I would need something more flexible such as only showing the current and other 4 pages at most. Another option is to keep the << and >> arrows.
I've tried to convince the client that pagination and a "live list" is a pretty bad idea, but he rejected the idea to limit the visualization to only the first 3 items (keeping in mind that eventually you will delete them and thus will be able to see the following items).
I'm developing it using Yii, MySQL and jQuery, and I'm not able to use CPagination because of this living list. I'm not asking the code, just some guidelines because I got lost the third time I tried doing it.
Some basics about the system:
I got a controller which loads the first 3 items of this module.
I got some actions in this controller that fetches the next item within a page (which may not be the same of the current object, though. One of my problems resides here), and the full page.
Each item is able to mark itself as "read", which will make the item not appearing the next time you fetch some results.
Every 1 second I check for items that have been marked as read, remove from DOM and append some new items using the action I defined in the second bullet.
Every time the user hits the << or >>, I reload the previous/next page (That would not be a problem apparently. If you're in the last page and there aren't more items to add, you just remain there. However if you empty the page, I don't have any method to detect that and scroll one page back).
As you may see, this headache would be easier without the pagination buttons, but the client obligues me to put them. What would you do guys? Thanks in advance
EDIT: The client decided to get the results in a random flavor. There is no more pagination, so the problem has disappeared. The #thaddeusmt answer may not have helped me really much, but I'll give it as valid, as it might be plenty useful for other people with similar problems than mine. Cheers
It seems to me like the CGridView or CListView should basically do this automatically. They support AJAX updating/paging out-of-the-box.
I assume that you have an AJAX action that like "actionMarkRead()" which you are calling when the user clicks. I assume that this sets some database field somewhere saying that the user has "Read" that item. To make this work with the CListView, just make sure that the CDataProvider has a condition which checks that "read" field (might have to JOIN a table, I don't know what your DB looks like). Then, when the list reloads via AJAX, it will have the correct # of pages to represent the smaller number of pages the CDataProvier query is returning.
I just tested this and it works!
The way I tested it is I set up a CGridView with 'ajaxUpdate'=>true,. Then in my CDataProvider I set 'pagination'=>1 to make it easy to test. Then I used the default AJAX actionDelete in my Controller to delete the items. Every time I deleted an item via that AJAX action link in the CGridView, the grid refreshed via AJAX and page count shrunk by 1. Seems to work like a charm!
Cheers and good luck!