Ionic scrollTop "Cannot read property 'scrollTo' of null" (still exists in 1.0.0-rc.1) - ionic-framework

This bug was referred to here: in ionic changing route causes "TypeError: Cannot read property 'scrollTo' of null"
The answer says that this bug was fixed in beta-13, but I'm using 1.0.0-rc.1 and the bug still appears.
In my case, it the error is showing when navigating back to a page that uses $ionicScrollDelegate.scrollTop()
Is anyone else getting this error after updating to rc.1?
EDIT:
I find that if I do not call $ionicScrollDelegate.scrollTop() automatically when my view loads, the error does not come up. Should I be calling scrollTop() within a specific Ionic event that waits for the right time?

Had the same problem, even with v1.0.0 "uranium-unicorn".
Wrapping the scroll call into a $timeout helped - this is what it looks like in my code:
$timeout(function() {
$ionicScrollDelegate.scrollTo(scrollPosition.left, scrollPosition.top);
}, 0);

You can just put it in
$ionicPlatform.ready(function () {
$ionicScrollDelegate.scrollTop();
})

Im late to this but was getting the same error but by calling the scroll top element with:
$ionicScrollDelegate.scrollTop();
but rather:
var scrollTop = e.detail.scrollTop;
and fixed my by using the following:
var scrollTop = $ionicScrollDelegate.getScrollPosition().top;
Im also using js scrolling as it seems to work better with the scrolla-sista plugin so I have the following in my config block at the start of my app
$ionicConfigProvider.scrolling.jsScrolling(true);
where their docs state:
Whether to use JS or Native scrolling. Defaults to native scrolling. Setting this to true has the same effect as setting each ion-content to have overflow-scroll='false'.
I hope this helps someone

For what it's worth, I saw this solution on this thread here and it worked for me with version 1.0.0-beta.14
If upgrading to version 1.0.0-beta.14 is not an option, you can change the ionic-bundle.js file with the following:
Approximately Line 39910:
this.scrollTop = function(shouldAnimate) {
this.resize().then(function() {
if(typeof scrollView !== 'undefined' && scrollView !== null){
scrollView.scrollTo(0, 0, !!shouldAnimate);
}
});
};
And Approximately line 39813:
if (!angular.isDefined(scrollViewOptions.bouncing)) {
ionic.Platform.ready(function() {
if(!scrollView){
return;
}
scrollView.options.bouncing = true;
if(ionic.Platform.isAndroid()) {
// No bouncing by default on Android
scrollView.options.bouncing = false;
// Faster scroll decel
scrollView.options.deceleration = 0.95;
}
});
}

Please change
e.detail.scrollTop
to
e.target.scrollTop
then this will Work

Related

Same page appears while using ionic native transition plugin?

I am using ionic native transition plugin in my app. I am using slide up transition for pages.It works,but when state changes it shows the same page for a short period of time and then the other page (the page where I want to switch) appears. Here is the github link.I tried with different values for the default options, but it doesn't solve my problem. any help will be appreciated
I'm not sure if your issue is the same that I had (when transition to next/previous state begins the "new state" which it's supposed to transition to is shown in the "old view" before/during animation) but here is what I did. I found a solution which is to add a timeout to the state change in the stateGo() function in the ionic.native-transitions(.min).js which leads to it being run as the last function. The following code works on both iOS and Android devices.
function stateGo() {
var state = arguments.length <= 0 || arguments[0] === undefined ? null : arguments[0];
var stateParams = arguments.length <= 1 || arguments[1] === undefined ? {} : arguments[1];
var transitionOptions = arguments.length <= 2 || arguments[2] === undefined ? null : arguments[2];
var stateOptions = arguments.length <= 3 || arguments[3] === undefined ? {} : arguments[3];
if (!state) {
$log.debug('[native transition] cannot change state without a state...');
return;
}
unregisterToStateChangeStartEvent();
transition(transitionOptions);
if (ionic.Platform.isIOS()) {
$timeout(function() {
$state.go(state, stateParams, stateOptions);
});
} else {
$state.go(state, stateParams, stateOptions);
}
}
I decided to add the check for an iOS device and run the timeout only in that case because it was only occurring in iOS devices and the timeout perhaps made Android devices flicker a little on the transition (I could be paranoid and this not really even occurring, or is due to large images on the content on my app).
Same fix probably also works in the case that you are using locationurl instead in which case you just set timeout to the "$location.url(url);" function.
Not sure if this would be the final solution for this problem but it works for now and hopefully the plugin will be fixed soon so this problem won't bother anyone else.
The same issue was on my side as well when using:
$scope.$on('$ionicView.enter', function(event, viewData) {
var transitionDirection = viewData.direction !== "back" ? "left": "right";
var options = {
"direction": transitionDirection,
"duration": 600,
"androiddelay": 75
};
window.plugins.nativepagetransitions.slide(
options,
function () {},
function () {}
);
});
However, when I changed the '$ionicView.enter' event to '$ionicView.beforeEnter', it solved the case for me. Not sure if that is a proper solution though.

