I've been trying to programmatically scroll a list (accordion) in an Ionic-Angular app and I’ve been having no success at all.
I reproduced it in this stackblitz: https://stackblitz.com/edit/stack-overflow-ionic-scroll-problem?file=src/app/home/home.page.ts
When you click on an item, it expands and I want it to align to the top of the screen (with the title visible). In this example, I am using scrollIntoView() to get it to the top but it disappears behind the toolbar.
I've tried many things to get it to align properly (including setting a "scroll-margin-top" as suggested on many posts) but this hasn't worked for me.
Also, I can't seem to be able to use the scrollBy() or scrollTo() method... they do nothing at all.
Can anybody help me figure this out and get this precise example to work? Thanks in advance!
The problem is in the property [fullscreen]="true" of the <ion-content> tag.
The property fullscreen of ion-content, according to the ionic documentation...
If true, the content will scroll behind the headers and footers. This effect can easily be seen by setting the toolbar to transparent.
In ionic when you use the option fullscreen as in <ion-content [fullscreen]="true"> it adds the following style to the ion-content tag:
--offset-top: 56px;
The goal of the [fullscreen]="true" is to create the effect of the content scrolling behind the header.
As a side effect, part of the <ion-content> is hidden behind the <ion-header>.
Fullscreen property and scrollIntoView()
According to w3schools...
The scrollIntoView() method scrolls the specified element into the visible area of the browser window.
So, in your code, when you call scrollIntoView() of a group it is working exactly as expected. The screen is scrolled until the top o the group is into the visible area of the browser. The problem is that the <ion-header> is covering part of the top of this visible area.
Solution:
If you remove the [fullscreen]="true" of the <ion-content>tag the scroll will work as you expect.
But you will loose the effect created by the fullscreen property (content scrolling behing the header).
References
Fullscreen property of ion-content tag:
https://ionicframework.com/docs/api/content
ScrollIntoView:
https://www.w3schools.com/JSREF/met_element_scrollintoview.asp
I have run into an issue with the paper-dropdown-menu component, where it's expansion height seems to be limited by an enclosing core-collapse on its containing element. Is there a way to prevent this from occurring? (see images demonstrating symptoms below) Another related side effect seems to be that when the number of items in the dropdown creates a dropdown height that would normally expand below the bottom of the containing collapsible element, it causes the CSS top styling of the dropdown to be overridden, nudging the top of the element higher within the collapsible container element itself while it is expanded. Irregardless of its new top alignment, it still doesn't show the entire list of options as the height of the dropdown itself remains the same. Has anyone run into similar issues? I can post a jsbin, but its a bit convoluted due to me using a custom polymer element that consists of the icon, input control, and an optionally displayed/selectable unit of measure. So before doing that I was hoping someone might recognize this issue right away and be able to point me in the right direction. This is using chrome v38 and the latest paper-dropdown-menu and core-collapse components (bower ^0.4.0)
Unexpanded (note the top alignment):
Expanded (there should be 5 options, but they are being cut off by core-collapse and note the altered top alignment as well):
Proper operation (when dropdown height is same or less than containing collapsible element height):
In core-collapse there is new property 'allowOverflow' to allow collapsible element to overflow when it's opened. This should help paper-dropdown-menu to expand inside core-collapse. The new property is only in core-collapse#master branch and will be available in the next release.
<core-collapse allowOverflow>
<div class="content">
<paper-dropdown-menu>
...
</paper-dropdown-menu>
</div>
</core-collapse>
The new 'layered' attribute of the latest version of paper-dropdown resolves this issue.
I have a div at the top of my mobile application that is position:fixed so it will stay on the top of the browser (it scrolls away in ios 4 and lower which is fine). When an input is focused and brings up the keyboard, the div moves down to the middle of the page. See screenshots:
http://dbanksdesign.com/ftp/photo_2.PNG
Edit:
Here is a simplified test page:
http://dbanksdesign.com/test/
<body>
<div class="fixed"><input type="text" /></div>
<div class="content"></div>
</body>
.fixed { position:fixed; top:0; left:0; width:100%; background:#ccc; }
.content { width:100%; height:1000px; background:#efefef; }
Unfortunately you are probably best off using absolute positioning for your fixed elements when working with IOS. Yes, IOS5 does claim to support fixed positioning, but it all falls down when you have interactive controls within that fixed element.
I had the same problem with the search box on my switchitoff.net site. In IOS5 the fixed header would jump down the page if the search box gained focus while the page was scrolled. I tried various workarounds, and the one I currently have is a <div> which sits over the search box. When this <div> is clicked the following occurs:
The page is scrolled to the top
The fixed header is changed to absolute
The <div> covering the search box is hidden
The search <input> is focused
The above steps are reversed when the search box loses focus. This solution prevents the header jumping down the page when the search box is clicked, but for a simpler site you are probably better using absolute positioning in the first place.
