My main problem is due to scripts running before DOM is loaded and i can't use document.ready event. For more details read further
I am making a ad serving app. I have made a small code snippet which will be given to the publisher to add on their website to load our ads. A specimen of the same is as follows:
<div class="my-widget" data-widgetId="1" data-page-url="http://foo.bar/" ></div>
<script src="http://myadserver.exp/js/widget.js"></script>
The HTML div is where ads are to be displayed by the script just below it.
This script also contains methods to verify add and fill ads in that div.
var adDiv = document.getElementsByClassName('my-widget')[0];
insertScriptWithSouce('http://myadserver.exp/serve.php?id=' + adDiv.dataset.widgetId);
function fillAds(htmlFromserver) {
adDiv.innerHTML = htmlFromServer;
}
This is only a example to understand the scenario
Now my problem is if a publisher adds more than one widget on the same page
That code would look like
<div class="my-widget" data-widgetId="1" data-page-url="http://foo.bar/" ></div>
<script src="http://myadserver.exp/js/widget.js"></script>
<div class="my-widget" data-widgetId="2" data-page-url="http://foo.bar/" ></div>
<script src="http://myadserver.exp/js/widget.js"></script>
without any of his own html
Now the ad from the second widget get placed in the div of first widget and the second widget remains empty
I have also tried loops for many classes but when each script runs it does not know that there is another widget below it as it is not yet loaded in the DOM
Note: I can not use ids and jQuery as its forbidden by seniors
I also cant use document.ready event as if document fails to load then my ads will not be served
Instead of having multiple script blocks, just have one script reference that loops through the ad container divs on the page.
function fillAd(htmlFromServer, widgetId) {
var adDivQuery = document.querySelectorAll('[data-widgetId="' + widgetId + '"]');
if (adDivQuery.length > 0) {
adDivQuery[0].innerHTML = htmlFromServer;
}
}
var adDivs = document.getElementsByClassName('my-widget');
for (var i=0, il=adDivs.length; i<il; i++) {
insertScriptWithSource('http://myadserver.exp/serve.php?id=' + adDivs[i].dataset.widgetId);
}
In this scenario the script inserted by the insertScriptWithSource() function will pass a second argument into your fillAd() function with the widget ID that was initially passed to it.
Got nothing as a solution but still got the best way around so I thought it might help someone else
This javascript can be used for solution
var adDiv = document.querySelectorAll('my-widget:not([id])');
adDiv = adDiv[0];
adDiv.id = 'my-id' + (Math.random() * 100).toFixed(0);
insertScriptWithSouce('http://myadserver.exp/serve.php?id=' + adDiv.dataset.widgetId + '&origId=' + adDiv.id);
function fillAds(htmlFromserver, idSentFromHere) {
adDiv = document.getElementById(idSentFromHere);
adDiv.innerHTML = htmlFromServer;
}
Related
I have this function to print a DIV.
Whenever the page is loaded and I click in a "Print" link I have, the DIV is shown to be printed without CSS.
If I close Chrome's print visualization page and click in the "Print" link again, the DIV has CSS applied.
Any ideas why?
Javascript
function printDiv(divId) {
var printDivCSSpre =
'<link href="/static/assets/vendor/sb-admin-2-1.0.7/bower_components/bootstrap/dist/css/bootstrap.min.css" rel="stylesheet">' +
'<link href="/static/assets/vendor/sb-admin-2-1.0.7/dist/css/sb-admin-2.css" rel="stylesheet">' +
'<div style="width:1000px; padding-right:20px;">';
var printDivCSSpost = '</div>';
$('body').append('<iframe id="print_frame" name="print_frame" width="0" height="0" frameborder="0" src="about:blank"></iframe>');
$("link").clone().appendTo($("#print_frame").contents().find("head"));
window.frames["print_frame"].document.body.innerHTML =
printDivCSSpre + document.getElementById(divId).innerHTML + printDivCSSpost;
window.frames["print_frame"].window.focus();
var windowInstance = window.frames["print_frame"].window;
windowInstance.print();
}
HTML
<a id="print" href="#">
<i class="fa fa-print"></i> Print
</a>
<script>
$('#print').click(function () {
printDiv('report')
})
</script>
<div id="report" class="report">
<p># Generated Table#</p>
</div>
First click:
http://imgur.com/a/Go81Y
Closing the print preview page and clicking again in print
http://imgur.com/a/SCxJF
This happens because when you call your printDiv() function, css is also written using inner HTML and in this scenario CSS is not applied during first click because you wrote CSS to the elements even when they do not exist inside DIV.