shareThis click/hover events with AJAX

I am running into an issue where I am making an AJAX call to load images into a carousel, and it is breaking the shareThis click/hover events that are associated with each image (email, twitter, and facebook).
I have read all over that by doing
stButtons.locateElements();
it should resolve the issue, but it does not. Nothing happens and the buttons remain unclickable/no hover event. I have also tried reloading the script:
var switchTo5x = true;
$.getScript('//ws.sharethis.com/button/buttons.js', function () {
stLight.options({ "publisher": "publisher-code" });
});
and that just leads to button.js throwing this error: "Uncaught TypeError: Cannot call method 'process' of null".
Any thoughts on how I can rebind the events?
I ended up figuring out a solution, although there is still an error being thrown by button.js.
Before I run getScript, I set stButtons to null and that solved my issue. Here was the end result:
if (stButtons) {
// Reset the share this buttons to null
stButtons = null;
try {
// Reload the script from scratch
var switchTo5x = true;
$.getScript('//ws.sharethis.com/button/buttons.js', function () {
stLight.options({ "publisher": "pub-id" });
});
}
catch (err) { }
}
I am still getting this error from button.js: Uncaught TypeError: Cannot read property 'messageQueueInstance' of null. But, it is working now. Will look more into this error another time.

can't tap on item in google autocomplete list on mobile

I'm making a mobile-app using Phonegap and HTML. Now I'm using the google maps/places autocomplete feature. The problem is: if I run it in my browser on my computer everything works fine and I choose a suggestion to use out of the autocomplete list - if I deploy it on my mobile I still get suggestions but I'm not able to tap one. It seems the "suggestion-overlay" is just ignored and I can tap on the page. Is there a possibility to put focus on the list of suggestions or something that way ?
Hope someone can help me. Thanks in advance.
There is indeed a conflict with FastClick and PAC. I found that I needed to add the needsclick class to both the pac-item and all its children.
$(document).on({
'DOMNodeInserted': function() {
$('.pac-item, .pac-item span', this).addClass('needsclick');
}
}, '.pac-container');
There is currently a pull request on github, but this hasn't been merged yet.
However, you can simply use this patched version of fastclick.
The patch adds the excludeNode option which let's you exclude DOM nodes handled by fastclick via regex. This is how I used it to make google autocomplete work with fastclick:
FastClick.attach(document.body, {
excludeNode: '^pac-'
});
This reply may be too late. But might be helpful for others.
I had the same issue and after debugging for hours, I found out this issue was because of adding "FastClick" library. After removing this, it worked as usual.
So for having fastClick and google suggestions, I have added this code in geo autocomplete
jQuery.fn.addGeoComplete = function(e){
var input = this;
$(input).attr("autocomplete" , "off");
var id = input.attr("id");
$(input).on("keypress", function(e){
var input = this;
var defaultBounds = new google.maps.LatLngBounds(
new google.maps.LatLng(37.2555, -121.9245),
new google.maps.LatLng(37.2555, -121.9245));
var options = {
bounds: defaultBounds,
mapkey: "xxx"
};
//Fix for fastclick issue
var g_autocomplete = $("body > .pac-container").filter(":visible");
g_autocomplete.bind('DOMNodeInserted DOMNodeRemoved', function(event) {
$(".pac-item", this).addClass("needsclick");
});
//End of fix
autocomplete = new google.maps.places.Autocomplete(document.getElementById(id), options);
google.maps.event.addListener(autocomplete, 'place_changed', function() {
//Handle place selection
});
});
}
if you are using Framework 7, it has a custom implementation of FastClicks. Instead of the needsclick class, F7 has no-fastclick. The function below is how it is implemented in F7:
function targetNeedsFastClick(el) {
var $el = $(el);
if (el.nodeName.toLowerCase() === 'input' && el.type === 'file') return false;
if ($el.hasClass('no-fastclick') || $el.parents('.no-fastclick').length > 0) return false;
return true;
}
So as suggested in other comments, you will only have to add the .no-fastclick class to .pac-item and in all its children
I was having the same problem,
I realized what the problem was that probably the focusout event of pac-container happens before the tap event of the pac-item (only in phonegap built-in browser).
The only way I could solve this, is to add padding-bottom to the input when it is focused and change the top attribute of the pac-container, so that the pac-container resides within the borders of the input.
Therefore when user clicks on item in list the focusout event is not fired.
It's dirty, but it works
worked perfectly for me :
$(document).on({
'DOMNodeInserted': function() {
$('.pac-item, .pac-item span', this).addClass('needsclick');
}
}, '.pac-container');
Configuration: Cordova / iOS iphone 5

