FB.Canvas.getPageInfo not working - facebook

I am working on a FB app and used FB.Canvas.getPageInfo to get the scroll of the canvas to set popups in the screen center because the application is not scrolling but its the fb canvas which is scrolling and to find the center of the screen on long pages i need to get the number of pixels the canvas is scrolled and then with some plus minus i get the screen center of current page position. This was working fine till yesterday but is not since morning, I have tried alot but no success yet.
the code is called in setTimeout function, until the value is received I forcefully set my popup's dispaly to none and show a loader image.
remember it was working fine til last night
here is the code
$('.popup-call-local').live('click', function(event){
//FB.Canvas.getPageInfo(function(info){alert(info.scrollTop);});
var view_name = this.id;
var check_view_name = view_name.replace(/_/g, '-');
if($('#'+check_view_name).length > 0){
$('#popupDiv').css('height',$('.wrap').css('height'));
$('#popupDiv').css('display','block');
$('#popupDiv').css('z-index',1000);
var x = Number((window.screen.width - 400) / 2);
var y = Number(event.pageY)+ 10;
$('#popupDiv').html('<img src="<?php echo base_url(); ?>images/loaderblack.gif" style="position:absolute; z-index:50000; left:'+x+'px; top:'+y+'px;" />');
$('#'+check_view_name).css('z-index',2000);
var viewportHeight = window.screen.height;
var windowScrolled = -1;
$foo = jQuery('#'+check_view_name),
elWidth = $foo.width(),
elHeight = $foo.height(),
elOffset = $foo.offset();
setTimeout(function(){FB.Canvas.getPageInfo(function(info){windowScrolled=info.scrollTop; while(windowScrolled == -1){
$('#'+check_view_name).css('display','none');}
var v = (((viewportHeight - elHeight) / 2) + (windowScrolled) - 100); if(v<=0){v=Number(v)*Number(-1);}$('#popupDiv').html('');$('#'+check_view_name).css('display','block');$('#spinner').css('display','none');$('#'+check_view_name).css('top', Number(v) + 'px');});}, 3000);
}else{
return false;
}
});
EDIT
well
just found that its a facebook bug reported here
http://developers.facebook.com/bugs/185097921606322?browse=search_4f60961cc946d7143000700

Related

Preload Images for Photoswipe Gallery

So I have an array of images I want to load into a gallery using Photoswipe, but I'm having trouble predefining the image width and height. Specifically, I think I need to preload the images
Here's my JS to render the page, here I'm defining slides and listing as a local variable for the ejs page to use:
var sizeOf = require('image-size');
var url = require('url');
var http = require('http');
var slideshow = [];
for(var i = 0; i < listing.listing_images.length; i++) {
var image = listing.listing_images[i];
var width, height = 0;
var imgUrl = image.url;
var options = url.parse(imgUrl);
http.get(options, function (response) {
var chunks = [];
response.on('data', function (chunk) {
chunks.push(chunk);
}).on('end', function() {
var buffer = Buffer.concat(chunks);
**height = sizeOf(buffer).height;
width = sizeOf(buffer).width;**
});
});
var item = {
src: image.url,
h: height,
w: width
};
slideshow.push(item);
}
res.render('example.ejs', {
listing: listing,
slides: slideshow
});
And here is the script in the ejs page :
<% var slides = locals.slides %>
<script>
$('document').ready(function() {
var pswpElement = document.querySelectorAll('.pswp')[0];
// build items array using slideshow variable
var items = <%- JSON.stringify(slides) %>;
console.log(items);
// grab image
if (items.length > 0) {
// define options (if needed)
var options = {
// optionName: 'option value'
// for example:
index: 0 // start at first slide
};
// Initializes and opens PhotoSwipe
var gallery = new PhotoSwipe( pswpElement, PhotoSwipeUI_Default, items, options);
gallery.init();
}
</script>
Basically what's happening is the array of photoswipe items is being passed in fine, but the width and height aren't set until photoswipe initializes and triggers the img to load. So the images don't show, because their height and width aren't set yet.
Is there a way to trigger the loading of the images in the slideshow array so that the width & height are set before passing to Photoswipe? I've also tried seeing if I could just set them initially to 0, and then try and update the height and width later and try to force photoswipe to reload, but photoswipe doesn't recognize the image's new height/width.
Sorry if any of this is unclear/muddled with ejs nonsense, feel free to ask anything and I'd love to clarify.
Thanks
Ended up solving this leveraging the API:
gallery.listen('gettingData', function(index, item) {
// index - index of a slide that was loaded
// item - slide object
var img = new Image();
img.src = item.src;
item.h = img.height;
item.w = img.width;
});
gallery.invalidateCurrItems();
// updates the content of slides
gallery.updateSize(true);
If anyone happens to be reading this and there's a better way to read image size without creating a new img, or optimize this I'd love suggestions. :)

