Sorry if this sounds very obvious but I am new to Ionic 2 / Angular 2. Upon submitting a form, I need to update the button text and click event, ie:
first click on button = submit form + update button text to "Next"
second click on button = trigger goToNext()
I managed to update the button text but not update the click event (to goToNext() ).
.html
<form (ngSubmit)="logForm(i)">
<ion-item>
<ion-input type="text" [(ngModel)]="form.userinput[i]" name="userinput[i]"></ion-input>
</ion-item>
<button ion-button block type="submit" (click)="setNext($event.target, 'Next')">Check</button>
</form>
.ts
setNext(element, text){
element.textContent = 'Next';
}
goToNext(){
// go to Next Page
}
Ideally you change your design a bit to keep a variable that stores state of your 'Controller'. e.g. stores PageNumber. and then behave differently based on what page you are on. So I suggest change design a bit.
But to answer your current question without major change, you can bind the handler dynamically the same way you bind the text. then in the first handler, change the handler for the next click. the default values for handler and text will decide which one is going the be used initially
handler = this.setNext;
text = 'first text';
setNext(){
alert('handler1 called');
this.handler = this.goToNext;
this.text = 'other text';
}
goToNext(){
alert('second called');
// go to Next Page
}
and in your html you go like
<button ion-button block type="submit" (click)="handler()">{{text}}</button>
You can use n00b answer or something like this:
in html file:
<button ion-button block type="submit" (click)="check()">{{btn_txt}}</button>
in ts file:
btn_txt = 'Check';
check() {
if (this.btn_txt == 'Check') {
//do some logic
this.btn_txt = 'Next';
} else {
console.log('go to next page');
}
}
<span id="continue" class="a-button a-button-span12 a-button-primary"><span class="a-button-inner"><input id="continue" tabindex="5" class="a-button-input" type="submit" aria-labelledby="continue-announce"><span id="continue-announce" class="a-button-text" aria-hidden="true">
Continue
</span></span></span>
Above the the HTML from part of a page, which has a 'Continue' button that i'm trying to click, using my script.
So, writing in Javascript, i'm trying to click this button. But nothing I have tried works.
My attempted answer is:
function() {
var goButton = document.getElementById("continue");
goButton.click();},
Why doesn't it work? Help me, please !
You have set the ID of both the span and the input field to "continue". ID's should be unique for a single element. When I enter your code in the browser's console it returns the following:
> var goButton = document.getElementById("continue");
< undefined
> goButton.valueOf()
< <span id="continue" class="a-button a-button-span12 a-button-primary">
You can see the span is the element being selected instead of the input submit button. You should rename either of the 2 elements so both have a unique ID and use that in your script.
Edit: OP mentioned the HTML can not be changed so instead of fixing the use of a not-unique ID this Javascript can be used:
function() {
var continueSpan = document.getElementById("continue");
var goButton = continueSpan.firstElementChild.firstElementChild;
goButton.click();}
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 recently started using the latest Desktop version of Google Material Design Lite, I figured it doesn't have a modal pop up and the team has not yet implemented it for the next release.
I have tried to include bootstrap model into it, but thats not working infect seems pretty messed, I believe with the classes/styles clashing with each others.
Any Idea what will work good as an replacement ??
Thanks for your help.
I was also looking for a similar plugin and then I found mdl-jquery-modal-dialog
https://github.com/oRRs/mdl-jquery-modal-dialog
I used this because the other one I found was having issue on IE11. This one works fine.
<button id="show-info" class="mdl-button mdl-js-button mdl-button--raised mdl-js-ripple-effect mdl-button--accent">
Show Info
</button>
Here a JSFiddle: https://jsfiddle.net/w5cpw7yf/
I came up with a pure JavaScript Solution for this
You can use the default bootstrap data attributes for the buttons, and make sure that your buttons and modals have their own unique IDs.
You need to have Material Design Lite's JS included before using this JavaScript
Check out the code. Any reviews are welcomed. :)
// Selecting all Buttons with data-toggle="modal", i.e. the modal triggers on the page
var modalTriggers = document.querySelectorAll('[data-toggle="modal"]');
// Getting the target modal of every button and applying listeners
for (var i = modalTriggers.length - 1; i >= 0; i--) {
var t = modalTriggers[i].getAttribute('data-target');
var id = '#' + modalTriggers[i].getAttribute('id');
modalProcess(t, id);
}
/**
* It applies the listeners to modal and modal triggers
* #param {string} selector [The Dialog ID]
* #param {string} button [The Dialog triggering Button ID]
*/
function modalProcess(selector, button) {
var dialog = document.querySelector(selector);
var showDialogButton = document.querySelector(button);
if (dialog) {
if (!dialog.showModal) {
dialogPolyfill.registerDialog(dialog);
}
showDialogButton.addEventListener('click', function() {
dialog.showModal();
});
dialog.querySelector('.close').addEventListener('click', function() {
dialog.close();
});
}
}
<!-- Button to trigger Modal-->
<button class="mdl-button mdl-js-button" id="show-dialog" data-toggle="modal" data-target="#upload-pic">
Show Modal
</button>
<!-- Modal -->
<dialog id="upload-pic" class="mdl-dialog mdl-typography--text-center">
<span class="close">×</span>
<h4 class="mdl-dialog__title">Hello World</h4>
<div class="mdl-dialog__content">
<p>This is some content</p>
</div>
</dialog>
I use MDL with bootstrap and the modal is displayed correctly after adding the data-backdrop attribute this to the modal element:
<dialog data-backdrop="false">
Hope it helps!
I am trying to create a chrome extension - when an user clicks on a icon, the popup window with the form appears. The textarea in the form can contain more parameters which comes to URL. After filling in and clicking the GO button, multiple tabs with URLs with this parameters needs to be opened.
Example: popup.html
<form name="myform">`
<textarea id="params" name="params" style="width: 170px;height: 270px;"></textarea>`
<input id="edit" checked="checked" type="radio" name="edit" value="1" /> option 1 <input id="edit" type="radio" name="edit" value="2" /> option 2`
<div id="clicked">GO</div>`
</form>`
Then in popup.js I have:
function click(e) {
chrome.tabs.executeScript(null, {
code: "alert('starting');"
});
opener();
}
document.addEventListener('DOMContentLoaded', function () {
var divs = document.getElementById("red");
divs.addEventListener('click', click);
});
So when an user clicks on GO button, the opener() function needs to be started.
Here is the opener function - it only determines the values of textarea and radio buttons and opens as many new tabs as manz parameters are in the textarea.
function opener() {
alert('working');
var parameter = document.myform.getElementById("params").value;
for (index = 0; index < document.myform.edit.length; index++) {
if (document.myform.edit[index].checked) {
var radioValue = document.myform.edit[index].value;
break;
}
var Result = parameter.split("\n");
if (radioValue == 1) {
for (i = 0; i < Result.length; i++) {
window.open('http://mypage.com?param=' + Result[i]);
}
}
}
}
So the Result is the value of textarea splitted by \n and radio value is the value of radio button selected.
This works fine - after clicking a browser icon the popup with form comes up, but when I fill in the textarea and select the first radiobutton, then I click GO, the opener funvtion works not...
The only thing that works is the popup alert with working word and then the alert starting from the click(e) function.
So the opener function starts, writes the alert, but nothing else... no tabs will open, nothing happens...
Can someone help me please?
I've found that using the chrome.tabs.create function works much better within the extension than the window.open function does.
chrome.tabs.create({url:"https://www.facebook.com/PSChrome"});