iOS 5 fixed positioning and virtual keyboard

I have a mobile website which has a div pinned to the bottom of the screen via position:fixed. All works fine in iOS 5 (I'm testing on an iPod Touch) until I'm on a page with a form. When I tap into an input field and the virtual keyboard appears, suddenly the fixed position of my div is lost. The div now scrolls with the page as long as the keyboard is visible. Once I click Done to close the keyboard, the div reverts to its position at the bottom of the screen and obeys the position:fixed rule.
Has anyone else experienced this sort of behavior? Is this expected? Thanks.
I had this problem in my application. Here's how I'm working around it:
input.on('focus', function(){
header.css({position:'absolute'});
});
input.on('blur', function(){
header.css({position:'fixed'});
});
I'm just scrolling to the top and positioning it there, so the iOS user doesn't notice anything odd going on. Wrap this in some user agent detection so other users don't get this behavior.
I had a slightly different ipad issue where the virtual keyboard pushed my viewport up offscreen. Then after the user closed the virtual keyboard my viewport was still offscreen. In my case I did something like the following:
var el = document.getElementById('someInputElement');
function blurInput() {
window.scrollTo(0, 0);
}
el.addEventListener('blur', blurInput, false);
This is the code we use to fix problem with ipad. It basically detect discrepancies between offset and scroll position - which means 'fixed' isn't working correctly.
$(window).bind('scroll', function () {
var $nav = $(".navbar")
var scrollTop = $(window).scrollTop();
var offsetTop = $nav.offset().top;
if (Math.abs(scrollTop - offsetTop) > 1) {
$nav.css('position', 'absolute');
setTimeout(function(){
$nav.css('position', 'fixed');
}, 1);
}
});
The position fixed elements simply don't update their position when the keyboard is up. I found that by tricking Safari into thinking that the page has resized, though, the elements will re-position themselves. It's not perfect, but at least you don't have to worry about switching to 'position: absolute' and tracking changes yourself.
The following code just listens for when the user is likely to be using the keyboard (due to an input being focused), and until it hears a blur it just listens for any scroll events and then does the resize trick. Seems to be working pretty well for me thus far.
var needsScrollUpdate = false;
$(document).scroll(function(){
if(needsScrollUpdate) {
setTimeout(function() {
$("body").css("height", "+=1").css("height", "-=1");
}, 0);
}
});
$("input, textarea").live("focus", function(e) {
needsScrollUpdate = true;
});
$("input, textarea").live("blur", function(e) {
needsScrollUpdate = false;
});
Just in case somebody happens upon this thread as I did while researching this issue. I found this thread helpful in stimulating my thinking on this issue.
This was my solution for this on a recent project. You just need to change the value of "targetElem" to a jQuery selector that represents your header.
if(navigator.userAgent.match(/iPad/i) != null){
var iOSKeyboardFix = {
targetElem: $('#fooSelector'),
init: (function(){
$("input, textarea").on("focus", function() {
iOSKeyboardFix.bind();
});
})(),
bind: function(){
$(document).on('scroll', iOSKeyboardFix.react);
iOSKeyboardFix.react();
},
react: function(){
var offsetX = iOSKeyboardFix.targetElem.offset().top;
var scrollX = $(window).scrollTop();
var changeX = offsetX - scrollX;
iOSKeyboardFix.targetElem.css({'position': 'fixed', 'top' : '-'+changeX+'px'});
$('input, textarea').on('blur', iOSKeyboardFix.undo);
$(document).on('touchstart', iOSKeyboardFix.undo);
},
undo: function(){
iOSKeyboardFix.targetElem.removeAttr('style');
document.activeElement.blur();
$(document).off('scroll',iOSKeyboardFix.react);
$(document).off('touchstart', iOSKeyboardFix.undo);
$('input, textarea').off('blur', iOSKeyboardFix.undo);
}
};
};
There is a little bit of a delay in the fix taking hold because iOS stops DOM manipulation while it is scrolling, but it does the trick...
None of the other answers I've found for this bug have worked for me. I was able to fix it simply by scrolling the page back up by 34px, the amount mobile safari scrolls it down. with jquery:
$('.search-form').on('focusin', function(){
$(window).scrollTop($(window).scrollTop() + 34);
});
This obviously will take effect in all browsers, but it prevents it breaking in iOS.
This issue is really annoying.
I combined some of the above mentioned techniques and came up with this:
$(document).on('focus', 'input, textarea', function() {
