// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Question class for drag and drop marker question type, used to support the question and preview pages.
*
* @module qtype_ddmarker/question
* @copyright 2018 The Open University
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
define([
'jquery',
'core/dragdrop',
'qtype_ddmarker/shapes',
'core/key_codes',
'core_form/changechecker'
], function(
$,
dragDrop,
Shapes,
keys,
FormChangeChecker
) {
"use strict";
/**
* Object to handle one drag-drop markers question.
*
* @param {String} containerId id of the outer div for this question.
* @param {boolean} readOnly whether the question is being displayed read-only.
* @param {Object[]} visibleDropZones the geometry of any drop-zones to show.
* Objects have fields shape, coords and markertext.
* @constructor
*/
function DragDropMarkersQuestion(containerId, readOnly, visibleDropZones) {
var thisQ = this;
this.containerId = containerId;
this.visibleDropZones = visibleDropZones;
this.shapes = [];
this.shapeSVGs = [];
this.isPrinting = false;
this.questionAnswer = {};
if (readOnly) {
this.getRoot().addClass('qtype_ddmarker-readonly');
}
thisQ.cloneDrags();
thisQ.repositionDrags();
thisQ.drawDropzones();
}
/**
* Draws the svg shapes of any drop zones that should be visible for feedback purposes.
*/
DragDropMarkersQuestion.prototype.drawDropzones = function() {
if (this.visibleDropZones.length > 0) {
var bgImage = this.bgImage();
this.getRoot().find('div.dropzones').html('<svg xmlns="http://www.w3.org/2000/svg" class="dropzones" ' +
'width="' + bgImage.outerWidth() + '" ' +
'height="' + bgImage.outerHeight() + '"></svg>');
var svg = this.getRoot().find('svg.dropzones');
var nextColourIndex = 0;
for (var dropZoneNo = 0; dropZoneNo < this.visibleDropZones.length; dropZoneNo++) {
var colourClass = 'color' + nextColourIndex;
nextColourIndex = (nextColourIndex + 1) % 8;
this.addDropzone(svg, dropZoneNo, colourClass);
}
}
};
/**
* Adds a dropzone shape with colour, coords and link provided to the array of shapes.
*
* @param {jQuery} svg the SVG image to which to add this drop zone.
* @param {int} dropZoneNo which drop-zone to add.
* @param {string} colourClass class name
*/
DragDropMarkersQuestion.prototype.addDropzone = function(svg, dropZoneNo, colourClass) {
var dropZone = this.visibleDropZones[dropZoneNo],
shape = Shapes.make(dropZone.shape, ''),
existingmarkertext,
bgRatio = this.bgRatio();
if (!shape.parse(dropZone.coords, bgRatio)) {
return;
}
existingmarkertext = this.getRoot().find('div.markertexts span.markertext' + dropZoneNo);
if (existingmarkertext.length) {
if (dropZone.markertext !== '') {
existingmarkertext.html(dropZone.markertext);
} else {
existingmarkertext.remove();
}
} else if (dropZone.markertext !== '') {
var classnames = 'markertext markertext' + dropZoneNo;
this.getRoot().find('div.markertexts').append('<span class="' + classnames + '">' +
dropZone.markertext + '</span>');
var markerspan = this.getRoot().find('div.ddarea div.markertexts span.markertext' + dropZoneNo);
if (markerspan.length) {
var handles = shape.getHandlePositions();
var positionLeft = handles.moveHandle.x - (markerspan.outerWidth() / 2) - 4;
var positionTop = handles.moveHandle.y - (markerspan.outerHeight() / 2);
markerspan
.css('left', positionLeft)
.css('top', positionTop);
markerspan
.data('originX', markerspan.position().left / bgRatio)
.data('originY', markerspan.position().top / bgRatio);
this.handleElementScale(markerspan, 'center');
}
}
var shapeSVG = shape.makeSvg(svg[0]);
shapeSVG.setAttribute('class', 'dropzone ' + colourClass);
this.shapes[this.shapes.length] = shape;
this.shapeSVGs[this.shapeSVGs.length] = shapeSVG;
};
/**
* Draws the drag items on the page (and drop zones if required).
* The idea is to re-draw all the drags and drops whenever there is a change
* like a widow resize or an item dropped in place.