Facebook Tracking of In-Page Events with Conversion Pixel Code

Full disclosure - I'm not a programmer, but I'm the only one in my organisation who might be able to get this working. Can anyone help with the following please?
I'm trying to use Facebook's conversion pixel code to track certain button clicks on our site. Facebook's developer docs give the following instructions for tracking in-page events:
After the base code snippet is installed, you can track in-page actions, such as clicks on a button, by making a _fbq.push('track') call for the conversion pixel through registering different event handlers on an HTML DOM element. For example:
function trackConversionEvent(val, cny) {
var cd = {};
cd.value = val;
cd.currency = cny;
_fbq.push(['track', '<pixel_id>', cd]);
}
<button onClick="trackConversionEvent('10.00','USD');" /
The problem I'm facing is it's not clear to me what Facebook means by "the base code snippet". My initial assumption was that it's the conversion pixel code they give you to install in the head section of the page, i.e.
<!-- Facebook Conversion Code -->
<script>(function() {
var _fbq = window._fbq || (window._fbq = []);
if (!_fbq.loaded) {
var fbds = document.createElement('script');
fbds.async = true;
fbds.src = '//connect.facebook.net/en_US/fbds.js';
var s = document.getElementsByTagName('script')[0];
s.parentNode.insertBefore(fbds, s);
_fbq.loaded = true;
}
})();
window._fbq = window._fbq || [];
window._fbq.push(['track', '<pixel_id>', {'value':'0.00','currency':'USD'}]);
</script>
<noscript><img height="1" width="1" alt="" style="display:none" src="https://www.facebook.com/tr?ev=<pixel_id>&cd[value]=0.00&cd[currency]=USD&noscript=1" /></noscript>
However, if I install the above on our page it loads/fires the conversion pixel code each time the page loads rather than on the button click (presumably because it's typically used on a thank you/confirmation page). Can anyone shed any light on this for me? I believe I understand where to position the onClick code to associate it with a button click but I'm struggling to understand where I need to position the trackConversionEvent code and what the base code snippet is. Through testing, I know that removing the following lines from the larger code snippet stops the pixel from loading:
window._fbq = window._fbq || [];
window._fbq.push(['track', '<pixel_id>', {'value':'0.00','currency':'USD'}]);
but I'm not sure if that's actually what I need to do. Do I for example, need to replace those two lines with the trackConversionEvent code so that the pixel doesn't fire when the page loads but the onClick code actually functions instead when the button is clicked?
Many thanks in advance for any pointers or suggestions.
This should work, I.ve just tested on a blog based on WP.
<!-- Facebook Conversion Code -->
<script>(function() {
var _fbq = window._fbq || (window._fbq = []);
if (!_fbq.loaded) {
var fbds = document.createElement('script');
fbds.async = true;
fbds.src = '//connect.facebook.net/en_US/fbds.js';
var s = document.getElementsByTagName('script')[0];
s.parentNode.insertBefore(fbds, s);
_fbq.loaded = true;
}
})();
window._fbq = window._fbq || [];
</script>
<noscript><img height="1" width="1" alt="" style="display:none" src="https://www.facebook.com/tr?ev=<pixel_id>&cd[value]=0.00&cd[currency]=USD&noscript=1" /></noscript>
<!-- End Of Facebook Conversion Code -->
This is the event handler that you could bind to any button, link or any DOM element::
function trackConversionEvent(val, cny) {
var cd = {};
cd.value = val;
cd.currency = cny;
_fbq.push(['track', '<pixel_id>', cd]);
}
<button onClick="trackConversionEvent('10.00','USD');"