$('.YOUR-FIXED-DIV').css('position', 'static');
});
$(document).on('blur', 'input, textarea', function() {
setTimeout(function() {
$('.YOUR-FIXED-DIV').css('position', 'fixed');
$('body').css('height', '+=1').css('height', '-=1');
}, 100);
});
I have two fixed navbars (header and footer, using twitter bootstrap).
Both acted weird when the keyboard is up and weird again after keyboard is down.
With this timed/delayed fix it works. I still find a glitch once in a while, but it seems to be good enough for showing it to the client.
Let me know if this works for you. If not we might can find something else. Thanks.
I was experiencing same issue with iOS7. Bottom fixed elements would mess up my view not focus properly.
All started working when I added this meta tag to my html.
<meta name="viewport" content="width=device-width,initial-scale=1.0,maximum-scale=1.0,user-scalable=no,height=device-height" >
The part which made the difference was:
height=device-height
Hope that helps someone.
I've taken Jory Cunningham answer and improved it:
In many cases, it's not just one element who goes crazy, but several fixed positioned elements, so in this case, targetElem should be a jQuery object which has all the fixed elements you wish to "fix". Ho, this seems to make the iOS keyboard go away if you scroll...
Needless to mention you should use this AFTER document DOM ready event or just before the closing </body> tag.
(function(){
var targetElem = $('.fixedElement'), // or more than one
$doc = $(document),
offsetY, scrollY, changeY;
if( !targetElem.length || !navigator.userAgent.match(/iPhone|iPad|iPod/i) )
return;
$doc.on('focus.iOSKeyboardFix', 'input, textarea, [contenteditable]', bind);
function bind(){
$(window).on('scroll.iOSKeyboardFix', react);
react();
}
function react(){
offsetY = targetElem.offset().top;
scrollY = $(window).scrollTop();
changeY = offsetY - scrollY;
targetElem.css({'top':'-'+ changeY +'px'});
// Instead of the above, I personally just do:
// targetElem.css('opacity', 0);
$doc.on('blur.iOSKeyboardFix', 'input, textarea, [contenteditable]', unbind)
.on('touchend.iOSKeyboardFix', unbind);
}
function unbind(){
targetElem.removeAttr('style');
document.activeElement.blur();
$(window).off('scroll.iOSKeyboardFix');
$doc.off('touchend.iOSKeyboardFix blur.iOSKeyboardFix');
}
})();
I have a solution similar to #NealJMD except mine only executes for iOS and correctly determines the scroll offset by measuring the scollTop before and after the native keyboard scrolling as well as using setTimeout to allow the native scrolling to occur:
var $window = $(window);
var initialScroll = $window.scrollTop();
if (navigator.userAgent.match(/iPhone|iPad|iPod/i)) {
setTimeout(function () {
$window.scrollTop($window.scrollTop() + (initialScroll - $window.scrollTop()));
}, 0);
}
I have fixed my Ipad main layout content fixed position this way:
var mainHeight;
var main = $('.main');
// hack to detects the virtual keyboard close action and fix the layout bug of fixed elements not being re-flowed
function mainHeightChanged() {
$('body').scrollTop(0);
}
window.setInterval(function () {
if (mainHeight !== main.height())mainHeightChanged();
mainHeight = main.height();
}, 100);
I had a similar problem to #ds111 s. My website was pushed up by the keyboard but didn't move down when the keyboard closed.
First I tried #ds111 solution but I had two input fields. Of course, first the keyboard goes away, then the blur happens (or something like that). So the second input was under the keyboard, when the focus switched directly from one input to the other.
Furthermore, the "jump up" wasn't good enough for me as the whole page only has the size of the ipad. So I made the scroll smooth.
Finally, I had to attach the event listener to all inputs, even those, that were currently hidden, hence the live.
All together I can explain the following javascript snippet as:
Attach the following blur event listener to the current and all future input and textarea (=live): Wait a grace period (= window.setTimeout(..., 10)) and smoothly scroll to top (= animate({scrollTop: 0}, ...)) but only if "no keyboard is shown" (= if($('input:focus, textarea:focus').length == 0)).
$('input, textarea').live('blur', function(event) {
window.setTimeout(function() {
if($('input:focus, textarea:focus').length == 0) {
$("html, body").animate({ scrollTop: 0 }, 400);
}
}, 10)
})
Be aware, that the grace period (= 10) may be too short or the keyboard may still be shown although no input or textarea is focused. Of course, if you want the scrolling faster or slower, you may adjust the duration (= 400)