*/
DragDropMarkersQuestion.prototype.repositionDrags = function() {
var root = this.getRoot(),
thisQ = this;
root.find('div.draghomes .marker').not('.dragplaceholder').each(function(key, item) {
$(item).addClass('unneeded');
});
root.find('input.choices').each(function(key, input) {
var choiceNo = thisQ.getChoiceNoFromElement(input),
coords = thisQ.getCoords(input);
if (coords.length) {
var drag = thisQ.getRoot().find('.draghomes' + ' span.marker' + '.choice' + choiceNo).not('.dragplaceholder');
drag.remove();
for (var i = 0; i < coords.length; i++) {
var dragInDrop = drag.clone();
dragInDrop.data('pagex', coords[i].x).data('pagey', coords[i].y);
// We always save the coordinates in the 1:1 ratio.
// So we need to set the scale ratio to 1 for the initial load.
dragInDrop.data('scaleRatio', 1);
thisQ.sendDragToDrop(dragInDrop, false, true);
}
thisQ.getDragClone(drag).addClass('active');
thisQ.cloneDragIfNeeded(drag);
}
});
// Save the question answer.
thisQ.questionAnswer = thisQ.getQuestionAnsweredValues();
};
/**
* Get the question answered values.
*
* @return {Object} Contain key-value with key is the input id and value is the input value.
*/
DragDropMarkersQuestion.prototype.getQuestionAnsweredValues = function() {
let result = {};
this.getRoot().find('input.choices').each((i, inputNode) => {
result[inputNode.id] = inputNode.value;
});
return result;
};
/**
* Check if the question is being interacted or not.
*
* @return {boolean} Return true if the user has changed the question-answer.
*/
DragDropMarkersQuestion.prototype.isQuestionInteracted = function() {
const oldAnswer = this.questionAnswer;
const newAnswer = this.getQuestionAnsweredValues();
let isInteracted = false;
// First, check both answers have the same structure or not.
if (JSON.stringify(newAnswer) !== JSON.stringify(oldAnswer)) {
isInteracted = true;
return isInteracted;
}
// Check the values.
Object.keys(newAnswer).forEach(key => {
if (newAnswer[key] !== oldAnswer[key]) {
isInteracted = true;
}
});
return isInteracted;
};
/**
* Determine what drag items need to be shown and
* return coords of all drag items except any that are currently being dragged
* based on contents of hidden inputs and whether drags are 'infinite' or how many
* drags should be shown.
*
* @param {jQuery} inputNode
* @returns {Point[]} coordinates of however many copies of the drag item should be shown.
*/
DragDropMarkersQuestion.prototype.getCoords = function(inputNode) {
var coords = [],
val = $(inputNode).val();
if (val !== '') {
var coordsStrings = val.split(';');
for (var i = 0; i < coordsStrings.length; i++) {
coords[i] = this.convertToWindowXY(Shapes.Point.parse(coordsStrings[i]));
}
}
return coords;
};
/**
* Converts the relative x and y position coordinates into
* absolute x and y position coordinates.
*
* @param {Point} point relative to the background image.
* @returns {Point} point relative to the page.
*/
DragDropMarkersQuestion.prototype.convertToWindowXY = function(point) {
var bgImage = this.bgImage();
// The +1 seems rather odd, but seems to give the best results in
// the three main browsers at a range of zoom levels.
// (Its due to the 1px border around the image, that shifts the
// image pixels by 1 down and to the left.)
return point.offset(bgImage.offset().left + 1, bgImage.offset().top + 1);
};
/**
* Utility function converting window coordinates to relative to the
* background image coordinates.
*
* @param {Point} point relative to the page.
* @returns {Point} point relative to the background image.
*/
DragDropMarkersQuestion.prototype.convertToBgImgXY = function(point) {
var bgImage = this.bgImage();
return point.offset(-bgImage.offset().left - 1, -bgImage.offset().top - 1);
};
/**
* Is the point within the background image?
*
* @param {Point} point relative to the BG image.
* @return {boolean} true it they are.
*/
DragDropMarkersQuestion.prototype.coordsInBgImg = function(point) {
var bgImage = this.bgImage();
var bgPosition = bgImage.offset();
return point.x >= bgPosition.left && point.x < bgPosition.left + bgImage.width()
&& point.y >= bgPosition.top && point.y < bgPosition.top + bgImage.height();
};
/**
* Get the outer div for this question.