There is another tricky issue with IOS5 and fixed positioning. If you have clickable elements on your fixed area with body elements scrolled behind them, this can break your touch events.
For example, on switchitoff.net the buttons on the fixed header became unclickable when interactive elements were scrolled behind them. touchstart was not even being fired when these buttons where tapped. Luckily onClick still seemed to work, although this is always a last resort for IOS because of the delay.
Finally notice how (in IOS5) you can click on the fixed header and scroll the page. I know this emulates the way you can use the scroll wheel over a fixed header in a normal browser, but surely this paradigm doesn't make sense for a touch-UI?
Hopefully Apple will continue to refine the handling of fixed elements, but in the meantime it's easier to stick with absolute positioning if you have anything interactive in your fixed area. That or go back to IOS4 when things were so much easier!
Using the JohnW recomendation to use absolute instead of fixed I came up with this workaround:
First set up a bind to detect when the input is onFocus, scroll to the top of the page and change the element position to absolute:
$('#textinput').bind('focus',function(e) {
$('html,body').animate({
scrollTop: 0
});
$('#textinput-container').css('position','absolute');
$('#textinput-container').css('top','0px');
});
Note that I'm using the id textinput for the input and textinput-container for the div top bar that is containing the input.
Set up another bind to detect when the input is not on focus anymore to change the position of the div back to fixed
$('#textinput').bind('blur',function(e) {
$('#textinput-container').css('position','fixed');
$('#textinput-container').css('top','0px');
});
I've been using a similar solution for a bar fixed at the bottom of the page, the code posted should be working for a bar fixed at the top but I didn't test it
Modified version of pablobart's solution but without scrolling to top:
// Absolute position
$('#your-field').bind('focus',function(e) {
setTimeout(function(){
$('section#footer').css('position','absolute');
$('section#footer').css('top',($(window).scrollTop() + window.innerHeight) - $('section#footer').height());
}, 100);
});
// Back to fixed position
$('#your-field').bind('focusout',function(e) {
$('section#footer').removeAttr('style');
});
The simple CSS:
section#footer
*{ position:fixed; bottom:0; left:0; height:42px }*
This solution works pretty well for me. All the code does is wait until the user taps on a text field, then changes the element identified by the 'jQuerySelector' parameter from a 'fixed' to 'static' position. When the text field looses focus (the user tapped on something else) the element's position is changed back to 'fixed'.
// toggles the value of 'position' when the text field gains and looses focus
var togglePositionInResponseToInputFocus = function(jQuerySelector)
{
// find the input element in question
var element = jQuery(jQuerySelector);
// if we have the element
if (element) {
// get the current position value
var position = element.css('position');
// toggle the values from fixed to static, and vice versa
if (position == 'fixed') {
element.css('position', 'static');
} else if (position == 'static') {
element.css('position', 'fixed');
}
}
};
And the associated event handlers:
var that = this;
// called when text field gains focus
jQuery(that.textfieldSelector).on
(
'focusin',
function()
{
togglePositionInResponseToInputFocus(that.jQuerySelector);
}
);
// called when text field looses focus
jQuery(that.textfieldSelector).on
(
'focusout',
function()
{
togglePositionInResponseToInputFocus(that.jQuerySelector);
}
);
The reason the buttons are becoming unclickable is because they have actually scrolled invisibly with the content. They are still there, just not at the location they were originally, nor where you see them.
If you can guess how much the button has moved (based on how much the content has moved) you can click on the invisible button and it will function normally. In other words, if the content has scrolled by 50 pixels, click 50 pixels away from the button and it will work.
You can scroll the content manually (even by a tiny amount) and the buttons will again work as expected.
Just hide your fixed element on focus and then show it again on focusout. I bet your users don't need to see it when focused. I know this is not a solution but I think it is a better approach. Keep it simple.
I have a div that has background:transparent, along with border. Underneath this div, I have more elements.
Currently, I'm able to click the underlying elements when I click outside of the overlay div. However, I'm unable to click the underlying elements when clicking directly on the overlay div.
I want to be able to click through this div so that I can click on the underlying elements.
Yes, you CAN do this.
Using pointer-events: none along with CSS conditional statements for IE11 (does not work in IE10 or below), you can get a cross browser compatible solution for this problem.
Using AlphaImageLoader, you can even put transparent .PNG/.GIFs in the overlay div and have clicks flow through to elements underneath.
CSS:
pointer-events: none;
background: url('your_transparent.png');
IE11 conditional:
filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src='your_transparent.png', sizingMethod='scale');
background: none !important;
Here is a basic example page with all the code.
