When I want to inspect an element in the browser with either CTRL-SHIFT-C or by clicking , the current focus is changed, possibly leading to elements that was previously visible not being visible any longer.
Is there some way of avoiding that?
You can select the element you need focus on in the Elements panel. Then find the :hov toggle (As of V49 iirc, 48 may still be a thumb-pin icon) which will open a menu for toggling given element states. From there, just select the one you need applied (focus in this case.) That will force the given state even if focus is somewhere else.
Related
I must adapt to application to wcag focus requirements.
My application works on jsf/primefaces and I have problem with focus on many elements.
For example unexpanded filters contains ui-helper-hidden-accessible class (which is invisible until I click filter to expand) and I cant focus on unexpanded filter name to expand it by keyboard because (I think) ui-helper-hidden-accessible which size is 1x1px receive focus.
I want to span element inside filter div or div with ui-selectcheckboxmenu-trigger class will receive focus instead of unexpanded ui-helper-hidden-accessible.
Do You know how to do it?
Second example is primeface's menuItems - they also not receive focus. The only solution I know is to replace the elements to elements without ui-helper-hidden-accessible class, but unfortunately I can't use this soultion
<nf:author id="filter-selected-authors"
value="#{applicationsBean.dataModel.filter.selectedAuthors}"
converter="#{userConverter}"
completeMethod="#{applicationsBean.usersAutoComplete}"
componentsToUpdate=":datatableForm:applicationTable"
dataTableModel="#{applicationsBean.dataModel}"
oncompleteJs="dynamicScroll()"/>
I got some problem when user pressed the TAB-key. There should be a static way in which the user can jump from one form element to the next.
I know there is a posibility to declare in which order the elements should be selected with TabIndex.
Now I would like to know how does the browser decide which element is focused as next Element after pressing Tab.
EDIT: Does it only walk down the dom or does look it on the position on rendered Website, that's what i want to know.
The process of deciding in which order to skip from one focusable element to the next is fairly complex. The first step is to find out, which elements may gain a tab focus.
There is an article by Maks Nemisj that covers your question in length: “Focus, tabIndex and behavior of browsers”.
I'm writing a custom web component that is meant to be interactive. How can I tell the browser that this custom component should receive focus?
I wish that my custom element…
could be focused (by tab-navigation);
could receive keypresses when focused;
could be matched by :focus pseudo-selector.
I'm not using any external library, just plain HTML5 APIs.
Based on this demo that I found in this question, I have this answer:
Just add the tabindex attribute to the elements you want to be focusable.
// Add this to createdCallback function:
if (!this.hasAttribute('tabindex')) {
// Choose one of the following lines (but not both):
this.setAttribute('tabindex', 0);
this.tabIndex = 0;
}
// The browser automatically syncs tabindex attribute with .tabIndex property.
Clicking on the element will give it focus. Pressing tab will work. Using :focus in CSS will also work. keydown and keyup events work, although keypress doesn't (but it's deprecated anyway). Tested on Chrome 44 and Firefox 40.
Also note that this.tabIndex returns -1 even if the HTML attribute is missing, but this has a different behavior than setting tabindex="1":
<foo></foo>: No tabindex attribute, the element is not focusable.
<foo tabindex="-1"></foo>: The element is not reachable through tab-navigation, but it is still focusable by clicking.
References:
http://www.w3.org/TR/html5/editing.html#sequential-focus-navigation-and-the-tabindex-attribute
https://html.spec.whatwg.org/multipage/interaction.html#the-tabindex-attribute
https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/tabindex
https://github.com/whatwg/html/issues/113
#Denilson, I would like to provide you with some more information.
As you said, this.tabIndex = 0 works when your webcomponent contains no focusable elements. If it does, it gets more complicated.
For example, if your component contains one or more inputs, then first the "whole" component gets focus, and only later, when tabbing, each inner inputs get focus, one by one. This is usually not what you want. Usually, when the component gets focus this should mean its first input gets focus immediately.
Also, there is a reverse tabbing problem. If your first input has focus and you press SHIFT-TAB, then the "whole" component gets focus, and you are forced to press SHIFT-TAB twice to move to the previous element.
I found this to solve all focus and tabbing problems:
// At first, the component may get focus and accept tabbing.
createdCallback = function () { this.tabIndex = 0; }
// When the component gets focus, pass focus to the first inner element.