* @returns {jQuery} containing that div.
*/
DragDropMarkersQuestion.prototype.getRoot = function() {
return $(document.getElementById(this.containerId));
};
/**
* Get the img that is the background image.
* @returns {jQuery} containing that img.
*/
DragDropMarkersQuestion.prototype.bgImage = function() {
return this.getRoot().find('img.dropbackground');
};
DragDropMarkersQuestion.prototype.handleDragStart = function(e) {
var thisQ = this,
dragged = $(e.target).closest('.marker');
var info = dragDrop.prepare(e);
if (!info.start) {
return;
}
dragged.addClass('beingdragged').css('transform', '');
var placed = !dragged.hasClass('unneeded');
if (!placed) {
var hiddenDrag = thisQ.getDragClone(dragged);
if (hiddenDrag.length) {
hiddenDrag.addClass('active');
dragged.offset(hiddenDrag.offset());
}
}
dragDrop.start(e, dragged, function() {
void (1);
}, function(x, y, dragged) {
thisQ.dragEnd(dragged);
});
};
/**
* Functionality at the end of a drag drop.
* @param {jQuery} dragged the marker that was dragged.
*/
DragDropMarkersQuestion.prototype.dragEnd = function(dragged) {
var placed = false,
choiceNo = this.getChoiceNoFromElement(dragged),
bgRatio = this.bgRatio(),
dragXY;
dragged.data('pagex', dragged.offset().left).data('pagey', dragged.offset().top);
dragXY = new Shapes.Point(dragged.data('pagex'), dragged.data('pagey'));
if (this.coordsInBgImg(dragXY)) {
this.sendDragToDrop(dragged, true);
placed = true;
// It seems that the dragdrop sometimes leaves the drag
// one pixel out of position. Put it in exactly the right place.
var bgImgXY = this.convertToBgImgXY(dragXY);
bgImgXY = new Shapes.Point(bgImgXY.x / bgRatio, bgImgXY.y / bgRatio);
dragged.data('originX', bgImgXY.x).data('originY', bgImgXY.y);
}
if (!placed) {
this.sendDragHome(dragged);
this.removeDragIfNeeded(dragged);
} else {
this.cloneDragIfNeeded(dragged);
}
this.saveCoordsForChoice(choiceNo);
};
/**
* Save the coordinates for a dropped item in the form field.
* @param {Number} choiceNo which copy of the choice this was.
*/
DragDropMarkersQuestion.prototype.saveCoordsForChoice = function(choiceNo) {
var coords = [],
items = this.getRoot().find('div.droparea span.marker.choice' + choiceNo),
thiQ = this,
bgRatio = this.bgRatio();
if (items.length) {
items.each(function() {
var drag = $(this);
if (!drag.hasClass('beingdragged')) {
if (drag.data('scaleRatio') !== bgRatio) {
// The scale ratio for the draggable item was changed. We need to update that.
drag.data('pagex', drag.offset().left).data('pagey', drag.offset().top);
}
var dragXY = new Shapes.Point(drag.data('pagex'), drag.data('pagey'));
if (thiQ.coordsInBgImg(dragXY)) {
var bgImgXY = thiQ.convertToBgImgXY(dragXY);
bgImgXY = new Shapes.Point(bgImgXY.x / bgRatio, bgImgXY.y / bgRatio);
coords[coords.length] = bgImgXY;
}
}
});
}
this.getRoot().find('input.choice' + choiceNo).val(coords.join(';'));
if (this.isQuestionInteracted()) {
// The user has interacted with the draggable items. We need to mark the form as dirty.
questionManager.handleFormDirty();
// Save the new answered value.
this.questionAnswer = this.getQuestionAnsweredValues();
}
};
/**
* Handle key down / press events on markers.
* @param {KeyboardEvent} e
*/
DragDropMarkersQuestion.prototype.handleKeyPress = function(e) {
var drag = $(e.target).closest('.marker'),
point = new Shapes.Point(drag.offset().left, drag.offset().top),
choiceNo = this.getChoiceNoFromElement(drag);
switch (e.keyCode) {
case keys.arrowLeft:
case 65: // A.
point.x -= 1;
break;
case keys.arrowRight:
case 68: // D.
point.x += 1;
break;
case keys.arrowDown:
case 83: // S.
point.y += 1;
break;
case keys.arrowUp:
case 87: // W.
point.y -= 1;
break;
case keys.space:
case keys.escape:
point = null;
break;
default:
return; // Ingore other keys.
