emberjs event for when model changes - events

I have an emberjs app that is structured very much like the sample here:
https://github.com/tildeio/bloggr-client
The question I have is that when the user clicks on a 'post' on the left, is there any event I can subscribe to in the post view/route/controller that i can tap into? A javascript library I'm using (gridster) requires some javascript to be run as the user switches from post to post. I've tried using didInsertElement but that doesn't seem to fire (using 1.0.5)

You can observe the PostController's content property. This can be done from anywhere that has access to the PostController. For example, from PostView:
App.PostView = Ember.View.extend({
templateName: 'post',
contentDidChange: function() {
console.log('content changed to: ', this.get('controller.content'));
}.observes('controller.content')
})

Related

auto save to db in ruby camping web app

I need help with the form submission and saving to db in my ruby camping web app.
The app itself is a quality assurance app. Users fill in forms for any errors detected during the quality check. The problem is that the check can take for a couple of hours or in extreme cases even more. During that time, in order to save the data, users have to submit the form several times. Currently I've set it up so that the users submit the form and are immediately redirected back to the form.
How would I go about to enable some sort of autosaving, let's say every 10 minutes or upon each change to the form so users don't have to do it manually.
This is quite difficult for me because I'm not a programmer per say, butI learn as go alogn to optimize my processes.
I've been reading about ajax and jquery but I'd really appreciate if someone could point me in the right direction since I don't know where to start and camping examples are rather scarce.
EDIT
Some additional infos:
I've successfully implemented jQuery to my camping app and I can manipulate html elements, but AJAX doesn't work. Firebug console doesn't return any errors.
Here are my assumptions:
If the form can be successfully submitted manually I don't have to change anything in my controller or view in order for AJAX to work, right?
The url passed to AJAX doesn't have to include the object id for which I want to submitt the form, right? I'm passing the '/edit' url and the full url to the relevant object is for example '/edit/5'.
Here is the code from the html head:
script :type => 'text/javascript' do "
$(document).ready(function() {
$('#np').change(function() {
$('#add_form').submit(function() {
$.ajax({
type: 'POST',
url: '/edit',
data: $('#add_form').serialize(),
});
});
});
$('#search_indiv_form').click(function(){
$('#search_indiv_form_toggle').toggle(700);
});
});"
end
Are there any errors in my ajax code to prevent the form being submitted?
thank you.
regards,
seba

What is the right away to update a panel using AJAX?

In MVC4 applications, I would like to update a panel using AJAX but using jQuery methods instead using AjaxExtensions from MVC.
But my problem is the updatePanelId.
I've seen several people use this to update it when has success:
success: function (response) {
var $target = $("#target");
var $newHtml = response;
$target.replaceWith($newHtml);
}
But when I do this, it forces me to use in every partial view that includes the id="target" at the root level of my razor view, and I guess that's not a good practice; I said this because I've realized when I use AjaxExtensions it doesn't happens, replace the update and it does not remove the panelId. But using jQuery it does.
Any idea to port the AjaxExtensions feature to jQuery?
You can use just:
$("#target").html(response); // it will just update content of the $("#target") container
Use jQuery's .load function. This will load the contents of the URL you specify into the target element. You can optionally specify a selector after the URL in load to only grab part of the target page.
$(function() {
$("#target").load("/MyURL");
});
JavaScript same origin policy applies to this.

how to access the id of div which is loaded through ajax

I have button with id = new which loads the new page
$("#new").click(function(){
$('#message_area').load('new.php');
});
There is a button in new.php which sends message to database. But i have a problem with it , it only works for first time when page loads if i navigate to some other links via ajax and again load new.php using above code then send button in new.php does not work i have to refresh the page then it works. I think its because the send button in new.php is added after DOM is created for first time .
Please help Thanks in advance ..
You will need to post more details of your markup for a more accurate answer, but the general idea is to use event delegation. Bind the event handler to an ancestor of the button that does not get removed from the DOM. For example:
$("#message_area").on("click", "#yourButton", function() {
//Do stuff
});
This works because DOM events bubble up the tree, through all of an elements ancestors. Here you are simply capturing the event higher up the tree and checking if it originated from something you are interested in (#yourButton).
See jQuery .on for more. Note that if you're using a version of jQuery below 1.7, you will need to use delegate instead.
//jquery >= v1.7
$("body").on('click', '#new', function(){
$('#message_area').load('new.php');
});
//jquery < v1.7
$("#new").live('click',function(){
$('#message_area').load('new.php');
});
$("#new").live("click", function(){
$('#message_area').load('new.php');
});
just realized this was deprecated-- should be using on instead.. my bad.
To manage dynamically created elements like this, you need to use .on() (jQuery 1.7 and above) or .delegate() (jQuery 1.4.3 and above) to assign the events. Seems everyone has beaten me to the code, but I'll post this for the links to the functions.