really worked hard to find this workaround, which in short looks for focus and blur events on inputs, and scrolling to selectively change the positioning of the fixed bar when the events happen. This is bulletproof, and covers all cases (navigating with <>, scroll, done button). Note id="nav" is my fixed footer div. You can easily port this to standard js, or jquery. This is dojo for those who use power tools ;-)
define([
"dojo/ready",
"dojo/query",
], function(ready, query){
ready(function(){
/* This addresses the dreaded "fixed footer floating when focusing inputs and keybard is shown" on iphone
*
*/
if(navigator.userAgent.match(/iPhone/i)){
var allInputs = query('input,textarea,select');
var d = document, navEl = "nav";
allInputs.on('focus', function(el){
d.getElementById(navEl).style.position = "static";
});
var fixFooter = function(){
if(d.activeElement.tagName == "BODY"){
d.getElementById(navEl).style.position = "fixed";
}
};
allInputs.on('blur', fixFooter);
var b = d.body;
b.addEventListener("touchend", fixFooter );
}
});
}); //end define
This is a difficult problem to get 'right'. You can try and hide the footer on input element focus, and show on blur, but that isn't always reliable on iOS. Every so often (one time in ten, say, on my iPhone 4S) the focus event seems to fail to fire (or maybe there is a race condition), and the footer does not get hidden.
After much trial and error, I came up with this interesting solution:
<head>
...various JS and CSS imports...
<script type="text/javascript">
document.write( '<style>#footer{visibility:hidden}#media(min-height:' + ($( window ).height() - 10) + 'px){#footer{visibility:visible}}</style>' );
</script>
</head>
Essentially: use JavaScript to determine the window height of the device, then dynamically create a CSS media query to hide the footer when the height of the window shrinks by 10 pixels. Because opening the keyboard resizes the browser display, this never fails on iOS. Because it's using the CSS engine rather than JavaScript, it's much faster and smoother too!
Note: I found using 'visibility:hidden' less glitchy than 'display:none' or 'position:static', but your mileage may vary.
Works for me
if (navigator.userAgent.match(/iPhone|iPad|iPod/i)) {
$(document).on('focus', 'input, textarea', function() {
$('header').css({'position':'static'});
});
$(document).on('blur', 'input, textarea', function() {
$('header').css({'position':'fixed'});
});
}
In our case this would fix itself as soon as user scrolls. So this is the fix we've been using to simulate a scroll on blur on any input or textarea:
$(document).on('blur', 'input, textarea', function () {
setTimeout(function () {
window.scrollTo(document.body.scrollLeft, document.body.scrollTop);
}, 0);
});
My answer is that it can't be done.
I see 25 answers but none work in my case. That's why Yahoo and other pages hide the fixed header when the keyboard is on. And Bing turns the whole page non-scrollable (overflow-y: hidden).
The cases discussed above are different, some have issues when scrolling, some on focus or blur. Some have fixed footer, or header. I can't test now each combination, but you might end up realizing that it can't be done in your case.
Found this solution on Github.
https://github.com/Simbul/baker/issues/504#issuecomment-12821392
Make sure you have scrollable content.
// put in your .js file
$(window).load(function(){
window.scrollTo(0, 1);
});
// min-height set for scrollable content
<div id="wrap" style="min-height: 480px">
// website goes here
</div>
The address bar folds up as an added bonus.
In case anyone wanted to try this. I got the following working for me on a fixed footer with an inputfield in it.
<script>
$('document').ready(
function() {
if (navigator.userAgent.match(/Android/i) || navigator.userAgent.match(/webOS/i) || navigator.userAgent.match(/iPhone/i) || navigator.userAgent.match(/iPad/i)
|| navigator.userAgent.match(/iPod/i) || navigator.userAgent.match(/BlackBerry/i) || navigator.userAgent.match(/Windows Phone/i)) {
var windowHeight = $(window).height();
var documentHeight = $(document).height();
$('#notes').live('focus', function() {
if (documentHeight > windowHeight) {
$('#controlsContainer').css({
position : 'absolute'
});
$("html, body").animate({
scrollTop : $(document).height()
}, 1);
}
});
$('#notes').live('blur', function() {
$('#controlsContainer').css({
position : 'fixed'
});
$("html, body").animate({
scrollTop : 0
}, 1);
});
}
});
</script>
I have the same issue. But I realized that the fixed position is just delayed and not broken (at least for me). Wait 5-10 seconds and see if the div adjusts back to the bottom of the screen. I believe it's not an error but a delayed response when the keyboard is open.