The function to work as desired has to write DIV contents first and then CSS should be applied. I would say write css after contents of DIV or load on top of your HTML page and just write DIV contents.
Hope that helps.
Every thing is right just change the sequence. In browser debugger on first click it didn't show 'print_frame' in sources section while in second click it does (I am using chrome devtool).
So load in memory frame with css attributes during onload:
var windowInstance;
$(function(){
$('body').append('<iframe id="print_frame" name="print_frame" width="0" height="0" frameborder="0" src="about:blank"></iframe>');
$("link").clone().appendTo($("#print_frame").contents().find("head"));
windowInstance = window.frames["print_frame"].window;
});
and onClick just append html
$('#print').click(function () {
var divId = 'report';
var printDivCSSpre ='<div id="printReportDiv" style="width:1000px; padding-right:20px;">';
var printDivCSSpost = '</div>';
window.frames["print_frame"].document.body.innerHTML = printDivCSSpre + document.getElementById(divId).innerHTML + printDivCSSpost;
window.frames["print_frame"].window.focus();
windowInstance.print();
});
updated jsfiddle
Try this one. The problem mainly arises because the css has not been applied to the page when the print command is initiated. setTimeout is one way to solve it as others have mentioned but it is really not possible to predict how much delay you will need. Slow internet connections will require high delays before you fire the print statement. The following code, however, only fires the print event after the css has been properly applied to the iframe.
$('#print').click(function () {
if($("#print_frame").length == 0) {
$('#report').after('<iframe id="print_frame" name="print_frame" width="0" height="0" frameborder="0" src="about:blank"></iframe>');
}
var $head = $("#print_frame").contents().find("head");
// for now for ease I will just empty head
// ideally you would want to check if this is not empty
// append css only if empty
$head.empty();
$.ajax({
url : "https://dl.dropboxusercontent.com/u/7760475/reports.css",
dataType: "text",
success : function (reports) {
// grab css and apply its content to the iframe document
$head.append('<style>'+reports+'</style>');
$.ajax({
url : "https://dl.dropboxusercontent.com/u/7760475/bootstrap.css",
dataType: "text",
success : function (bootstrap) {
// grab another css and apply its content to the iframe document
// there may be better ways to load both css files at once but this works fine too
$head.append('<style>'+bootstrap+'</style>');
// css has been applied
// clone your div and print
var $body = $("#print_frame").contents().find('body');
// empty for ease
// but later append content only if empty
$body.empty();
$("#report").clone().appendTo($body);
$('#print_frame').get(0).contentWindow.print();
}
});
}
});
});
Use inline CSS instead.
Reason: When we PRINT or save as PDF if fails to fetch external css Files, So we have to use Inline css.
edited your file please see: jsfiddle.net/ytzcwykz/18/
As other people mentioned it is hard to see your problem without seeing the working example of a problem, but just guessing from the code:
Browser is not able to load the CSS before your print() call.
Browser is not able to render the CSS before your print() call.
Keeping that in mind changing your JS function that way might do the trick
function printDiv(divId) {
$("link").clone().appendTo($("#print_frame").contents().find("head"));
window.frames["print_frame"].document.body.innerHTML =
printDivCSSpre + document.getElementById(divId).innerHTML + printDivCSSpost;
window.frames["print_frame"].window.focus();
var windowInstance = window.frames["print_frame"].window;
setTimeout(function() {
windowInstance.print();
}, 0);
}
The idea behind this function is to let browser execute it's code after we added changed the HTML/CSS code in the window - see Why is setTimeout(fn, 0) sometimes useful?