JQuery Mobile and JSONP

I have my jquery mobile app pulling data from our mysql db using JSONP. The data is pulling fine, but the problem comes when I go back to the previous "page" in my app then click on a different option, it doubles the data on the next screen, and it will just keep stacking the data as many times as I do that. What am I missing?
The app doesn't look right in any browsers, but it looks fine in the ios simulator or appmobi simulator. I can post some code if needed, just know it won't look right in your browser.
Thank you for any help you can provide
$('#two').bind('pagecreate',function(event){
var img = getUrlVars()["st"];
var photo = $('#img');
$.ajax({
type: 'GET',
url: 'http://serverhidden/json/img.php?st='+img,
dataType: 'jsonp',
success: function(data) {
$.each(data, function(i,item){
var image = '<img class="stmap" src="images/states/lrg/'+item.img+' "/>';
photo.html(image);
});
},
error: function(e) {
//called if there is an error
//console.log(e.message);
}
});
});
Make sure you are not subscribing your event multiple times. It seems silly but is easy to do.
I would recommend you add logs to your JQM site so that you can see how many times your site is being updated.
You should also be aware that updating a JQMobile page often requires a call to a method to update content after a page is rendered. See here: jQuery Mobile rendering problems with content being added after the page is initialized
Hope those help.
So without any code from your project this is a shot in the dark but it seems like you populate a pseudo-page with information on pageshow with an .append() call. Instead of using .append(), use .html() as it will replace the information already present rather than add to it.
If each state has an individual page then you can bind to the pagecreate (or similar) event so the data will only be appended once rather than on each pageshow event.

How to "bookmark" page or content fetched using AJAX?

How to "bookmark" page or content fetched using AJAX?
It looks like it can be easy if we just add the details to the "anchor", and then, use the routing or even in PHP code or Ruby on Rails's route.rb, to catch that part, and then show the content or page accordingly? (show the whole page or partial content)
Then it can be very simple? It looks like that's how facebook does it. What are other good ways to do it?
Update: There is now the HTML5 History API (pushState, popState) which deprecates the HTML4 hashchange functionality. History.js provides cross-browser compatibility and an optional hashchange fallback for HTML4 browsers.
To store the history of a page, the most popular and full featured/supported way is using hashchanges. This means that say you go from yoursite/page.html#page1 to yoursite/page.html#page2 you can track that change, and because we are using hashes it can be picked up by bookmarks and back and forward buttons.
You can find a great way to bind to hash changes using the jQuery History project
http://www.balupton.com/projects/jquery-history
There is also a full featured AJAX extension for it, allowing you to easily integrate Ajax requests to your states/hashes to transform your website into a full featured Web 2.0 Application:
http://www.balupton.com/projects/jquery-ajaxy
They both provide great documentation on their demo pages to explain what is happening and what is going on.
Here is an example of using jQuery History (as taken from the demo site):
// Bind a handler for ALL hash/state changes
$.History.bind(function(state){
// Update the current element to indicate which state we are now on
$current.text('Our current state is: ['+state+']');
// Update the page"s title with our current state on the end
document.title = document_title + ' | ' + state;
});
// Bind a handler for state: apricots
$.History.bind('/apricots',function(state){
// Update Menu
updateMenu(state);
// Show apricots tab, hide the other tabs
$tabs.hide();
$apricots.stop(true,true).fadeIn(200);
});
And an example of jQuery Ajaxy (as taken from the demo site):
'page': {
selector: '.ajaxy-page',
matches: /^\/pages\/?/,
request: function(){
// Log what is happening
window.console.debug('$.Ajaxy.configure.Controllers.page.request', [this,arguments]);
// Adjust Menu
$menu.children('.active').removeClass('active');
// Hide Content
$content.stop(true,true).fadeOut(400);
// Return true
return true;
},
response: function(){
// Prepare
var Ajaxy = $.Ajaxy; var data = this.State.Response.data; var state = this.state;
// Log what is happening
window.console.debug('$.Ajaxy.configure.Controllers.page.response', [this,arguments], data, state);
// Adjust Menu
$menu.children(':has(a[href*="'+state+'"])').addClass('active').siblings('.active').removeClass('active');
// Show Content
var Action = this;
$content.html(data.content).fadeIn(400,function(){
Action.documentReady($content);
});
// Return true
return true;
And if you ever want to get the querystring params (so yoursite/page.html#page1?a.b=1&a.c=2) you can just use:
$.History.bind(function(state){
var params = state.queryStringToJSON(); // would give you back {a:{b:1,c:2}}
}
So check out those demo links to see them in action, and for all installation and usage details.
If you use jquery, you can do that in a simple manner. just use ajaxify plugin. it can manage bookmarking of ajax pages and many other things.
Check this, something may help you:
How to change URL from javascript: http://doet.habrahabr.ru/blog/15736/
How to pack the app state into url: http://habrahabr.ru/blogs/javascript/92505/
An approach description: http://habrahabr.ru/blogs/webstandards/92300/
Note: all articles are in Russian, so either Google Translate them, or just review the code and guess the details.
Take a look to the Single Page Interface Manifesto
I tried many packages. The jQuery History plugin seems to be most complete:
http://github.com/tkyk/jquery-history-plugin

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