h5p-php-library/js/h5p-confirmation-dialog.js

400 lines
12 KiB
JavaScript

/*global H5P*/
H5P.ConfirmationDialog = (function (EventDispatcher) {
"use strict";
/**
* Create a confirmation dialog
*
* @param [options] Options for confirmation dialog
* @param [options.instance] Instance that uses confirmation dialog
* @param [options.headerText] Header text
* @param [options.dialogText] Dialog text
* @param [options.cancelText] Cancel dialog button text
* @param [options.confirmText] Confirm dialog button text
* @param [options.hideCancel] Hide cancel button
* @param [options.hideExit] Hide exit button
* @param [options.classes] Extra classes for popup
* @constructor
*/
function ConfirmationDialog(options) {
EventDispatcher.call(this);
var self = this;
// Make sure confirmation dialogs have unique id
H5P.ConfirmationDialog.uniqueId += 1;
var uniqueId = H5P.ConfirmationDialog.uniqueId;
// Default options
options = options || {};
options.headerText = options.headerText || H5P.t('confirmDialogHeader');
options.dialogText = options.dialogText || H5P.t('confirmDialogBody');
options.cancelText = options.cancelText || H5P.t('cancelLabel');
options.confirmText = options.confirmText || H5P.t('confirmLabel');
/**
* Handle confirming event
* @param {Event} e
*/
function dialogConfirmed(e) {
self.hide();
self.trigger('confirmed');
e.preventDefault();
}
/**
* Handle dialog canceled
* @param {Event} e
*/
function dialogCanceled(e) {
self.hide();
self.trigger('canceled');
e.preventDefault();
}
/**
* Flow focus to element
* @param {HTMLElement} element Next element to be focused
* @param {Event} e Original tab event
*/
function flowTo(element, e) {
element.focus();
e.preventDefault();
}
// Offset of exit button
var exitButtonOffset = 2 * 16;
var shadowOffset = 8;
// Determine if we are too large for our container and must resize
var resizeIFrame = false;
// Create background
var popupBackground = document.createElement('div');
popupBackground.classList
.add('h5p-confirmation-dialog-background', 'hidden', 'hiding');
// Create outer popup
var popup = document.createElement('div');
popup.classList.add('h5p-confirmation-dialog-popup', 'hidden');
if (options.classes) {
options.classes.forEach(function (popupClass) {
popup.classList.add(popupClass);
});
}
popup.setAttribute('role', 'dialog');
popup.setAttribute('aria-labelledby', 'h5p-confirmation-dialog-dialog-text-' + uniqueId);
popupBackground.appendChild(popup);
popup.addEventListener('keydown', function (e) {
if (e.which === 27) {// Esc key
// Exit dialog
dialogCanceled(e);
}
});
// Popup header
var header = document.createElement('div');
header.classList.add('h5p-confirmation-dialog-header');
popup.appendChild(header);
// Header text
var headerText = document.createElement('div');
headerText.classList.add('h5p-confirmation-dialog-header-text');
headerText.innerHTML = options.headerText;
header.appendChild(headerText);
// Popup body
var body = document.createElement('div');
body.classList.add('h5p-confirmation-dialog-body');
popup.appendChild(body);
// Popup text
var text = document.createElement('div');
text.classList.add('h5p-confirmation-dialog-text');
text.innerHTML = options.dialogText;
text.id = 'h5p-confirmation-dialog-dialog-text-' + uniqueId;
body.appendChild(text);
// Popup buttons
var buttons = document.createElement('div');
buttons.classList.add('h5p-confirmation-dialog-buttons');
body.appendChild(buttons);
// Cancel button
var cancelButton = document.createElement('button');
cancelButton.classList.add('h5p-core-cancel-button');
cancelButton.textContent = options.cancelText;
// Confirm button
var confirmButton = document.createElement('button');
confirmButton.classList.add('h5p-core-button');
confirmButton.classList.add('h5p-confirmation-dialog-confirm-button');
confirmButton.textContent = options.confirmText;
// Exit button
var exitButton = document.createElement('button');
exitButton.classList.add('h5p-confirmation-dialog-exit');
exitButton.setAttribute('aria-hidden', 'true');
exitButton.tabIndex = -1;
exitButton.title = options.cancelText;
// Cancel handler
cancelButton.addEventListener('click', dialogCanceled);
cancelButton.addEventListener('keydown', function (e) {
if (e.which === 32) { // Space
dialogCanceled(e);
}
else if (e.which === 9 && e.shiftKey) { // Shift-tab
flowTo(confirmButton, e);
}
});
if (!options.hideCancel) {
buttons.appendChild(cancelButton);
}
else {
// Center buttons
buttons.classList.add('center');
}
// Confirm handler
confirmButton.addEventListener('click', dialogConfirmed);
confirmButton.addEventListener('keydown', function (e) {
if (e.which === 32) { // Space
dialogConfirmed(e);
}
else if (e.which === 9 && !e.shiftKey) { // Tab
const nextButton = !options.hideCancel ? cancelButton : confirmButton;
flowTo(nextButton, e);
}
});
buttons.appendChild(confirmButton);
// Exit handler
exitButton.addEventListener('click', dialogCanceled);
exitButton.addEventListener('keydown', function (e) {
if (e.which === 32) { // Space
dialogCanceled(e);
}
});
if (!options.hideExit) {
popup.appendChild(exitButton);
}
// Wrapper element
var wrapperElement;
// Focus capturing
var focusPredator;
// Maintains hidden state of elements
var wrapperSiblingsHidden = [];
var popupSiblingsHidden = [];
// Element with focus before dialog
var previouslyFocused;
/**
* Set parent of confirmation dialog
* @param {HTMLElement} wrapper
* @returns {H5P.ConfirmationDialog}
*/
this.appendTo = function (wrapper) {
wrapperElement = wrapper;
return this;
};
/**
* Capture the focus element, send it to confirmation button
* @param {Event} e Original focus event
*/
var captureFocus = function (e) {
if (!popupBackground.contains(e.target)) {
e.preventDefault();
confirmButton.focus();
}
};
/**
* Hide siblings of element from assistive technology
*
* @param {HTMLElement} element
* @returns {Array} The previous hidden state of all siblings
*/
var hideSiblings = function (element) {
var hiddenSiblings = [];
var siblings = element.parentNode.children;
var i;
for (i = 0; i < siblings.length; i += 1) {
// Preserve hidden state
hiddenSiblings[i] = siblings[i].getAttribute('aria-hidden') ?