HTML5 Video - currentTime not setting properly on iPhone

I have a basic HTML5 video set up from which I load one of four videos. The problem I'm having is that when I load the next video, it continues playing from the previous time position. Efforts to set the currentTime property seem to be either short lived or ignored entirely.
I have added listeners to a collection of events and have something like this in each one;
myPlayer.addEventListener("loadeddata", function() {
console.log(" loadeddata: before = " + myPlayer.currentTime);
myPlayer.currentTime = 0.1;
console.log(" loadeddata: after = " + myPlayer.currentTime);
}, false);
Sometimes I see the time change for one event but not persist correctly;
durationchange: before = 19.773332595825195
durationchange: after = 0.10000000149011612
loadedmetadata: before = 0.10000000149011612
loadedmetadata: after = 19.773332595825195
loadeddata: before = 19.773332595825195
loadeddata: after = 0.10000000149011612
canplay: before = 0.10000000149011612
canplay: after = 19.773332595825195
And sometimes it never even seems to set at all;
durationchange: before = 50.66666793823242
durationchange: after = 50.66666793823242
loadedmetadata: before = 50.66666793823242
loadedmetadata: after = 50.66666793823242
loadeddata: before = 50.66666793823242
loadeddata: after = 50.66666793823242
canplay: before = 50.66666793823242
canplay: after = 50.66666793823242
This seems similar to the issue here but there didn't seem to be any resolution. Has anyone encountered this issue on iPhone before?
TL;DR: change currentTime on the loadeddata event. This works for audio too.
It looks like Safari (and the problem is still appearing for me on Safari 11.1) is Safari will not allow currentTime to be changed when a video is first loaded IF it hasn't loaded a frame for that currentTime yet. The bigger problem: the wrong solution can break Chrome (and likely other browsers too).
Fortunately, we have a lot of events we can listen for while media is loading:
During the loading process of an audio/video, the following events occur, in this order:
loadstart
durationchange
loadedmetadata
loadeddata
progress
canplay
canplaythrough
-W3Schools (I know it's not a preferred source, but I couldn't find the same info on MDN)
I tried adjusting currentTime on different events, but on the first 3 events, Safari would move the time back to 0; and on 5 and 6 it seemed to prevent the video from playing in Chrome, because it would get stuck at currentTime (which I could've worked around, but I thought there was a better solution).
(I didn't want to have to load the whole file to go to the right spot, because I want to support hefty videos. So canplaythrough wasn't an option for me.)
The description for the loadeddata event reads:
The loadeddata event is fired when the first frame of the media has finished loading.
-MDN
When I changed currentTime on loadeddata, Safari could tell that the frame was loaded and available, and would update correctly. It also wouldn't cause Chrome to freeze in a single spot while playing.
The problem and solution are identical for audio.
From my findings the issue seems to be that on iPhone only (iPad works fine) the currentTime property will not be set correctly until the "canplaythrough" event, however changing the currentTime at that point will cause a noticeable hiccup. The solution for that would be to intentionally pause the video after calling load...
myVideo.load();
myVideo.pause();
...and then call play in the event when the time has reset.
The second problem however is when the duration of the new movie is shorter then the currentTime position. In this case not only does currentTime fail to set but "canplaythrough" is never called, and QT just sits at the end of the video doing nothing.
I discovered the solution to both problems was to force a secondary load if the currentTime was not reset in the event BEFORE "canplaythrough". Its a bit round about with the timer callback but it seems to do the trick;
var myVideo = document.getElementById("video1");
myVideo.addEventListener("canplay", function() {
console.log(" canplay: before = " + myVideo.currentTime);
myVideo.currentTime = 0.1;
console.log(" canplay: after = " + myVideo.currentTime);
if( myVideo.currentTime < 1 ) {