I tried all the approaches from this thread, but if they didn't help, they did even worse.
In the end, I decided force device to loose focus:
$(<selector to your input field>).focus(function(){
var $this = $(this);
if (<user agent target check>) {
function removeFocus () {
$(<selector to some different interactive element>).focus();
$(window).off('resize', removeFocus);
}
$(window).on('resize', removeFocus);
}
});
and it worked like a charm and fixed my sticky login-form.
Please NOTE:
The JS code above is only to present my idea, to execute this snippet please replace values in angular braces (<>) with appropriate values for your situation.
This code is designed to work with jQuery v1.10.2
This is still a large bug for for any HTML pages with taller Bootstrap Modals in iOS 8.3. None of the proposed solutions above worked and after zooming in on any field below the fold of a tall modal, Mobile Safari and/or WkWebView would move the fixed elements to where the HTML body's scroll was situated, leaving them misaligned with where they actually where laid out.
To workaround the bug, add an event listener to any of your modal inputs like:
$(select.modal).blur(function(){
$('body').scrollTop(0);
});
I'm guessing this works because forcing the HTML body's scroll height re-aligns the actual view with where the iOS 8 WebView expects the fixed modal div's contents to be.
If anybody was looking for a completely different route (like you are not even looking to pin this "footer" div as you scroll but you just want the div to stay at the bottom of the page), you can just set the footer position as relative.
That means that even if the virtual keyboard comes up on your mobile browser, your footer will just stay anchored to the bottom of the page, not trying to react to virtual keyboard show or close.
Obviously it looks better on Safari if position is fixed and the footer follows the page as you scroll up or down but due to this weird bug on Chrome, we ended up switching over to just making the footer relative.
None of the scrolling solutions seemed to work for me. Instead, what worked is to set the position of the body to fixed while the user is editing text and then restore it to static when the user is done. This keeps safari from scrolling your content on you. You can do this either on focus/blur of the element(s) (shown below for a single element but could be for all input, textareas), or if a user is doing something to begin editing like opening a modal, you can do it on that action (e.g. modal open/close).
$("#myInput").on("focus", function () {
$("body").css("position", "fixed");
});
$("#myInput").on("blur", function () {
$("body").css("position", "static");
});
iOS9 - same problem.
TLDR - source of the problem. For solution, scroll to bottom
I had a form in a position:fixed iframe with id='subscribe-popup-frame'
As per the original question, on input focus the iframe would go to the top of the document as opposed to the top of the screen.
The same problem did not occur in safari dev mode with user agent set to an idevice. So it seems the problem is caused by iOS virtual keyboard when it pops up.
I got some visibility into what was happening by console logging the iframe's position (e.g. $('#subscribe-popup-frame', window.parent.document).position() ) and from there I could see iOS seemed to be setting the position of the element to {top: -x, left: 0} when the virtual keyboard popped up (i.e. focussed on the input element).
So my solution was to take that pesky -x, reverse the sign and then use jQuery to add that top position back to the iframe. If there is a better solution I would love to hear it but after trying a dozen different approaches it was the only one that worked for me.
Drawback: I needed to set a timeout of 500ms (maybe less would work but I wanted to be safe) to make sure I captured the final x value after iOS had done its mischief with the position of the element. As a result, the experience is very jerky . . . but at least it works
Solution
var mobileInputReposition = function(){
//if statement is optional, I wanted to restrict this script to mobile devices where the problem arose
if(screen.width < 769){
setTimeout(function(){
var parentFrame = $('#subscribe-popup-frame',window.parent.document);
var parentFramePosFull = parentFrame.position();
var parentFramePosFlip = parentFramePosFull['top'] * -1;
parentFrame.css({'position' : 'fixed', 'top' : parentFramePosFlip + 'px'});
},500);
}
}
Then just call mobileInputReposition in something like $('your-input-field).focus(function(){}) and $('your-input-field).blur(function(){})

