I have yepnope to dynamically load css and js files. My yepnode calls on a specific event (button-click for eg:).
When I call for the very first time (js, css) - it loads file - I can see css properly done.
However, when the event is triggered second time which calls yepnope again - it just fails to download css again (or does not even use the older one).
Js works fine second time too when called. But css does not work.
However when I call injectcss in the callback of the js call, it injects again forcefully but it defeats the entire purpose of the speed.
Thanks.
Related
I'm adding a script tag to a web page once it's fully loaded in a WebEngineView, but it's silently failing somehow.
I inject the script by invoking webview.runJavaScript with this code:
var s = document.createElement('script');
s.src = "qrc:/jquery-2.1.4.min.js";
document.body.appendChild(s);
That's perfectly standard and to a certain extent it works as expected, i.e., if I view the html source of the page, the script tag has indeed been appended to the body.
The problem is that the script isn't being downloaded, or isn't being evaluated, or something. All I know is in the above example the jQuery functions aren't available. If I load a small JavaScript test file with one global variable, that variable's not available either. Changing the url to http instead of qrc and pointing it to a web server makes no difference.
Injecting an img tag works fine; the image is loaded and displayed.
But JavaScript is broken somehow. Does anyone know how to fix this?
The problem had to do with the asynchronous nature of QML and JavaScript.
I was inserting a script tag to inject jQuery, and then I was calling a function to de-conflict my inserted version of jQuery from whatever version of jQuery might already be in the original page.
But I believe the webview had not finished parsing the inserted jQuery library before my de-conflicting function was called, so it failed. (I'm not very experienced with browser programming or I might have suspected this from the beginning.)
The solution was to insert a script tag with a small bit of JavaScript that inserts jQuery and then sets a timeout to wait 200ms before calling the de-conflict function. Like so:
function insertAuhJQuery(){
var s = document.createElement("script");
s.src = "qrc:/jquery-2.1.4.min.js";
document.body.appendChild(s);
window.setTimeout(deConflictJQuery, 200);
}
function deConflictJQuery(){
auh = {};
auh.$ = jQuery.noConflict(true);
}
insertAuhJQuery()
That works reliably and is acceptable for my purpose.
Struggling here with what would otherwise be a simple $( document ).ready().
Not sure what I'm doing wrong.
Materialize needs jquery components to be initialized on DOM ready. Finding a way to initialize components on all views is surprisingly tricky.
Here is the online DEMO
From reading the docs: this should initialize everything the sub-templates require:
Template.layout.rendered = function(){
$('ul.tabs').tabs()
}
}
However, this only works on a hard page refresh, and not with links routing the views.
So instead you would have to initialize on each template that element will be used
Template.x.rendered ...
Template.y.rendered ...
Here is the github code
BTW We've tried iron-router events:
onRun
onBeforeAction
onAfterAction
All of these seem to happen before the route's template content is present. I noticed that onBeforeAction required a call to this.next() to go on, I even tried looking for the DOM content after the next call.
I also tried rewriting our routes like this:
Router.route('someRoute', function() {
this.render('someRoute');
// look for DOM content, still not found
});
Just to be clear, the reason this is happening is because your layout is only firing the rendered hook once. When you switch routes the layout template will not be rerendered, only the templates in the yield region will be. The previous template in that region gets destroyed and the next one rerendered. This means you have to run $('ul.tabs').tabs() again for that Template as the DOM elements it contains are rerendered.
Putting that code in the rendered function of the template that uses it works because that rendered hook gets run every time that particular template gets rendered again.
A way you could get around this could be to create a Template specifically for your tabs, like a control in a way, that calls $('ul.tabs').tabs() in its own rendered function. You could then put this control on a template that needed it and pass the required arguments, like number of tabs and content for each tab etc. It's a bit of work though, and I'd only consider it if I had a really large number of templates that used the tab control.
I'm using meteor & IronRouter, and trying to do some javascript-driven animations when the template is ready/rendered.
However, the IR hook events don't seem to fire when they should.
onBeforeAction and onAfterAction only seem to fire before the new page is rendered.
So there is no updated DOM to animate.
I also tried overriding the action, calling render myself, and then animating.
however, the DOM is still not updated... even using Meteor.defer
action: ->
this.render() # works ok
Meteor.defer ->
Template.SceneView.animateScene()
This was still getting called while the old template was present. I guess since Meteor is still updating async-ly, and so defer() didn't really defer...
So a hack around this is to call the animate function from the template itself, and then also use Meteor.defer to call the animation, so the DOM is updated.
The Blaze rendered() hook only fires once on template creation.
Separately there are some new ui_hooks in Blaze, but these seem to be before insert or deletes happen. I guess I could use this and take over the whole DOM manipulation but that seems like overkill for just playing some animations when a page is ready...
https://github.com/percolatestudio/transition-helper/blob/master/transition-helper.js
UPDATE. I found out about the afterFlush event
So it seems that having reactive templates, somehow makes defer timing not work.
Instead if I use the following, the DOM is all updated in time for the animation trigger.
action: ->
this.render()
Deps.afterFlush ->
Template.SceneView.animateScene()
You could also use plain css, if you have a package like animate.css in your app (http://daneden.github.io/animate.css/)
If you have this class animated bounceIn on the div or element thats at the top of your template it will also display an animation when the template comes into view.
Using jquery, I am swapping some content in a web page by use of jquery's .load() function. I want to trigger an event immediately once the content has actually been loaded, but not before and not after. I'm up for any graceful solution! Why? In this instance, I'm doing the old "fade out, swap content, fade in" approach. My problem? I want to fade back in AS SOON AS the new content is loaded.