myVideo.play();
}
else {
myVideo.load();
myVideo.pause();
setTimeout(checkStarted, 500);
}
}, false);
function checkStarted()
{
console.log(" checkStarted called");
myVideo.play();
}
I had to set the preload attribute to metadata (on the HTML of the main video element) and set the currentTime of the video element within the loadedmetadata event listener.
<video id="myVideo" preload="metadata">
<source src="/path/to/video" type="video/mp4">
</video>
JS
VideoEl.addEventListener('loadedmetadata', VideoMetaDataLoaded);
function VideoMetaDataLoaded() {
VideoEl.currentTime = newTime;
}
Below is my Angular/Ionic solution to restore the video position. It works on IOS, Android, Chrome and Safari.
HTML:
<video preload="metadata"
poster="{{ resource.thumbnail_file }}"
playsinline webkit-playsinline
#videos>
...
</video>
Typescript:
#ViewChildren('videos') videos: QueryList<any>;
videoCache: Map<number, number> = new Map<number, number>();
private restoreVideoPositions() {
var context = this;
setTimeout(() => {
this.videos.forEach(function (item, idx) {
var video = item.nativeElement;
var currentTime = context.videoCache.get(video.id);
if (currentTime != null && currentTime > 0) {
console.log('add listener', currentTime);
video.addEventListener("loadeddata", function () {
if (video.readyState >= 3) {
video.currentTime = currentTime;
// video.play();
}
});
video.load();
}
});
}, 0);
}
private storeVideoPositions() {
var context = this;
this.videoCache.clear()
this.videos.forEach(function (item, idx) {
var video = item.nativeElement;
video.pause();
context.videoCache.set(video.id, video.currentTime)
});
}
I used a combination of the last two answers here, but had to reduce the ready state limit to 2 (HTMLVideoElement.prototype.HAVE_CURRENT_DATA) as the loadeddata event on iOS would often never come in higher than 2.
With help from the other answers here I came up with the next solution:
HTMLVideoElement.prototype.playFromTime = function(currentTime){
let that = this;
that.load();
that.pause();
that.currentTime = currentTime;
let loadedMetadata;
loadedMetadata = function(event){
that.currentTime = currentTime;
that.removeEventListener("loadedmetadata", loadedMetadata);
}
if(that.currentTime !== currentTime){
that.addEventListener("loadedmetadata", loadedMetadata);
}
that.play();
}
//usage example:
myVidElement.playFromTime(20);
Which in my situation works on an iPhone on Safari, Safari on the desktop, Firefox on macOS, Chrome on macOS. That's all I have tested for now.
Had the same problem with a play video on scroll with React. The following solved it for me.
useEffect(() => {
videoRef.current.load();
}, []);
const { render } = ReactDOM;
const { useState, useEffect, useRef } = React;
const Video = ({ src, height, length }) => {
const [currentTime, setCurrentTime] = useState(0);
const videoRef = useRef(null);
useEffect(() => {
// This is needed for IOS
videoRef.current.load();
window.addEventListener("scroll", handleScroll);
return () => window.removeEventListener("scroll", handleScroll);
}, []);
const getCurrentTime = () => {
const percentScrolled = window.scrollY / (height - window.innerHeight);
return length * percentScrolled;
};
const handleScroll = (e) => {
const time = getCurrentTime();
videoRef.current.currentTime = time;
setCurrentTime(time);
};
return (
<div style={{ height }}>
<p>Time: {currentTime.toFixed(2)}s</p>
<video ref={videoRef} muted playsInline>
<source src={src} type="video/mp4" />
Your browser does not support the video tag.
</video>
</div>
);
};
const App = () => {
return (
<Video
length={5}
height={3000}
src="https://lqez.github.io/js/airpodsvf/video.mp4"
/>
);
};
render(<App />, document.getElementById("root"));
body {
background: black;
}
p {
color: slategrey;
top: 0;
position: fixed;
z-index: 1;
padding: 20px;
}
video {
top: 60px;
position: fixed;
width: 100%;
display: block;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.9.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.9.0/umd/react-dom.production.min.js"></script>
<div id="root"></div>
this is a problem with chrome on local assets. happened with me. when i was serving video from local assets and setting time it resets the video to 0.
so the solution that worked for me was serving the video from s3 bucket.