}
e.preventDefault();
if (point !== null) {
point = this.constrainToBgImg(point);
drag.offset({'left': point.x, 'top': point.y});
drag.data('pagex', drag.offset().left).data('pagey', drag.offset().top);
var dragXY = this.convertToBgImgXY(new Shapes.Point(drag.data('pagex'), drag.data('pagey')));
drag.data('originX', dragXY.x / this.bgRatio()).data('originY', dragXY.y / this.bgRatio());
if (this.coordsInBgImg(new Shapes.Point(drag.offset().left, drag.offset().top))) {
if (drag.hasClass('unneeded')) {
this.sendDragToDrop(drag, true);
var hiddenDrag = this.getDragClone(drag);
if (hiddenDrag.length) {
hiddenDrag.addClass('active');
}
this.cloneDragIfNeeded(drag);
}
}
} else {
drag.css('left', '').css('top', '');
drag.data('pagex', drag.offset().left).data('pagey', drag.offset().top);
this.sendDragHome(drag);
this.removeDragIfNeeded(drag);
}
drag.focus();
this.saveCoordsForChoice(choiceNo);
};
/**
* Makes sure the dragged item always exists within the background image area.
*
* @param {Point} windowxy
* @returns {Point} coordinates
*/
DragDropMarkersQuestion.prototype.constrainToBgImg = function(windowxy) {
var bgImg = this.bgImage(),
bgImgXY = this.convertToBgImgXY(windowxy);
bgImgXY.x = Math.max(0, bgImgXY.x);
bgImgXY.y = Math.max(0, bgImgXY.y);
bgImgXY.x = Math.min(bgImg.width(), bgImgXY.x);
bgImgXY.y = Math.min(bgImg.height(), bgImgXY.y);
return this.convertToWindowXY(bgImgXY);
};
/**
* Returns the choice number for a node.
*
* @param {Element|jQuery} node
* @returns {Number}
*/
DragDropMarkersQuestion.prototype.getChoiceNoFromElement = function(node) {
return Number(this.getClassnameNumericSuffix(node, 'choice'));
};
/**
* Returns the numeric part of a class with the given prefix.
*
* @param {Element|jQuery} node
* @param {String} prefix
* @returns {Number|null}
*/
DragDropMarkersQuestion.prototype.getClassnameNumericSuffix = function(node, prefix) {
var classes = $(node).attr('class');
if (classes !== undefined && classes !== '') {
var classesarr = classes.split(' ');
for (var index = 0; index < classesarr.length; index++) {
var patt1 = new RegExp('^' + prefix + '([0-9])+$');
if (patt1.test(classesarr[index])) {
var patt2 = new RegExp('([0-9])+$');
var match = patt2.exec(classesarr[index]);
return Number(match[0]);
}
}
}
return null;
};
/**
* Handle when the window is resized.
*/
DragDropMarkersQuestion.prototype.handleResize = function() {
var thisQ = this,
bgRatio = this.bgRatio();
if (this.isPrinting) {
bgRatio = 1;
}
this.getRoot().find('div.droparea .marker').not('.beingdragged').each(function(key, drag) {
$(drag)
.css('left', parseFloat($(drag).data('originX')) * parseFloat(bgRatio))
.css('top', parseFloat($(drag).data('originY')) * parseFloat(bgRatio));
thisQ.handleElementScale(drag, 'left top');
});
this.getRoot().find('div.droparea svg.dropzones')
.width(this.bgImage().width())
.height(this.bgImage().height());
for (var dropZoneNo = 0; dropZoneNo < this.visibleDropZones.length; dropZoneNo++) {
var dropZone = thisQ.visibleDropZones[dropZoneNo];
var originCoords = dropZone.coords;
var shape = thisQ.shapes[dropZoneNo];
var shapeSVG = thisQ.shapeSVGs[dropZoneNo];
shape.parse(originCoords, bgRatio);
shape.updateSvg(shapeSVG);
var handles = shape.getHandlePositions();
var markerSpan = this.getRoot().find('div.ddarea div.markertexts span.markertext' + dropZoneNo);
markerSpan
.css('left', handles.moveHandle.x - (markerSpan.outerWidth() / 2) - 4)
.css('top', handles.moveHandle.y - (markerSpan.outerHeight() / 2));
thisQ.handleElementScale(markerSpan, 'center');
}
};
/**
* Clone the drag.