Caveats:
Using a callback function as in $('#object').load(url, callback) triggers as soon as .load() function successfully executes (before the content is actually loaded). Useless here.
Using a timed delay for fading back in is not a graceful solution. Very "clunky", especially for those with faster Internet connectivity.
JavaScript's onload event trigger does not work, as the element that .load() is altering has already loaded into the HTML DOM.
jquery's .ready() function also does not work, as the actual element is already loaded.
I do not want to create an onload or .ready() sub-container element, because that's a workaround for what I'm actually trying, though it might be as graceful or more.
How can I fire a function when (and only when) the new .load() content is finally loaded, just like JavaScript's onload event does? Thanks much.
EDIT As it turns out, the jquery .load() function is working flawlessly, and I'm approaching this wrong.
Once the .load() function completes successfully, it calls any "callback" function included by the programmer, just like any other jquery function that accepts a callback as one of its "arguments".
The .load() function is complete once it either errors or successfully begins the HTML replacement and loading of new content, but that is IT! The content will then take however long it takes to load, but your .load call is already complete before that. Therefore, expecting the callback to run after the .load content has loaded will only disappoint you. ;)
I hope others can learn from this just as I did, including those who thought what I thought was the case. Proof: as stated in the jquery ajax .load page, the callback is executed when the request completes, not when the load completes. Eureka. Whoops. /EDIT
Try using a different method rather than load(), I would suggesting using get(). Something like this may be more useful to you...
var jqxhr = jQuery.get(url,vars);
jqxhr.success(function(data){
# This will only be called once the remote content has been loaded in
# The data will then be stored in the data param and can be used within your site
});
jqxhr.error(function(data){
# Something went wrong, never mind lets just handle it gracefully below...
});
I hope this is a solution to your problem!
For more information see http://api.jquery.com/jQuery.get/
I have quickly created this function below that may be of help to you... its not refined!
jQuery.fn.loadNewData = function() {
var object = jQuery(this);
var jqxhr = jQuery.get(arguments[0]);
// check for success
jqxhr.success(function(data) {
// load the data in
object.html(data);
});
jqxhr.error(function(){
alert('Failed to load data');
});
}
Using this you can call how similarly to how you would call the load() function.
jQuery('#object').loadNewData(url);
I think you might be misinterpreting what you are seeing. Depending on the browser you are using you won't see the new elements in the browser if you pop up an alert in the callback because it won't rerender the DOM until you cede control back to the browser. That doesn't mean you can't grab the new elements from the DOM and start fading them in. Take the following jsfiddle: http://jsfiddle.net/ttb55/8/ in Chrome it will show the first div when the second alert is up, then fade in the second div. In IE it won't show the first div when the second alert is up, this is the state I think you are in after load during the callback, but it still works once you hit ok because everything was in the DOM as promised.
Upon reading the jQuery docs pages for jQuery.get() and jQuery.load(), the callback argument is quoted as the following:
"A callback function that is executed if the request succeeds."
Let me stress the terms "request" and "succeeds". The request may succeed, but that does not mean that the content is loaded. Same problem as .load() — the functions aren't built the way I was thinking.
If I want to trigger an event once the new content finally loads, I'll need to take a different approach.
I could use the JS onload event, and trigger it by completely replacing an HTML element (having the replaced code contain an onload property). EDIT: Note that using HTML iframe elements is pretty awful, primitive, and "clunky". I just need to find a better way to trigger a function as soon as loading the new content finishes.
Also, I could use jQuery to check the .ready() state of new content, but ("AFAIK" / as far as I know) that will only work if the checked content is a new HTML element, not a preexisting HTML element whose interior content is changed. The jQuery .ready() status of any preexisting element will (AFAIK) already be shown as "ready" despite if new content is loading. Perhaps I am wrong about this, and I would like to be corrected if so.
Unless otherwise notified, this answer will be marked as the correct one. The original question was mistaken that .load() was all I needed. Cheers!
Is it mandatory to write $(document).ready(function () {... }) every time ?
Can't we do it without this line?
The reason for placing your code inside this function is that it will get called once the DOM has loaded - meaning that all the elements are accessible. Calling jQuery selectors without this function means that the elements have not necessarily been loaded into the DOM and might not be accessible (and you'll see weird results or nothing at all from your code).
So in essense, yes, it is necessary.
$(document).ready makes sure your code runs when the document is ready (i.e. fully loaded). If you don't need to interact with the document, you don't need this. If you put your Javascript at the end of the document, you probably don't need it either. You should put your code into a function () { } though to namespace it either way.
$(document).ready means the code inside this box will be executed once the all document is ready (loaded). It is considered as safe programming but not mandatory.
For example you call a function in script tag do_something(); and this function is in a js file which is not loaded yet then you will get javascript error.
If you put function like this
$(document).ready(function () {
do_something();
});
you are making sure that when function get called all js files will be there to server.
If you don't use that line, and just include the javascript in your body, it will execute as soon as it's loaded. If it's trying to act on DOM elements that have not yet loaded, unpredictable results will occur.... better to be safe than sorry.
jQuery's ready() function is run after the page's content is loaded. This is relatively equivalent to using <body onload="function1();function2();">
If you want to call multiple functions when the page is done loading, you can do the following:
$(document).ready(function() {
function1();
function2();
});
In order to use javascript, you must call it somewhere. This can be in body "onload", jQuery's ready() function, or an event, like a mouse click event.
No you don't always have to do this. You only use it if you want to make sure whatever is inside the ready function loads before the page is displayed in the browser. If you do not care to load the script before page load, then you can just put the script at the end of the page before the closing body tag.
Also As a shortcut to $(document).ready(function () you can do $(function()