Mobile Safari: Disable scrolling pages "out of screen"

I want to block scrolling page "out of the iPhone screen" (when gray Safari's background behind the page border is visible). To do this, I'm cancelling touchmove event:
// Disables scrolling the page out of the screen.
function DisableTouchScrolling()
{
document.addEventListener("touchmove", function TouchHandler(e) { e.preventDefault(); }, true);
}
Unfortunately, this also disables mousemove event: when I tap on a button then move my finger out of it, then release the screen, the button's onclick event is triggered anyway.
I've tried mapping touch events on mouse events, as desribed here: http://ross.posterous.com/2008/08/19/iphone-touch-events-in-javascript/, but to no avail (the same behavior).
Any ideas?
From what I understand of your question, you've attempted to combine the code you've presented above with the code snippet provided by Ross Boucher on Posterous. Attempting to combine these two snippets back-to-back won't work, because in disabling touchmove, you've also disabled the shim that allows mousemove to work via his sample.
This question and its answers sketch out a workable solution to your problem. You should try these two snippets to see if they resolve your issue:
This snippet, which disables the old scrolling behavior:
elementYouWantToScroll.ontouchmove = function(e) {
e.stopPropagation();
};
Or this one, from the same:
document.ontouchmove = function(e) {
var target = e.currentTarget;
while(target) {
if(checkIfElementShouldScroll(target))
return;
target = target.parentNode;
}
e.preventDefault();
};
Then, drop in the code on Posterous:
function touchHandler(event)
{
var touches = event.changedTouches,
first = touches[0],
type = "";
switch(event.type)
{
case "touchstart": type = "mousedown"; break;
case "touchmove": type="mousemove"; break;
case "touchend": type="mouseup"; break;
default: return;
}
//initMouseEvent(type, canBubble, cancelable, view, clickCount,
// screenX, screenY, clientX, clientY, ctrlKey,
// altKey, shiftKey, metaKey, button, relatedTarget);
var simulatedEvent = document.createEvent("MouseEvent");
simulatedEvent.initMouseEvent(type, true, true, window, 1,
first.screenX, first.screenY,
first.clientX, first.clientY, false,
false, false, false, 0/*left*/, null);
first.target.dispatchEvent(simulatedEvent);
event.preventDefault();
}
And that should do it for you. If it doesn't, something else isn't working with Mobile Safari.
Unfortunately I haven't had the time to check out to above yet but was working on an identical problem and found that the nesting of elements in the DOM and which relation you apply it to affects the handler a lot (guess the above solves that, too - 'var target = e.currentTarget').
I used a slightly different approach (I'd love feedback on) by basically using a class "locked" that I assign to every element which (including all its children) i don't want the site to scroll when someone touchmoves on it.
E.g. in HTML:
<header class="locked">...</header>
<div id="content">...</div>
<footer class="locked"></div>
Then I have an event-listener running on that class (excuse my lazy jquery-selector):
$('.ubq_locked').on('touchmove', function(e) {
e.preventDefault();
});
This works pretty well for me on iOs and Android and at least gives me the control to not attach the listener to an element which I know causes problems. You do need to watch your z-index values by the way.
Plus I only attach the listener if it is a touch-device, e.g. like this:
function has_touch() {
var isTouchPad = (/hp-tablet/gi).test(navigator.appVersion);
return 'ontouchstart' in window && !isTouchPad;
}
This way non-touch devices will not be affected.
If you don't want to spam your HTML you could of course just write the selectors into an array and run through those ontouchmove, but I would expect that to be more costly in terms of performance (my knowledge there is limited though). Hope this can help.