// Then make tabindex -1 so that the component may still get focus, but does NOT accept tabbing.
focus = function (e) { firstFocusableInnerElement.focus(); this.tabIndex = -1; }
// When we completely left the component, then component may accept tabbing again.
blur = function (e) { this.tabIndex = 0; }
Note: As of now (Sep 2015) if an inner element gets focus, then the "whole" element is not matched by the :focus pseudo-selector (tested only in Chrome). If find this behavior to be just plain wrong. The focus event was fired, and the blur event was not. So the element should have focus, right? I hope they change this in the future.
Short answer: delegatesFocus is what you need here, not tabindex.
Details:
Assuming that you have interactive elements inside the shadow DOM, there is no satisfying way to make the component programmatically focusable with tabindex:
if you set it to 0 you add the host element to the tab sequence ("sequential keyboard navigation") and you have an extra tab stop
if you set it to -1 you remove not only the host element but any interactive element inside its shadow DOM from the tab sequence, so the whole thing becomes inaccessible for keyboard users
There's a web component API just for this: ShadowRoot.delegatesFocus, see here. Set this to true and you'll get:
calling .focus() on the host or clicking on any non focusable part of the component focuses the first focusable element in the shadow DOM
:focus styles are applied to the host in addition to the focused element within
tab sequence is unchanged (it should already work the way you want)
It's supported since shadow DOM v1.
One very pragmatic approach I use, if possible and suitable, is just to put a <button type='button'> around my custom element.
This maybe does not fit as solution for you, I mention it anyway for others stepping into this question / problem.
It handles all focus matters, including a focus rectangle an so on.
To tame a <button> is less work than it seems (think especially about the line-height the button changes)
I must have tried a hundred time by now to select an html element and then create a snippet with Chrome SnappySnippet, but each time I get the error
Error! DOM snapshot could not be created. Make sure that you have inspected some element.
In this video it looks easy, but out of those 100 times, I have been able to make it work once with something random.
Question
Is the selection somehow time based, so I have to click on SnappySnippet in e.h. less than a second?
How do you keep the selected element, so when moving the mouse to the SnappySnippet button other elements are not selected from hovering them?
Use the tree-DOM menu, left click on a div so it becomes dark blue. Now it is selected even thought hovering the mouse over other div's it will remain selected.
The problem you have is probably because SnappySnippet can't handle large div's. Try with a very small one first.
I am using a link to jump to the content section of the page. It works fine; however, in IE and Chrome, after the jump if I press Tab it goes back to .
link : Skip to Content
Content Location <a id="anchortext" class='hidden'>Content</a>
Any Idea?
I suspect it has to do with the tab indexes of existing html elements on the page - clicking on an anchor tag as the one you specify above will take you down to the relevant section, but then pressing tab will take you to the first available tab stop (usually a link or form input item), which could very easily be back at the top of the page.
If you refresh the page and press tab once, you'll be taken to the first tab index enabled element of the page - I'm guessing that'll probably be the same section you were being taken to in your original question...
This appears to be a matter of different handling of internal links in browsers, and seems to fall into the category of behavior not defined in specifications, hence browser-dependent.
When you have focused on a link (usually, with tabbing) and hit enter to follow the link, browsers may or may not retain the focus. You can see the difference in behavior by using a CSS rule like :focus { background: yellow; }.
If the focus is retained (which is somewhat illogical, as the focused element may well be out of sight), a tab will take you to the next focusable element on the page (“next” in the sense of tabbing order).
If focus is lost, it may be treated as giving focus to the entire page (an IE oddity), or as having no focus. Either way, hitting tab will take you to the first focusable element on the page (as per the tabbing order).
I’m afraid there’s nothing you can do on a page to change this. It’s between the user and the browser.
AFAIK there's no way of doing that using only html.
So, i made a javascript script using jquery.
When the user clicks on the jump item, i look for the next link or the next link inside a specific element and put a focus on it.
This solves my problem with Chrome (>25) and IE (>7) and of course Firefox does the excelent job of interpret the tab action correctly.
$("#jumpToMenu").on("keydown", function(e) {
var keyCode = e.keyCode || e.which;
if(keyCode == 13) {
e.preventDefault();
e.stopPropagation();
$("#myMenuToJump").find('a:first').focus();
}
}).on("click", function(e) {
e.preventDefault();
e.stopPropagation();
$("#myMenuToJump").find('a:first').focus();
});
Hope this helps...