I'm developing an app with Angular and Semantic-UI. The app should be accessible, this means it should be compliant with WCAG 2.0.
To reach this purpose the modals should keep focus within the dialog and prevents users from going outside or move with "tabs" between elements of the page that lays under the modal.
I have found some working examples, like the following:
JQuery dialog: https://jqueryui.com/dialog/#modal-confirmation
dialog HTML 5.1 element: https://demo.agektmr.com/dialog
ARIA modal dialog example:
http://w3c.github.io/aria-practices/examples/dialog-modal/dialog.html
(that I have reproduced on Plunker)
Here is my try to create an accessible modal with Semantic-UI: https://plnkr.co/edit/HjhkZg
As you can see I used the following attributes:
role="dialog"
aria-labelledby="modal-title"
aria-modal="true"
But they don't solve my issue. Do you know any way to make my modal keeping focus and lose it only when user click on cancel/confirm buttons?
There is currently no easy way to achieve this. The inert attribute was proposed to try to solve this problem by making any element with the attribute and all of it's children inaccessible. However, adoption has been slow and only recently did it land in Chrome Canary behind a flag.
Another proposed solution is making a native API that would keep track of the modal stack, essentially making everything not currently the top of the stack inert. I'm not sure the status of the proposal, but it doesn't look like it will be implemented any time soon.
So where does that leave us?
Unfortunately without a good solution. One solution that is popular is to create a query selector of all known focusable elements and then trap focus to the modal by adding a keydown event to the last and first elements in the modal. However, with the rise of web components and shadow DOM, this solution can no longer find all focusable elements.
If you always control all the elements within the dialog (and you're not creating a generic dialog library), then probably the easiest way to go is to add an event listener for keydown on the first and last focusable elements, check if tab or shift tab was used, and then focus the first or last element to trap focus.
If you're creating a generic dialog library, the only thing I have found that works reasonably well is to either use the inert polyfill or make everything outside of the modal have a tabindex=-1.
var nonModalNodes;
function openDialog() {
var modalNodes = Array.from( document.querySelectorAll('dialog *') );
// by only finding elements that do not have tabindex="-1" we ensure we don't
// corrupt the previous state of the element if a modal was already open
nonModalNodes = document.querySelectorAll('body *:not(dialog):not([tabindex="-1"])');
for (var i = 0; i < nonModalNodes.length; i++) {
var node = nonModalNodes[i];
if (!modalNodes.includes(node)) {
// save the previous tabindex state so we can restore it on close
node._prevTabindex = node.getAttribute('tabindex');
node.setAttribute('tabindex', -1);
// tabindex=-1 does not prevent the mouse from focusing the node (which
// would show a focus outline around the element). prevent this by disabling
// outline styles while the modal is open
// #see https://www.sitepoint.com/when-do-elements-take-the-focus/
node.style.outline = 'none';
}
}
}
function closeDialog() {
// close the modal and restore tabindex
if (this.type === 'modal') {
document.body.style.overflow = null;
// restore or remove tabindex from nodes
for (var i = 0; i < nonModalNodes.length; i++) {
var node = nonModalNodes[i];
if (node._prevTabindex) {
node.setAttribute('tabindex', node._prevTabindex);
node._prevTabindex = null;
}
else {
node.removeAttribute('tabindex');
}
node.style.outline = null;
}
}
}
The different "working examples" do not work as expected with a screenreader.
They do not trap the screenreader visual focus inside the modal.
For this to work, you have to :
Set the aria-hidden attribute on any other nodes
disable keyboard focusable elements inside those trees (links using tabindex=-1, controls using disabled, ...)
The jQuery :focusable pseudo selector can be useful to find focusable elements.
add a transparent layer over the page to disable mouse selection.
or you can use the css pointer-events: none property when the browser handles it with non SVG elements, not in IE
This focus-trap plugin is excellent at making sure that focus stays trapped inside of dialogue elements.