true : false;
if (siblings[i] !== element) {
siblings[i].setAttribute('aria-hidden', true);
}
}
return hiddenSiblings;
};
/**
* Restores assistive technology state of element's siblings
*
* @param {HTMLElement} element
* @param {Array} hiddenSiblings Hidden state of all siblings
*/
var restoreSiblings = function (element, hiddenSiblings) {
var siblings = element.parentNode.children;
var i;
for (i = 0; i < siblings.length; i += 1) {
if (siblings[i] !== element && !hiddenSiblings[i]) {
siblings[i].removeAttribute('aria-hidden');
}
}
};
/**
* Start capturing focus of parent and send it to dialog
*/
var startCapturingFocus = function () {
focusPredator = wrapperElement.parentNode || wrapperElement;
focusPredator.addEventListener('focus', captureFocus, true);
};
/**
* Clean up event listener for capturing focus
*/
var stopCapturingFocus = function () {
focusPredator.removeAttribute('aria-hidden');
focusPredator.removeEventListener('focus', captureFocus, true);
};
/**
* Hide siblings in underlay from assistive technologies
*/
var disableUnderlay = function () {
wrapperSiblingsHidden = hideSiblings(wrapperElement);
popupSiblingsHidden = hideSiblings(popupBackground);
};
/**
* Restore state of underlay for assistive technologies
*/
var restoreUnderlay = function () {
restoreSiblings(wrapperElement, wrapperSiblingsHidden);
restoreSiblings(popupBackground, popupSiblingsHidden);
};
/**
* Fit popup to container. Makes sure it doesn't overflow.
* @params {number} [offsetTop] Offset of popup
*/
var fitToContainer = function (offsetTop) {
var popupOffsetTop = parseInt(popup.style.top, 10);
if (offsetTop !== undefined) {
popupOffsetTop = offsetTop;
}
if (!popupOffsetTop) {
popupOffsetTop = 0;
}
// Overflows height
if (popupOffsetTop + popup.offsetHeight > wrapperElement.offsetHeight) {
popupOffsetTop = wrapperElement.offsetHeight - popup.offsetHeight - shadowOffset;
}
if (popupOffsetTop - exitButtonOffset <= 0) {
popupOffsetTop = exitButtonOffset + shadowOffset;
// We are too big and must resize
resizeIFrame = true;
}
popup.style.top = popupOffsetTop + 'px';
};
/**
* Show confirmation dialog
* @params {number} offsetTop Offset top
* @returns {H5P.ConfirmationDialog}
*/
this.show = function (offsetTop) {
// Capture focused item
previouslyFocused = document.activeElement;
wrapperElement.appendChild(popupBackground);
startCapturingFocus();
disableUnderlay();
popupBackground.classList.remove('hidden');
fitToContainer(offsetTop);
setTimeout(function () {
popup.classList.remove('hidden');
popupBackground.classList.remove('hiding');
setTimeout(function () {
// Focus confirm button
confirmButton.focus();
// Resize iFrame if necessary
if (resizeIFrame && options.instance) {
var minHeight = parseInt(popup.offsetHeight, 10) +
exitButtonOffset + (2 * shadowOffset);
self.setViewPortMinimumHeight(minHeight);
options.instance.trigger('resize');
resizeIFrame = false;
}
}, 100);
}, 0);
return this;
};
/**
* Hide confirmation dialog
* @returns {H5P.ConfirmationDialog}
*/
this.hide = function () {
popupBackground.classList.add('hiding');
popup.classList.add('hidden');
// Restore focus
stopCapturingFocus();
previouslyFocused.focus();
restoreUnderlay();
setTimeout(function () {
popupBackground.classList.add('hidden');
wrapperElement.removeChild(popupBackground);
self.setViewPortMinimumHeight(null);
}, 100);
return this;
};
/**
* Retrieve element
*
* @return {HTMLElement}
*/
this.getElement = function () {
return popup;
};
/**
* Sets the minimum height of the view port
*
* @param {number|null} minHeight
*/
this.setViewPortMinimumHeight = function (minHeight) {
var container = document.querySelector('.h5p-container') || document.body;
container.style.minHeight = (typeof minHeight === 'number') ? (minHeight + 'px') : minHeight;
};
}
ConfirmationDialog.prototype = Object.create(EventDispatcher.prototype);
ConfirmationDialog.prototype.constructor = ConfirmationDialog;
return ConfirmationDialog;
}(H5P.EventDispatcher));
H5P.ConfirmationDialog.uniqueId = -1;