WARNING: this approach is not tested for your particular problem, and it might also not work because we escape/leave the mouse-click call-stack, calling print() method might be not possible out of user-interaction stack.
UPDATE: after looking in the posted jsfiddle - my assumption was correct, the browser needs some time to load and render the CSS, that is why calling the print() right after changing iframe contents doesn't give the desired result. There are 3.5 ways to solve that:
Use events to identify when iframe's document and window has finished loading and rendering. I tried two approaches, and failed so far, need to read docs more carefully about when document and window are behiving during the loading sequence:
we can do that from outside of iframe, i.e. listen to events of iframe element and it's children
we can do that from inside of iframe, i.e. add little javascript snippet inside which will send a message to the parent window when loading is done.
Consider forming the print result different, how about print style-sheets? I.e. add one more style sheet with print-media query to the parent doc and just call print on it?
Consider forming an iframe which is already loaded and ready to be printed, but replace just the table contents inside it.
As others mentioned, The problem here is that the CSS files used are external resources and browser takes time to download and cache it locally. Once it is cached, it would serve faster and that's why it works fine from the second click.
As Anton mentioned, setTimeout is the key here! You may probably increase the timeout seconds to make that work. I tried setting it to 500ms and that worked,
setTimeout(function(){windowInstance.print();},500);
I'm implementing (through pure JavaScript) something like facebook's message loading. Meaning that if you scroll to the end of the page, new (HTML) content is loaded and added to the end of the page. I get this extra content through Ajax. But when I add this (HTML) to the page, it could mean the page has to load extra images. Is there a way I can figure out when the page has finished loading everything, so including all the new images?
You can add the load event (https://developer.mozilla.org/en-US/docs/Web/Events/load) to the appended elements:
function LOADER_FUNCTION(e) {
console.log("LOADED", e.target);
}
var element = document.querySelector('#parent');
for(i=0; i<element.childNodes.length; i++) {
element.childNodes[i].addEventListener('load', LOADER_FUNCTION);
}
This will call the LOADER_FUNCTION function when the content within that element is ready. Oddly this doesn't seem to work when attached to the parent.
Edit:
Here is a working example. Although this example is not using Ajax (mainly due to CORS issues) it should work under the same conditions. I've used innerHTML to set my DOM in order to demonstrate that this event is not limited to createElement -> appendChild:
(function(){
// This Code Runs after DOMContentLoaded
var element = document.getElementById('parent');
function LOADER_FUNCTION(e) {
document.querySelector('.status').innerText = ("LOADED " + e.target.tagName);
console.log("LOADED", e.target);
}
element.innerHTML = "<img src='http://i.imgur.com/OfSN9oH.jpg'>";
for(i=0; i<element.childNodes.length; i++){
// Attach new event handler
element.childNodes[i].addEventListener('load', LOADER_FUNCTION);
}
})()
<div class='status'></div>
<div id="parent"></div>
Edit 2:
For nested children in append/innerHTML use element.querySelectorAll('*');
https://jsfiddle.net/bckpL9k6/1/
i have a problem with my page.
When i click on a link on my page, it will load a external html inside a div in the page. the div with the id="div1". (AJAX)
It works perfect.
the external html-page which has been loaded includes a div with the id="rex".
My Problem is:
i have a script, which must add content in the div (with the id="rex")
i wrote the script in the external file, but it doesn't run.
probably i must write my script in the page and not in the external html-file.
here the script Number 3:
$('#rex').ready(function() {
var url="genredetail.php";
var activitydetail = sessionStorage.activitydetail;
$.getJSON(url,function(json){
$.each(json.genredetail,function(i,item){
if(item.name == activitydetail){
$('<p class="excerpt">' + item.beschreibung3 + '</p>').appendTo('#rex');
}
});
});
});
This script must run when the external file (with the div id="rex") has been loaded. But it doesn't :-(
What can i do? Is the problem that the script runs before the page get the <div id="rex">?