It sounds like your problem can be broken down into 2 categories:
focus on dialog box
Add a tabindex of -1 to the main container which is the DOM element that has role="dialog". Set the focus to the container.
wrapping the tab key
I found no other way of doing this except by getting the tabbable elements within the dialog box and listening it on keydown. When I know the element in focus (document.activeElement) is the last one on the list, I make it wrap
"focus" events can be intercepted in the capture phase, so you can listen for them at the document.body level, squelch them before they reach the target element, and redirect focus back to a control in your modal dialog. This example assumes a modal dialog with an input element gets displayed and assigned to the variable currDialog:
document.body.addEventListener("focus", (event) => {
if (currDialog && !currDialog.contains(event.target)) {
event.preventDefault();
event.stopPropagation();
currDialog.querySelector("input").focus();
}
}, {capture: true});
You may also want to contain such a dialog in a fixed-position, clear (or low-opacity) backdrop element that takes up the full screen in order to capture and suppress mouse/pointer events, so that no browser feedback (hover, etc.) occurs that could give the user the impression that the background is active.
Don't use any solution requiring you to look up "tabbable" elements. Instead, use keydown and either click events or a backdrop in an effective manor.
(Angular1)
See Asheesh Kumar's answer at https://stackoverflow.com/a/31292097/1754995 for something similar to what I am going for below.
(Angular2-x, I haven't done Angular1 in a while)
Say you have 3 components: BackdropComponent, ModalComponent (has an input), and AppComponent (has an input, the BackdropComponent, and the ModalComponent). You display BackdropComponent and ModalComponent with the correct z-index, both are currently displayed/visible.
What you need to do is have a general window.keydown event with preventDefault() to stop all tabbing when the backdrop/modal component is displayed. I recommend you put that on a BackdropComponent. Then you need a keydown.tab event with stopPropagation() to handle tabbing for the ModalComponent. Both the window.keydown and keydown.tab could probably be in the ModalComponent but there is purpose in a BackdropComponent further than just modals.
This should prevent clicking and tabbing to the AppComponent input and only click or tab to the ModalComponent input [and browser stuffs] when the modal is shown.
If you don't want to use a backdrop to prevent clicking, you can use use click events similarly to the keydown events described above.
Backdrop Component:
#Component({
selector: 'my-backdrop',
host: {
'tabindex': '-1',
'(window:keydown)': 'preventTabbing($event)'
},
...
})
export class BackdropComponent {
...
private preventTabbing(event: KeyboardEvent) {
if (event.keyCode === 9) { // && backdrop shown?
event.preventDefault();
}
}
...
}
Modal Component:
#Component({
selector: 'my-modal',
host: {
'tabindex': '-1',
'(keydown.tab)': 'onTab($event)'
},
...
})
export class ModalComponent {
...
private onTab(event: KeyboardEvent) {
event.stopPropagation();
}
...
}
Here's my solution. It traps Tab or Shift+Tab as necessary on first/last element of modal dialog (in my case found with role="dialog"). Eligible elements being checked are all visible input controls whose HTML may be input,select,textarea,button.
$(document).on('keydown', function(e) {
var target = e.target;
var shiftPressed = e.shiftKey;
// If TAB key pressed
if (e.keyCode == 9) {
// If inside a Modal dialog (determined by attribute role="dialog")
if ($(target).parents('[role=dialog]').length) {
// Find first or last input element in the dialog parent (depending on whether Shift was pressed).
// Input elements must be visible, and can be Input/Select/Button/Textarea.
var borderElem = shiftPressed ?
$(target).closest('[role=dialog]').find('input:visible,select:visible,button:visible,textarea:visible').first()
:
$(target).closest('[role=dialog]').find('input:visible,select:visible,button:visible,textarea:visible').last();
if ($(borderElem).length) {
if ($(target).is($(borderElem))) {
return false;
} else {
return true;
}
}
}
}
return true;
});
we can use the focus trap npm package.
npm i focus-trap
This might help someone who is looking for solution in Angular.
Step 1: Add keydown event on dialog component
#HostListener('document:keydown', ['$event'])
handleTabKeyWInModel(event: any) {
this.sharedService.handleTabKeyWInModel(event, '#modal_id', this.elementRef.nativeElement, 'input,button,select,textarea,a,[tabindex]:not([tabindex="-1"])');
}
This will filters the elements which are preseneted in the Modal dialog.