*/
DragDropMarkersQuestion.prototype.cloneDrags = function() {
var thisQ = this;
this.getRoot().find('div.draghomes span.marker').each(function(index, draghome) {
var drag = $(draghome);
var placeHolder = drag.clone();
placeHolder.removeClass();
placeHolder.addClass('marker');
placeHolder.addClass('choice' + thisQ.getChoiceNoFromElement(drag));
placeHolder.addClass(thisQ.getDragNoClass(drag, false));
placeHolder.addClass('dragplaceholder');
drag.before(placeHolder);
});
};
/**
* Get the drag number of a drag.
*
* @param {jQuery} drag the drag.
* @returns {Number} the drag number.
*/
DragDropMarkersQuestion.prototype.getDragNo = function(drag) {
return this.getClassnameNumericSuffix(drag, 'dragno');
};
/**
* Get the drag number prefix of a drag.
*
* @param {jQuery} drag the drag.
* @param {Boolean} includeSelector include the CSS selector prefix or not.
* @return {String} Class name
*/
DragDropMarkersQuestion.prototype.getDragNoClass = function(drag, includeSelector) {
var className = 'dragno' + this.getDragNo(drag);
if (this.isInfiniteDrag(drag)) {
className = 'infinite';
}
if (includeSelector) {
return '.' + className;
}
return className;
};
/**
* Get drag clone for a given drag.
*
* @param {jQuery} drag the drag.
* @returns {jQuery} the drag's clone.
*/
DragDropMarkersQuestion.prototype.getDragClone = function(drag) {
return this.getRoot().find('.draghomes' + ' span.marker' +
'.choice' + this.getChoiceNoFromElement(drag) + this.getDragNoClass(drag, true) + '.dragplaceholder');
};
/**
* Get the drop area element.
* @returns {jQuery} droparea element.
*/
DragDropMarkersQuestion.prototype.dropArea = function() {
return this.getRoot().find('div.droparea');
};
/**
* Animate a drag back to its home.
*
* @param {jQuery} drag the item being moved.
*/
DragDropMarkersQuestion.prototype.sendDragHome = function(drag) {
drag.removeClass('beingdragged')
.addClass('unneeded')
.css('top', '')
.css('left', '')
.css('transform', '');
var placeHolder = this.getDragClone(drag);
placeHolder.after(drag);
placeHolder.removeClass('active');
};
/**
* Animate a drag item into a given place.
*
* @param {jQuery} drag the item to place.
* @param {boolean} isScaling Scaling or not.
* @param {boolean} initialLoad Whether it is the initial load or not.
*/
DragDropMarkersQuestion.prototype.sendDragToDrop = function(drag, isScaling, initialLoad = false) {
var dropArea = this.dropArea(),
bgRatio = this.bgRatio();
drag.removeClass('beingdragged').removeClass('unneeded');
var dragXY = this.convertToBgImgXY(new Shapes.Point(drag.data('pagex'), drag.data('pagey')));
if (isScaling) {
drag.data('originX', dragXY.x / bgRatio).data('originY', dragXY.y / bgRatio);
drag.css('left', dragXY.x).css('top', dragXY.y);
} else {
drag.data('originX', dragXY.x).data('originY', dragXY.y);
drag.css('left', dragXY.x * bgRatio).css('top', dragXY.y * bgRatio);
}
// We need to save the original scale ratio for each draggable item.
if (!initialLoad) {
// Only set the scale ratio for a current being-dragged item, not for the initial loading.
drag.data('scaleRatio', bgRatio);
}
dropArea.append(drag);
this.handleElementScale(drag, 'left top');
};
/**
* Clone the drag at the draghome area if needed.
*
* @param {jQuery} drag the item to place.