Thanks in advance, and sorry my bad english :-S
A picture for more clearness
the script number 1 makes the link.
when i click on a link, the script number 2, let the site load in the div1.
The script number 3 must fill the div="rex" with informations. but it doesn't run.
try onload
$('div').on("load","#rex",function() {
do something
});
Try using setInterval, so it check the element rex every 0.5 s
var myInterval = setInterval(function(){
if ($("#rex").length)
{
var url="genredetail.php";
var activitydetail = sessionStorage.activitydetail;
$.getJSON(url,function(json){
$.each(json.genredetail,function(i,item){
if(item.name == activitydetail){
$('<p class="excerpt">' + item.beschreibung3 + '</p>').appendTo('#rex');
clearInterval(myInterval);
}
}, 500);
You need to reload the script if it is already loaded. As you said you are loading the external html inside a div, does it include the external js file you are using? if not please include it.
I have a report generated by Oracle Apex (A UI tool operating against the Oracle database). I have customized it to have a hyperlink on each record, which when clicked opens a detail report in an iframe right under the current record. This, I am doing by using the Javascript insertRow method on the html table element (Condensed Javascript code below. Oracle APEX allows use of JS/Jquery)
var pTable= html_CascadeUpTill(t,'TABLE');
var myNewRow = pTable.insertRow(pTR.rowIndex+1);
var myNewCell = myNewRow.insertCell(0);
myNewCell.innerHTML = '<iframe src="detail report url" height="0"></iframe>';
In order to resize the height of the iFrame that is different for different detail records, I have the following code in the document).ready(function() of the page
$('iframe').load(function()
{
setTimeout(iResize, 1000);
}
function iResize()
{
// Iterate through all iframes in the page.
for (var i = 0, j = iFrames.length; i < j; i++)
{
var y=(iFrames[i].contentWindow || iFrames[i].contentDocument);
if (y.document)y=y.document;
var docHt = getDocHeight(y);
if (docHt) iFrames[i].height = docHt + "px";
}
}
);
Without the setTimeout call to iResize function, the iframe resize is not happening. But this setTimeout is adding a delay in the resized iframe to appear which I want to avoid. Is there a way to do this? All the related posts/articles I have seen online deal with iframes that are built into the page but not generated on-the-fly as in my case.
Let me know if you need more information. Please help. Thank you.
You should consider putting the details in a <div> block, then showing or hiding the <div> with JQuery. You can set dimensions for your block with CSS, or just let the content flow normally inside of the block. Sounds like a much simpler way to achieve the same effect.
The issue is that if you perform the resize too soon it will get the dimensions of the child document before it has been fully rendered, hence the use of a timer.
If your detail reports are other APEX pages that you control, then you could call the iResize function from the "Execute when page loads" section of the detail page:
parent.iResize();
That seems to work for me.
It sounds to me like the iframes don't even exist when the page first loads.
Instead of calling the iResize function on page load and then every second you could place the call to iResize in the code that creates the iframe.
We're using OpenX to serve ads on a number of sites. If the OpenX server has problems, however, it blocks page loads on these sites. I'd rather have the sites fail gracefully, i.e. load the pages without the ads and fill them in when they become available.
We're using OpenX's single page call, and we're giving divs explicit size in CSS so they can be laid out without their contents, but still loading the script blocks page load. Are there other best practices for speeding up pages with OpenX?
We load our ads in iframes to avoid the problem you're having. We size div and the iframe the same, with the iframe pointing to a page which just contains the ad snippet (you can pass the zone and other required options as parameters to that page).
cheers
Lee
We lazy-load OpenX's code. Instead of putting the single-page call at the top of the page, we put it at the bottom. After the page has loaded, the call will get the banner data and a custom code will add the correct banners in the correct zones.
The code below requires a proper DOM. If you have jQuery, DOMAssistant, FlowJS, etc, the DOM should be fixed for you.
This code will work with normal banners with images, flash, or HTML content. It may not work in some cases like when using banners from external providers (adform, etc). For that you may need to hack the code a bit.