Step 2: Add common method to handle focus in shared service (or you can add it in your component as well)
handleTabKeyWInModel(e, modelId: string, nativeElement, tagsList: string) {
if (e.keyCode === 9) {
const focusable = nativeElement.querySelector(modelId).querySelectorAll(tagsList);
if (focusable.length) {
const first = focusable[0];
const last = focusable[focusable.length - 1];
const shift = e.shiftKey;
if (shift) {
if (e.target === first) { // shift-tab pressed on first input in dialog
last.focus();
e.preventDefault();
}
} else {
if (e.target === last) { // tab pressed on last input in dialog
first.focus();
e.preventDefault();
}
}
}
}
}
Now this method will take the modal dialog native element and start evaluate on every tab key. Finally we will filter the event on first and last so that we can focus on appropriate elements (on first after last element tab click and on last shift+tab event on first element).
Happy Coding.. :)
I used one of the methods suggested by Steven Lambert, namely, listening to keydown events and intercepting "tab" and "shift+tab" keys. Here's my sample code (Angular 5):
import { Directive, ElementRef, Attribute, HostListener, OnInit } from '#angular/core';
/**
* This directive allows to override default tab order for page controls.
* Particularly useful for working around the modal dialog TAB issue
* (when tab key allows to move focus outside of dialog).
*
* Usage: add "custom-taborder" and "tab-next='next_control'"/"tab-prev='prev_control'" attributes
* to the first and last controls of the dialog.
*
* For example, the first control is <input type="text" name="ctlName">
* and the last one is <button type="submit" name="btnOk">
*
* You should modify the above declarations as follows:
* <input type="text" name="ctlName" custom-taborder tab-prev="btnOk">
* <button type="submit" name="btnOk" custom-taborder tab-next="ctlName">
*/
#Directive({
selector: '[custom-taborder]'
})
export class CustomTabOrderDirective {
private elem: HTMLInputElement;
private nextElemName: string;
private prevElemName: string;
private nextElem: HTMLElement;
private prevElem: HTMLElement;
constructor(
private elemRef: ElementRef
, #Attribute('tab-next') public tabNext: string
, #Attribute('tab-prev') public tabPrev: string
) {
this.elem = this.elemRef.nativeElement;
this.nextElemName = tabNext;
this.prevElemName = tabPrev;
}
ngOnInit() {
if (this.nextElemName) {
var elems = document.getElementsByName(this.nextElemName);
if (elems && elems.length && elems.length > 0)
this.nextElem = elems[0];
}
if (this.prevElemName) {
var elems = document.getElementsByName(this.prevElemName);
if (elems && elems.length && elems.length > 0)
this.prevElem = elems[0];
}
}
#HostListener('keydown', ['$event'])
onKeyDown(event: KeyboardEvent) {
if (event.key !== "Tab")
return;
if (!event.shiftKey && this.nextElem) {
this.nextElem.focus();
event.preventDefault();
}
if (event.shiftKey && this.prevElem) {
this.prevElem.focus();
event.preventDefault();
}
}
}
To use this directive, just import it to your module and add to Declarations section.
I've been successful using Angular Material's A11yModule.
Using your favorite package manager install these to packages into your Angular app.
**"#angular/material": "^10.1.2"**
**"#angular/cdk": "^10.1.2"**
In your Angular module where you import the Angular Material modules add this:
**import {A11yModule} from '#angular/cdk/a11y';**
In your component HTML apply the cdkTrapFocus directive to any parent element, example: div, form, etc.
Run the app, tabbing will now be contained within the decorated parent element.
For jquery users:
Assign role="dialog" to your modal
Find first and last interactive element inside the dialog modal.
Check if current target is one of them(depending on shift key is
pressed or not).
If target element is one of first or last interactive element of the
dialog, return false
Working code sample:
//on keydown inside dialog
$('.modal[role=dialog]').on('keydown', e => {
let target = e.target;
let shiftPressed = e.shiftKey;
// If TAB is pressed
if (e.keyCode === 9) {
// Find first and last element in the ,modal-dialog parent.