*/
DragDropMarkersQuestion.prototype.cloneDragIfNeeded = function(drag) {
var inputNode = this.getInput(drag),
noOfDrags = Number(this.getClassnameNumericSuffix(inputNode, 'noofdrags')),
displayedDragsInDropArea = this.getRoot().find('div.droparea .marker.choice' +
this.getChoiceNoFromElement(drag) + this.getDragNoClass(drag, true)).length,
displayedDragsInDragHomes = this.getRoot().find('div.draghomes .marker.choice' +
this.getChoiceNoFromElement(drag) + this.getDragNoClass(drag, true)).not('.dragplaceholder').length;
if ((this.isInfiniteDrag(drag) ||
!this.isInfiniteDrag(drag) && displayedDragsInDropArea < noOfDrags) && displayedDragsInDragHomes === 0) {
var dragClone = drag.clone();
dragClone.addClass('unneeded')
.css('top', '')
.css('left', '')
.css('transform', '');
this.getDragClone(drag)
.removeClass('active')
.after(dragClone);
questionManager.addEventHandlersToMarker(dragClone);
}
};
/**
* Remove the clone drag at the draghome area if needed.
*
* @param {jQuery} drag the item to place.
*/
DragDropMarkersQuestion.prototype.removeDragIfNeeded = function(drag) {
var dragsInHome = this.getRoot().find('div.draghomes .marker.choice' +
this.getChoiceNoFromElement(drag) + this.getDragNoClass(drag, true)).not('.dragplaceholder');
var displayedDrags = dragsInHome.length;
while (displayedDrags > 1) {
dragsInHome.first().remove();
displayedDrags--;
}
};
/**
* Get the input belong to drag.
*
* @param {jQuery} drag the item to place.
* @returns {jQuery} input element.
*/
DragDropMarkersQuestion.prototype.getInput = function(drag) {
var choiceNo = this.getChoiceNoFromElement(drag);
return this.getRoot().find('input.choices.choice' + choiceNo);
};
/**
* Return the background ratio.
*
* @returns {number} Background ratio.
*/
DragDropMarkersQuestion.prototype.bgRatio = function() {
var bgImg = this.bgImage();
var bgImgNaturalWidth = bgImg.get(0).naturalWidth;
var bgImgClientWidth = bgImg.width();
return bgImgClientWidth / bgImgNaturalWidth;
};
/**
* Scale the drag if needed.
*
* @param {jQuery} element the item to place.
* @param {String} type scaling type
*/
DragDropMarkersQuestion.prototype.handleElementScale = function(element, type) {
var bgRatio = parseFloat(this.bgRatio());
if (this.isPrinting) {
bgRatio = 1;
}
$(element).css({
'-webkit-transform': 'scale(' + bgRatio + ')',
'-moz-transform': 'scale(' + bgRatio + ')',
'-ms-transform': 'scale(' + bgRatio + ')',
'-o-transform': 'scale(' + bgRatio + ')',
'transform': 'scale(' + bgRatio + ')',
'transform-origin': type
});
};
/**
* Check if the given drag is in infinite mode or not.
*
* @param {jQuery} drag The drag item need to check.
*/
DragDropMarkersQuestion.prototype.isInfiniteDrag = function(drag) {
return drag.hasClass('infinite');
};
/**
* Singleton that tracks all the DragDropToTextQuestions on this page, and deals
* with event dispatching.
*
* @type {Object}
*/
var questionManager = {
/**
* {boolean} ensures that the event handlers are only initialised once per page.
*/
eventHandlersInitialised: false,
/**
* {Object} ensures that the marker event handlers are only initialised once per question,
* indexed by containerId (id on the .que div).
*/
markerEventHandlersInitialised: {},
/**
* {boolean} is printing or not.
*/
isPrinting: false,
/**
* {boolean} is keyboard navigation.
*/
isKeyboardNavigation: false,
/**
* {Object} all the questions on this page, indexed by containerId (id on the .que div).
*/
questions: {}, // An object containing all the information about each question on the page.
/**
* Initialise one question.
*
* @param {String} containerId the id of the div.que that contains this question.
* @param {boolean} readOnly whether the question is read-only.
* @param {Object[]} visibleDropZones data on any drop zones to draw as part of the feedback.