How to use it?
add your SinglePageCall code towards the end of your HTML code
add this code under the SPC code.
after half a second or so, your OpenX code should be ready, and the code below will put the banners within the specified DIVs.
Oh, yeah, you need to add to your HTML code some DIVs as place holders for your banners. By default I have these banners set with CSS class "hidden" which totally hides the DIVs (with visibility, display, and height). Then, after the banner in a given DIV is successfully loaded, we remove the hidden class and the DIV (and the banner within) become visible.
Use at your own risk! :) Hope it helps
(function(){
if (!document || !document.getElementById || !document.addEventListener || !document.removeClass) {
return; // No proper DOM; give up.
}
var openx_timeout = 1, // limit the time we wait for openx
oZones = new Object(), // list of [div_id] => zoneID
displayBannerAds; // function.
// oZones.<divID> = <zoneID>
// eg: oZones.banner_below_job2 = 100;
// (generated on the server side with PHP)
oZones.banner_top = 23;
oZones.banner_bottom = 34;
displayBannerAds = function(){
if( typeof(OA_output)!='undefined' && OA_output.constructor == Array ){
// OpenX SinglePageCall ready!
if (OA_output.length>0) {
for (var zone_div_id in oZones){
zoneid = oZones[zone_div_id];
if(typeof(OA_output[zoneid])!='undefined' && OA_output[zoneid]!='') {
var flashCode,
oDIV = document.getElementById( zone_div_id );
if (oDIV) {
// if it's a flash banner..
if(OA_output[zoneid].indexOf("ox_swf.write")!=-1)
{
// extract javascript code
var pre_code_wrap = "<script type='text/javascript'><!--// <![CDATA[",
post_code_wrap = "// ]]> -->";
flashCode = OA_output[zoneid].substr(OA_output[zoneid].indexOf(pre_code_wrap)+pre_code_wrap.length);
flashCode = flashCode.substr(0, flashCode.indexOf(post_code_wrap));
// replace destination for the SWFObject
flashCode = flashCode.replace(/ox\_swf\.write\(\'(.*)'\)/, "ox_swf.write('"+ oDIV.id +"')");
// insert SWFObject
if( flashCode.indexOf("ox_swf.write")!=-1 ){
eval(flashCode);
oDIV.removeClass('hidden');
}// else: the code was not as expected; don't show it
}else{
// normal image banner; just set the contents of the DIV
oDIV.innerHTML = OA_output[zoneid];
oDIV.removeClass('hidden');
}
}
}
} // end of loop
}//else: no banners on this page
}else{
// not ready, let's wait a bit
if (openx_timeout>80) {
return; // we waited too long; abort
};
setTimeout( displayBannerAds, 10*openx_timeout );
openx_timeout+=4;
}
};
displayBannerAds();
})();
OpenX has some documentation on how to make their tags load asynchronously:
http://docs.openx.com/ad_server/adtagguide_synchjs_implementing_async.html
I've tested it, and it works well in current Chrome/Firefox.
It takes some manual tweaking of their ad code. Their example of how the ad tags should end up:
<html>
<head></head>
<body>
Some content here.
Ad goes here.
<!-- Preserve space while the rest of the page loads. -->
<div id="placeholderId" style="width:728px;height:90px">
<!-- Fallback mechanism to use if unable to load the script tag. -->
<noscript>
<iframe id="4cb4e94bd5bb6" name="4cb4e94bd5bb6"
src="http://d.example.com/w/1.0/afr?auid=8&target=
_blank&cb=INSERT_RANDOM_NUMBER_HERE"
frameborder="0" scrolling="no" width="728"
height="90">
<a href="http://d.example.com/w/1.0/rc?cs=
4cb4e94bd5bb6&cb=INSERT_RANDOM_NUMBER_HERE"
target="_blank">
<img src="http://d.example.com/w/1.0/ai?auid=8&cs=
4cb4e94bd5bb6&cb=INSERT_RANDOM_NUMBER_HERE"
border="0" alt=""></a></iframe>
</noscript>
</div>
<!--Async ad request with multiple parameters.-->
<script type="text/javascript">
var OX_ads = OX_ads || [];
OX_ads.push({
"slot_id":"placeholderId",
"auid":"8",
"tid":"4",
"tg":"_blank",
"r":"http://redirect.clicks.to.here/landing.html",
"rd":"120",
"rm":"2",
"imp_beacon":"HTML for client-side impression beacon",
"fallback":"HTML for client-side fallback"
});
</script>
<!-- Fetch the Tag Library -->
<script type="text/javascript" src="http://d.example.com/w/1.0/jstag"></script>
Some other content here.