// Elements must be interactive i.e. visible, and can be Input/Select/Button/Textarea.
let first = $(target).closest('[role=dialog]').find('input:visible,select:visible,button:visible,textarea:visible').first();
let last = $(target).closest('[role=dialog]').find('input:visible,select:visible,button:visible,textarea:visible').last();
let borderElem = shiftPressed ? first : last //border element on the basis of shift key pressed
if ($(borderElem).length) {
return !$(target).is($(borderElem)); //if target is border element , return false
}
}
return true;
});
I read through most of the answers, while the package focus-trap seems like a good option. #BenVida shared a very simple VanillaJS solution here in another Stack Overflow post.
Here is the code:
const container=document.querySelector("_selector_for_the_container_")
//optional: needed only if the container element is not focusable already
container.setAttribute("tabindex","0")
container.addEventListener("focusout", (ev)=>{
if (!container.contains(ev.relatedTarget)) container.focus()
})
I have a ModalWindow which has a form, which has a TabbedPanel, which has two AbstractTabs which, on which there is a DataTable on each of them, with input elements.
So: ModalWindow > Form > TabbedPanel --> Tab1 (Panel) > DataTable (there are two tabs)
Within the ModalWindow, I added to the form 3 buttons, like the following:
// save button
final GbAjaxButton save = new GbAjaxButton("save") {
private static final long serialVersionUID = 1L;
#Override
public void onSubmit(final AjaxRequestTarget target, final Form<?> form) {
System.out.println("Saving something... ");
}
};
I can see the data being sent via POST to the backend, but I can't seem to be able to access any of the fields in the DataTables.
Some parts for the code are:
tabA = new AbstractTab("Tab Name") {
public Panel getPanel() {
return new SomeNewPanel(panelId,<somedata>); // <-- this has the DataTable with inputs
}
}
Form form = new Form("formNameInHtml");
form.add(new TabbedPanel("htmlName", tabs);
I would really appreciate some insight on this problem.
Thanks.
From ModalWindow javadoc, "If you want to use form in modal window component make sure that you put the modal window itself in another form (nesting forms is legal in Wicket) and that the form on modal window is submitted before the window get closed."
Wicket automatically adds a form outside the modal window, so if you want to use a second form inside you should override org.apache.wicket.markup.html.form.Form#isRootForm() and have it return true.
When a TinyMCE editor blur occurs, I am trying to find the element id (or name) of the textarea which fired the blur event. I also want the element id (or name) of the element which gains the focus, but that part should be similar.
I'm getting closer in being able to get the iframe id of the tinymce editor, but I've only got it working in Chrome and I'm sure there is a better way of doing it. I need this to work across different browsers and devices.
For example, this below code returns the iframe id in Chrome which is okay since the iframe id only appends a suffix of "_ifr" to my textarea element id. I would prefer the element id of the textarea, but it's okay if I need to remove the iframe suffix.
EDIT: I think it's more clear if I add a complete TinyMCE Fiddle (instead of the code below):
http://fiddle.tinymce.com/HIeaab/1
setup : function(ed) {
ed.onInit.add(function(ed) {
ed.pasteAsPlainText = true;
/* BEGIN: Added this to handle JS blur event */
/* example modified from: http://tehhosh.blogspot.com/2012/06/setting-focus-and-blur-event-for.html */
var dom = ed.dom,
doc = ed.getDoc(),
el = doc.content_editable ? ed.getBody() : (tinymce.isGecko ? doc : ed.getWin());
tinymce.dom.Event.add(el, 'blur', function(e) {
//console.log('blur');
var event = e || window.event;
var target = event.target || event.srcElement;
console.log(event);
console.log(target);
console.log(target.frameElement.id);
console.log('the above outputs the following iframe id which triggered the blur (but only in Chrome): ' + 'idPrimeraVista_ifr');
})
tinymce.dom.Event.add(el, 'focus', function(e) {
//console.log('focus');
})
/* END: Added this to handle JS blur event */
});
}
Maybe it's better to give a background of what I'm trying to accomplish:
We have multiple textareas on a form which we're trying to "grammarcheck" with software called "languagetool" (that uses TinyMCE version 3.5.6). Upon losing focus on a textarea, we would like to invoke the grammarcheck for the textarea that lost focus and then return the focus to where it's supposed to go after the grammar check.