Javascript horizontal slider not working

I'm using an old version of the Slidedeck Plugin (v.1.4.5) and I have a javascript problem with one of the skins I'm using. More precisely, the horizontal slides are stitched together and I can't figure out how to fix this. I want each slide to be independent, without any content from the next or previous slide to be seen on the active slide.
You can see in the screenshot from below that the middle slide has visible content from the previous and next slide, which obviously I don't want to be visible.
I should mention that I have very limited knowledge of javascript / jQuery, and I suspect it's a js problem because the CSS is the same for all skins - the only variable is the script used by each skin.
You can see the slider behavior on this website and below is the full script used for the slider skin. I would appreciate any help on this. To change the slides click on each slide arrow from left or right side, or you can use the directional keys on the keyboard.
(function($){
SlideDeckSkin['fullwidth-sexy'] = function(slidedeck){
var ns = 'fullwidth-sexy';
var elems = {};
elems.slidedeck = $(slidedeck);
elems.frame = elems.slidedeck.closest('.skin-' + ns);
// Disable spines as this skin is not meant to function with spines on
elems.slidedeck.slidedeck().setOption('hideSpines', true);
elems.frame.append('PreviousNext');
elems.slidedeck.append('<div class="' + ns + '-mask left"></div><div class="' + ns + '-mask right"></div>');
elems.frame.find('.sd-' + ns + '-nav').bind('click', function(event){
event.preventDefault();
var $this = $(this);
elems.slidedeck.slidedeck().options.pauseAutoPlay = true;
if($this.hasClass('prev')){
elems.slidedeck.slidedeck().prev();
} else {
elems.slidedeck.slidedeck().next();
}
});
};
$(document).ready(function(){
$('.skin-fullwidth-sexy .slidedeck').each(function(){
if(typeof($.data(this, 'skin-fullwidth-sexy')) == 'undefined' || $.data(this, 'skin-fullwidth-sexy') == null){
$.data(this, 'skin-fullwidth-sexy', new SlideDeckSkin['fullwidth-sexy'](this));
}
});
});
})(jQuery);
The following might work, but it is hard to test without an example of what you are trying to do.
What I did is added a unique number to the ns variable (for namespace I assume.) This number is passed to the callback of the each function. (doc)
(function($){
SlideDeckSkin['fullwidth-sexy'] = function(slidedeck,uniqueName){
var ns = 'fullwidth-sexy'+uniqueName;
var elems = {};
elems.slidedeck = $(slidedeck);
elems.frame = elems.slidedeck.closest('.skin-' + ns);
// Disable spines as this skin is not meant to function with spines on
elems.slidedeck.slidedeck().setOption('hideSpines', true);
elems.frame.append('PreviousNext');
elems.slidedeck.append('<div class="' + ns + '-mask left"></div><div class="' + ns + '-mask right"></div>');
elems.frame.find('.sd-' + ns + '-nav').bind('click', function(event){
event.preventDefault();
var $this = $(this);
elems.slidedeck.slidedeck().options.pauseAutoPlay = true;
if($this.hasClass('prev')){
elems.slidedeck.slidedeck().prev();
} else {
elems.slidedeck.slidedeck().next();
}
});
};
$(document).ready(function(){
$('.skin-fullwidth-sexy .slidedeck').each(function(n){
if(typeof($.data(this, 'skin-fullwidth-sexy')) == 'undefined' || $.data(this, 'skin-fullwidth-sexy') == null){
$.data(this, 'skin-fullwidth-sexy', new SlideDeckSkin['fullwidth-sexy'+n](this,n));
}
});
});
})(jQuery);

JavaScript Mouse position over an element (code not working)

I want to display the mouse position when its inside an element.. heres the code:
Mouse Events Example
function GetMousePositionInElement(ev, element)
{
var osx = element.offsetX;
var osy = element.offsetY;
var bottom = osy + element.height();
var x = ev.pageX - osx;
var y = bottom - ev.pageY;
return { x: x, y: y, y_fromTop: element.height() - y };
}
function handleEvent(oEvent) {
var oTextbox = document.getElementById("txt1");
var elem = document.getElementById("div1");
var xp = GetMousePositionInElement(oEvent, elem).x;
var yp = GetMousePositionInElement(oEvent, elem).y;
oTextbox.value += "\n x = " + xp + "y= " + yp;
}
Use your mouse to click and double click the red square.
div style="width: 100px; height: 100px; background-color: red"
onmouseover="handleEvent(event)"
id="div1"> /div
textarea id="txt1" rows="15" cols="50"> /textarea>
There is a problem in the code. Mouse position is not displayed inside the texArea. What changes do i have to make for the code to work and work correctly? (of-cource not all of the code is displayed and i removed some of the < and > inoder to show you some parts of the code that are not displayed otherwise but the code syntax is correct, thats not the problem)
Thank you.
var osy = element.offsetY;
There's no such property as offsetY. You may be thinking of offsetTop. However note the offsetLeft/​Top values are relative to the offsetParent not the page. If you want page-relative co-ordinates you would need to loop through offsetParents, or, since you seem to be including jQuery, call its offset function that does just that:
var offset= $(element).offset();
var osx= offset[0], osy= offset[1];
var bottom = osy + element.height();
element is a DOM HTMLDivElement object, not a jQuery wrapper object, so it doesn't have the height() method. Either add the wrapper:
var bottom= osy+$(element).height();
or use the equivalent DOM method:
var bottom= osy+element.offsetHeight;
var y = bottom - ev.pageY;
Note pageY is not part of the DOM Events standard and also not available in IE. You can calculate it by using the standard clientY property and adjusting for the page's scrollTop. Again, jQuery does this for you, adding the Firefox pageY extension to all browsers, when you use its own methods to bind your event handler:
$('#div1').mouseover(handleEvent);
instead of the inline onmouseover=... event handler attribute.