</body>
</html>
Following #Rafa excellent answer, i'm using this code to invoke OpenX banners after the page loads. I'm using jquery as well and had to add a new replace call for the "document.write" that flash banners use, and replacing it with "$('#"+ oDIV.id +"').append" instead. I'm using a custom "my_openx()" call, to replace "OA_show()". My banners area called by the zone_id and are wrapped inside a div, like this:
<div id="openx-4"><script>wm_openx(4);</script></div>
It's working :)
<script type="text/javascript">
$is_mobile = false;
$document_ready = 0;
$(document).ready(function() {
$document_ready = 1;
if( $('#MobileCheck').css('display') == 'inline' ) {
$is_mobile = true;
//alert('is_mobile: '+$is_mobile);
}
});
function wm_openx($id) {
if($is_mobile) return false;
if(!$document_ready) {
setTimeout(function(){ wm_openx($id); },1000);
return false;
}
if(typeof(OA_output[$id])!='undefined' && OA_output[$id]!='') {
var flashCode,
oDIV = document.getElementById('openx-'+$id);
if (oDIV) {
// if it's a flash banner..
if(OA_output[$id].indexOf("ox_swf.write")!=-1) {
// extract javascript code
var pre_code_wrap = "<script type='text/javascript'><!--// <![CDATA[",
post_code_wrap = "// ]]> -->";
flashCode = OA_output[$id].substr(OA_output[$id].indexOf(pre_code_wrap)+pre_code_wrap.length);
flashCode = flashCode.substr(0, flashCode.indexOf(post_code_wrap));
// replace destination for the SWFObject
flashCode = flashCode.replace(/ox\_swf\.write\(\'(.*)'\)/, "ox_swf.write('"+ oDIV.id +"')");
flashCode = flashCode.replace(/document.write/, "$('#"+ oDIV.id +"').append");
// insert SWFObject
if( flashCode.indexOf("ox_swf.write")!=-1 ) {
//alert(flashCode);
eval(flashCode);
//oDIV.removeClass('hidden');
}// else: the code was not as expected; don't show it
}else{
// normal image banner; just set the contents of the DIV
oDIV.innerHTML = OA_output[$id];
//oDIV.removeClass('hidden');
}
}
}
//OA_show($id);
}
</script>
I was looking for this to load advertising from my openX server only when the advertising should be visible. I'm using the iFrame version of openX which is loaded in a div. The answer here put me on my way to solving this problem, but the posted solution is a bit too simple. First of all, when the page is not loaded from the top (in case the user enters the page by clicking 'back') none of the divs are loaded. So you'll need something like this:
$(document).ready(function(){
$(window).scroll(lazyload);
lazyload();
});
also, you'll need to know what defines a visible div. That can be a div that's fully visible or partially visible. If the bottom of the object is greater or equal to the top of the window AND the top of the object is smaller or equal to the bottom of the window it should be visible (or in this case: loaded). Your function lazyload may look like this:
function lazyload(){
var wt = $(window).scrollTop(); //* top of the window
var wb = wt + $(window).height(); //* bottom of the window
$(".ads").each(function(){
var ot = $(this).offset().top; //* top of object (i.e. advertising div)
var ob = ot + $(this).height(); //* bottom of object
if(!$(this).attr("loaded") && wt<=ob && wb >= ot){
$(this).html("here goes the iframe definition");
$(this).attr("loaded",true);
}
});
}
Tested on all major browsers and even on my iPhone, works like a charm!!