*/
init: function(containerId, readOnly, visibleDropZones) {
questionManager.questions[containerId] =
new DragDropMarkersQuestion(containerId, readOnly, visibleDropZones);
if (!questionManager.eventHandlersInitialised) {
questionManager.setupEventHandlers();
questionManager.eventHandlersInitialised = true;
}
if (!questionManager.markerEventHandlersInitialised.hasOwnProperty(containerId)) {
questionManager.markerEventHandlersInitialised[containerId] = true;
// We do not use the body event here to prevent the other event on Mobile device, such as scroll event.
var questionContainer = document.getElementById(containerId);
if (questionContainer.classList.contains('ddmarker') &&
!questionContainer.classList.contains('qtype_ddmarker-readonly')) {
// TODO: Convert all the jQuery selectors and events to native Javascript.
questionManager.addEventHandlersToMarker($(questionContainer).find('div.draghomes .marker'));
questionManager.addEventHandlersToMarker($(questionContainer).find('div.droparea .marker'));
}
}
},
/**
* Set up the event handlers that make this question type work. (Done once per page.)
*/
setupEventHandlers: function() {
$(window).on('resize', function() {
questionManager.handleWindowResize(false);
});
window.addEventListener('beforeprint', function() {
questionManager.isPrinting = true;
questionManager.handleWindowResize(questionManager.isPrinting);
});
window.addEventListener('afterprint', function() {
questionManager.isPrinting = false;
questionManager.handleWindowResize(questionManager.isPrinting);
});
setTimeout(function() {
questionManager.fixLayoutIfThingsMoved();
}, 100);
},
/**
* Binding the event again for newly created element.
*
* @param {jQuery} element Element to bind the event
*/
addEventHandlersToMarker: function(element) {
element
.on('mousedown touchstart', questionManager.handleDragStart)
.on('keydown keypress', questionManager.handleKeyPress)
.focusin(function(e) {
questionManager.handleKeyboardFocus(e, true);
})
.focusout(function(e) {
questionManager.handleKeyboardFocus(e, false);
});
},
/**
* Handle mouse down / touch start events on markers.
* @param {Event} e the DOM event.
*/
handleDragStart: function(e) {
e.preventDefault();
var question = questionManager.getQuestionForEvent(e);
if (question) {
question.handleDragStart(e);
}
},
/**
* Handle key down / press events on markers.
* @param {Event} e
*/
handleKeyPress: function(e) {
var question = questionManager.getQuestionForEvent(e);
if (question) {
question.handleKeyPress(e);
}
},
/**
* Handle when the window is resized.
* @param {boolean} isPrinting
*/
handleWindowResize: function(isPrinting) {
for (var containerId in questionManager.questions) {
if (questionManager.questions.hasOwnProperty(containerId)) {
questionManager.questions[containerId].isPrinting = isPrinting;
questionManager.questions[containerId].handleResize();
}
}
},
/**
* Handle focus lost events on markers.
* @param {Event} e
* @param {boolean} isNavigating
*/
handleKeyboardFocus: function(e, isNavigating) {
questionManager.isKeyboardNavigation = isNavigating;
},
/**
* Sometimes, despite our best efforts, things change in a way that cannot
* be specifically caught (e.g. dock expanding or collapsing in Boost).
* Therefore, we need to periodically check everything is in the right position.
*/
fixLayoutIfThingsMoved: function() {
if (!questionManager.isKeyboardNavigation) {
this.handleWindowResize(questionManager.isPrinting);
}
// We use setTimeout after finishing work, rather than setInterval,
// in case positioning things is slow. We want 100 ms gap
// between executions, not what setInterval does.
setTimeout(function() {
questionManager.fixLayoutIfThingsMoved(questionManager.isPrinting);
}, 100);
},
/**
* Given an event, work out which question it effects.
* @param {Event} e the event.
* @returns {DragDropMarkersQuestion|undefined} The question, or undefined.
*/
getQuestionForEvent: function(e) {
var containerId = $(e.currentTarget).closest('.que.ddmarker').attr('id');
return questionManager.questions[containerId];
},
/**
* Handle when the form is dirty.
*/
handleFormDirty: function() {
const responseForm = document.getElementById('responseform');
FormChangeChecker.markFormAsDirty(responseForm);
}
};
/**
* @alias module:qtype_ddmarker/question
*/
return {
/**
* Initialise one drag-drop markers question.
*
* @param {String} containerId id of the outer div for this question.
* @param {String} bgImgUrl the URL of the background image.
* @param {boolean} readOnly whether the question is being displayed read-only.
* @param {String[]} visibleDropZones the geometry of any drop-zones to show.
*/
init: questionManager.init
};
});