Yes, you CAN force overlapping layers to pass through (ignore) click events.
PLUS you CAN have specific children excluded from this behavior...
You can do this, using pointer-events
pointer-events influences the reaction to click-, tap-, scroll- und hover events.
In a layer that should ignore / pass-through mentioned events you set
pointer-events: none;
Children of that unresponsive layer that need to react mouse / tap events again need:
pointer-events: auto;
That second part is very helpful if you work with multiple overlapping div layers (probably some parents being transparent), where you need to be able to click on child elements and only that child elements.
Example usage:
.parent {
pointer-events:none;
}
.child {
pointer-events:auto;
}
<div class="parent">
I'm unresponsive
I'm clickable again, wohoo !
</div>
Allowing the user to click through a div to the underlying element depends on the browser. All modern browsers, including Firefox, Chrome, Safari, and Opera, understand pointer-events:none.
For IE, it depends on the background. If the background is transparent, clickthrough works without you needing to do anything. On the other hand, for something like background:white; opacity:0; filter:Alpha(opacity=0);, IE needs manual event forwarding.
See a JSFiddle test and CanIUse pointer events.
I'm adding this answer because I didn’t see it here in full. I was able to do this using elementFromPoint. So basically:
attach a click to the div you want to be clicked through
hide it
determine what element the pointer is on
fire the click on the element there.
var range-selector= $("")
.css("position", "absolute").addClass("range-selector")
.appendTo("")
.click(function(e) {
_range-selector.hide();
$(document.elementFromPoint(e.clientX,e.clientY)).trigger("click");
});
In my case the overlaying div is absolutely positioned—I am not sure if this makes a difference. This works on IE8/9, Safari Chrome and Firefox at least.
Hide overlaying the element
Determine cursor coordinates
Get element on those coordinates
Trigger click on element
Show overlaying element again
$('#elementontop').click(e => {
$('#elementontop').hide();
$(document.elementFromPoint(e.clientX, e.clientY)).trigger("click");
$('#elementontop').show();
});
I needed to do this and decided to take this route:
$('.overlay').click(function(e){
var left = $(window).scrollLeft();
var top = $(window).scrollTop();
//hide the overlay for now so the document can find the underlying elements
$(this).css('display','none');
//use the current scroll position to deduct from the click position
$(document.elementFromPoint(e.pageX-left, e.pageY-top)).click();
//show the overlay again
$(this).css('display','block');
});
I currently work with canvas speech balloons. But because the balloon with the pointer is wrapped in a div, some links under it aren't click able anymore. I cant use extjs in this case.
See basic example for my speech balloon tutorial requires HTML5
So I decided to collect all link coordinates from inside the balloons in an array.
var clickarray=[];
function getcoo(thatdiv){
thatdiv.find(".link").each(function(){
var offset=$(this).offset();
clickarray.unshift([(offset.left),
(offset.top),
(offset.left+$(this).width()),
(offset.top+$(this).height()),
($(this).attr('name')),
1]);
});
}
I call this function on each (new) balloon. It grabs the coordinates of the left/top and right/down corners of a link.class - additionally the name attribute for what to do if someone clicks in that coordinates and I loved to set a 1 which means that it wasn't clicked jet. And unshift this array to the clickarray. You could use push too.
To work with that array:
$("body").click(function(event){
event.preventDefault();//if it is a a-tag
var x=event.pageX;
var y=event.pageY;
var job="";
for(var i in clickarray){
if(x>=clickarray[i][0] && x<=clickarray[i][2] && y>=clickarray[i][1] && y<=clickarray[i][3] && clickarray[i][5]==1){
job=clickarray[i][4];
clickarray[i][5]=0;//set to allready clicked
break;
}
}
if(job.length>0){
// --do some thing with the job --
}
});
This function proofs the coordinates of a body click event or whether it was already clicked and returns the name attribute. I think it is not necessary to go deeper, but you see it is not that complicate.
Hope in was enlish...
Another idea to try (situationally) would be to:
Put the content you want in a div;
Put the non-clicking overlay over the entire page with a z-index higher,
make another cropped copy of the original div
overlay and abs position the copy div in the same place as the original content you want to be clickable with an even higher z-index?
Any thoughts?
I think the event.stopPropagation(); should be mentioned here as well. Add this to the Click function of your button.
Prevents the event from bubbling up the DOM tree, preventing any parent handlers from being notified of the event.
Just wrap a tag around all the HTML extract, for example
<a href="/categories/1">
<img alt="test1" class="img-responsive" src="/assets/photo.jpg" />
<div class="caption bg-orange">
<h2>
test1
</h2>
</div>
</a>
in my example my caption class has hover effects, that with pointer-events:none; you just will lose
wrapping the content will keep your hover effects and you can click in all the picture, div included, regards!