I've struggled with this for quite some time, and would greatly appreciate any feedback (even if it's general advice for doing this differently).
Many Thanks!
Simplify
TinyMCE provides a property on the Editor object for getting the editor instance ID: Editor.id
It also seems overkill to check for doc.content_editable and tinyMCE.isGecko because Editor.getBody() allows for cross-browser compatible event binding already (I checked IE8-11, and latest versions of Firefox and Chrome).
Note: I actually found that the logic was failing to properly assign ed.getBody() to el in Internet Explorer, so it wasn't achieving the cross-browser functionality you need anyway.
Try the following simplified event bindings:
tinyMCE.init({
mode : "textareas",
setup : function (ed) {
ed.onInit.add(function (ed) {
/* onBlur */
tinymce.dom.Event.add(ed.getBody(), 'blur', function (e) {
console.log('Editor with ID "' + ed.id + '" has blur.');
});
/* onFocus */
tinymce.dom.Event.add(ed.getBody(), 'focus', function (e) {
console.log('Editor with ID "' + ed.id + '" has focus.');
});
});
}
});
…or see this working TinyMCE Fiddle »
Aside: Your Fiddle wasn't properly initializing the editors because the plugin was failing to load. Since you don't need the plugin for this example, I removed it from the Fiddle to get it working.
I am working on Netbeans building a JavaFX application.
I started using ControlsFX (http://fxexperience.com/controlsfx/)
I have implemented a simple Dialog that uses custom AbstractDialogAction s as I want specific number of buttons to appear.
I do this like this:
Action a = new AbstractDialogAction(" button a ", Dialog.ActionTrait.CLOSING) {
#Override
public void execute(ActionEvent ae) {
}
};
ArrayList<Action> actions = new ArrayList<>();
actions.add(a);
actions.add(b); // other button
actions.add(c); // another button
dialog.actions(actions);
Action response = dialog.showConfirm();
Dialog is shown correctly with the given buttons.
My question is how to force the Dialog to close when a button is pressed ?
I thought setting a Dialog.ActionTrait.CLOSING would do the trick, but the Dialog stays open.
From eugener in ControlsFX mailing list
public void execute(ActionEvent ae) {
if (ae.getSource() instanceof Dialog ) {
((Dialog) ae.getSource()).setResult(this);
}
}
The above sets the result of the Dialog to be the current Action and closes the Dialog
But maybe that is a little redundant as I can simply call:
((Dialog) ae.getSource()).hide();
.hide() hides the Dialog and also sets the current action as the result.
I can't suggest which is a better solution (hide() was suggested by jewelsea)
In addition I would suggest to always override the toString() method of class AbstractDialogAction, in order to get readable result from:
Action response = dialog.showConfirm();
System.out.println("RESPONSE = "+ response.toString());
Hide the dialog to close it => dialog.hide()
I have a tabpanel with 3 tabs. One of the tabs has a table which draws a table with data from the database. But if new data is entered, after I select the tab I have to refresh the browser page to see the update.
I've added the following selection handler to the tabpanel:
tabpanel.addSelectionHandler(new SelectionHandler<Integer>()
{
public void onSelection(SelectionEvent<Integer> event)
{
int tabId = event.getSelectedItem();
Widget tabWidget = tabpanel.getWidget(tabId);
if (tabWidget != null)
{
//assumming that code to refresh will go here...
}
}
});
What can I do so that when a certain tab is selected then that tab will refresh?
Thanks so much in advance.
What you have done is correct. Just put your data access code in the commented area. So for example
int tabId = event.getSelectedItem();
// PSEUDO CODE
data = AsyncCallback.getData()
tabPanel.setWidget(tabId, new Widget(data)); // PSEUDO CODE