An easier way would be to inline the transparent background image using Data URIs as follows:
.click-through {
pointer-events: none;
background: url(data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7);
}
I think that you can consider changing your markup. If I am not wrong, you'd like to put an invisible layer above the document and your invisible markup may be preceding your document image (is this correct?).
Instead, I propose that you put the invisible right after the document image but changing the position to absolute.
Notice that you need a parent element to have position: relative and then you will be able to use this idea. Otherwise your absolute layer will be placed just in the top left corner.
An absolute position element is positioned relative to the first parent
element that has a position other than static.
If no such element is found, the containing block is html
Hope this helps. See here for more information about CSS positioning.
You can place an AP overlay like...
#overlay {
position: absolute;
top: -79px;
left: -60px;
height: 80px;
width: 380px;
z-index: 2;
background: url(fake.gif);
}
<div id="overlay"></div>
just put it over where you dont want ie cliked. Works in all.
This is not a precise answer for the question but may help in finding a workaround for it.
I had an image I was hiding on page load and displaying when waiting on an AJAX call then hiding again however...
I found the only way to display my image when loading the page then make it disappear and be able to click things where the image was located before hiding it was to put the image into a DIV, make the size of the DIV 10x10 pixels or small enough to prevent it causing an issue then hiding the containing div. This allowed the image to overflow the div while visible and when the div was hidden, only the divs area was affected by inability to click objects beneath and not the whole size of the image the DIV contained and was displaying.
I tried all the methods to hide the image including CSS display=none/block, opacity=0, hiding the image with hidden=true. All of them resulted in my image being hidden but the area where it was displayed to act like there was a cover over the stuff underneath so clicks and so on wouldn't act on the underlying objects. Once the image was inside a tiny DIV and I hid the tiny DIV, the entire area occupied by the image was clear and only the tiny area under the DIV I hid was affected but as I made it small enough (10x10 pixels), the issue was fixed (sort of).
I found this to be a dirty workaround for what should be a simple issue but I was not able to find any way to hide the object in its native format without a container. My object was in the form of etc. If anyone has a better way, please let me know.
I couldn't always use pointer-events: none in my scenario, because I wanted both the overlay and the underlying element(s) to be clickable / selectable.
The DOM structure looked like this:
<div id="outerElement">
<div id="canvas-wrapper">
<canvas id="overlay"></canvas>
</div>
<!-- Omitted: element(s) behind canvas that should still be selectable -->
</div>
(The outerElement, canvas-wrapper and canvas elements have the same size.)
To make the elements behind the canvas act normally (e.g. selectable, editable), I used the following code:
canvasWrapper.style.pointerEvents = 'none';
outerElement.addEventListener('mousedown', event => {
const clickedOnElementInCanvas = yourCheck // TODO: check if the event *would* click a canvas element.
if (!clickedOnElementInCanvas) {
// if necessary, add logic to deselect your canvas elements ...
wrapper.style.pointerEvents = 'none';
return true;
}
// Check if we emitted the event ourselves (avoid endless loop)
if (event.isTrusted) {
// Manually forward element to the canvas
const mouseEvent = new MouseEvent(event.type, event);
canvas.dispatchEvent(mouseEvent);
mouseEvent.stopPropagation();
}
return true;
});
Some canvas objects also came with input fields, so I had to allow keyboard events, too.
To do this, I had to update the pointerEvents property based on whether a canvas input field was currently focused or not:
onCanvasModified(canvas, () => {
const inputFieldInCanvasActive = // TODO: Check if an input field of the canvas is active.
wrapper.style.pointerEvents = inputFieldInCanvasActive ? 'auto' : 'none';
});
it doesn't work that way. the work around is to manually check the coordinates of the mouse click against the area occupied by each element.
area occupied by an element can found found by 1. getting the location of the element with respect to the top left of the page, and 2. the width and the height. a library like jQuery makes this pretty simple, although it can be done in plain js. adding an event handler for mousemove on the document object will provide continuous updates of the mouse position from the top and left of the page. deciding if the mouse is over any given object consists of checking if the mouse position is between the left, right, top and bottom edges of an element.
Nope, you can't click ‘through’ an element. You can get the co-ordinates of the click and try to work out what element was underneath the clicked element, but this is really tedious for browsers that don't have document.elementFromPoint. Then you still have to emulate the default action of clicking, which isn't necessarily trivial depending on what elements you have under there.
Since you've got a fully-transparent window area, you'll probably be better off implementing it as separate border elements around the outside, leaving the centre area free of obstruction so you can really just click straight through.