/**
* @license Highcharts JS v5.0.2 (2016-10-26)
* Accessibility module
*
* (c) 2010-2016 Highsoft AS
* Author: Oystein Moseng
*
* License: www.highcharts.com/license
*/
(function(factory) {
if (typeof module === 'object' && module.exports) {
module.exports = factory;
} else {
factory(Highcharts);
}
}(function(Highcharts) {
(function(H) {
/**
* Accessibility module
*
* (c) 2010-2016 Highsoft AS
* Author: Oystein Moseng
*
* License: www.highcharts.com/license
*/
'use strict';
var win = H.win,
doc = win.document,
each = H.each,
erase = H.erase,
addEvent = H.addEvent,
removeEvent = H.removeEvent,
fireEvent = H.fireEvent,
dateFormat = H.dateFormat,
merge = H.merge,
// Human readable description of series and each point in singular and plural
typeToSeriesMap = {
'default': ['series', 'data point', 'data points'],
'line': ['line', 'data point', 'data points'],
'spline': ['line', 'data point', 'data points'],
'area': ['line', 'data point', 'data points'],
'areaspline': ['line', 'data point', 'data points'],
'pie': ['pie', 'slice', 'slices'],
'column': ['column series', 'column', 'columns'],
'bar': ['bar series', 'bar', 'bars'],
'scatter': ['scatter series', 'data point', 'data points'],
'boxplot': ['boxplot series', 'box', 'boxes'],
'arearange': ['arearange series', 'data point', 'data points'],
'areasplinerange': ['areasplinerange series', 'data point', 'data points'],
'bubble': ['bubble series', 'bubble', 'bubbles'],
'columnrange': ['columnrange series', 'column', 'columns'],
'errorbar': ['errorbar series', 'errorbar', 'errorbars'],
'funnel': ['funnel', 'data point', 'data points'],
'pyramid': ['pyramid', 'data point', 'data points'],
'waterfall': ['waterfall series', 'column', 'columns'],
'map': ['map', 'area', 'areas'],
'mapline': ['line', 'data point', 'data points'],
'mappoint': ['point series', 'data point', 'data points'],
'mapbubble': ['bubble series', 'bubble', 'bubbles']
},
// Descriptions for exotic chart types
typeDescriptionMap = {
boxplot: ' Box plot charts are typically used to display groups of statistical data. ' +
'Each data point in the chart can have up to 5 values: minimum, lower quartile, median, upper quartile and maximum. ',
arearange: ' Arearange charts are line charts displaying a range between a lower and higher value for each point. ',
areasplinerange: ' These charts are line charts displaying a range between a lower and higher value for each point. ',
bubble: ' Bubble charts are scatter charts where each data point also has a size value. ',
columnrange: ' Columnrange charts are column charts displaying a range between a lower and higher value for each point. ',
errorbar: ' Errorbar series are used to display the variability of the data. ',
funnel: ' Funnel charts are used to display reduction of data in stages. ',
pyramid: ' Pyramid charts consist of a single pyramid with item heights corresponding to each point value. ',
waterfall: ' A waterfall chart is a column chart where each column contributes towards a total end value. '
},
commonKeys = ['name', 'id', 'category', 'x', 'value', 'y'],
specialKeys = ['z', 'open', 'high', 'q3', 'median', 'q1', 'low', 'close']; // Tell user about all properties if points have one of these defined
// Default a11y options
H.setOptions({
accessibility: {
enabled: true,
pointDescriptionThreshold: 30, // set to false to disable
keyboardNavigation: {
enabled: true
// skipNullPoints: false
}
// describeSingleSeries: false
}
});
// Utility function. Reverses child nodes of a DOM element
function reverseChildNodes(node) {
var i = node.childNodes.length;
while (i--) {
node.appendChild(node.childNodes[i]);
}
}
// Utility function to attempt to fake a click event on an element
function fakeClickEvent(element) {
var fakeEvent;
if (element && element.onclick) {
fakeEvent = doc.createEvent('Events');
fakeEvent.initEvent('click', true, false);
element.onclick(fakeEvent);
}
}
// Whenever drawing series, put info on DOM elements
H.wrap(H.Series.prototype, 'render', function(proceed) {
proceed.apply(this, Array.prototype.slice.call(arguments, 1));
if (this.chart.options.accessibility.enabled) {
this.setA11yDescription();
}
});
// Put accessible info on series and points of a series
H.Series.prototype.setA11yDescription = function() {
var a11yOptions = this.chart.options.accessibility,
firstPointEl = this.points && this.points.length && this.points[0].graphic && this.points[0].graphic.element,
seriesEl = firstPointEl && firstPointEl.parentNode || this.graph && this.graph.element || this.group && this.group.element; // Could be tracker series depending on series type
if (seriesEl) {
// For some series types the order of elements do not match the order of points in series
// In that case we have to reverse them in order for AT to read them out in an understandable order
if (seriesEl.lastChild === firstPointEl) {
reverseChildNodes(seriesEl);
}
// Make individual point elements accessible if possible. Note: If markers are disabled there might not be any elements there to make accessible.
if (this.points && (this.points.length < a11yOptions.pointDescriptionThreshold || a11yOptions.pointDescriptionThreshold === false)) {
each(this.points, function(point) {
if (point.graphic) {
point.graphic.element.setAttribute('role', 'img');
point.graphic.element.setAttribute('tabindex', '-1');
point.graphic.element.setAttribute('aria-label', a11yOptions.pointDescriptionFormatter && a11yOptions.pointDescriptionFormatter(point) ||
point.buildPointInfoString());
}
});
}
// Make series element accessible
if (this.chart.series.length > 1 || a11yOptions.describeSingleSeries) {
seriesEl.setAttribute('role', 'region');
seriesEl.setAttribute('tabindex', '-1');
seriesEl.setAttribute('aria-label', a11yOptions.seriesDescriptionFormatter && a11yOptions.seriesDescriptionFormatter(this) ||
this.buildSeriesInfoString());
}
}
};
// Return string with information about series
H.Series.prototype.buildSeriesInfoString = function() {
var typeInfo = typeToSeriesMap[this.type] || typeToSeriesMap.default,
description = this.description || this.options.description;
return (this.name ? this.name + ', ' : '') +
(this.chart.types.length === 1 ? typeInfo[0] : 'series') + ' ' + (this.index + 1) + ' of ' + (this.chart.series.length) +
(this.chart.types.length === 1 ? ' with ' : '. ' + typeInfo[0] + ' with ') +
(this.points.length + ' ' + (this.points.length === 1 ? typeInfo[1] : typeInfo[2])) +
(description ? '. ' + description : '') +
(this.chart.yAxis.length > 1 && this.yAxis ? '. Y axis, ' + this.yAxis.getDescription() : '') +
(this.chart.xAxis.length > 1 && this.xAxis ? '. X axis, ' + this.xAxis.getDescription() : '');
};
// Return string with information about point
H.Point.prototype.buildPointInfoString = function() {
var point = this,
series = point.series,
a11yOptions = series.chart.options.accessibility,
infoString = '',
hasSpecialKey = false,
dateTimePoint = series.xAxis && series.xAxis.isDatetimeAxis,
timeDesc = dateTimePoint && dateFormat(a11yOptions.pointDateFormatter && a11yOptions.pointDateFormatter(point) || a11yOptions.pointDateFormat ||
H.Tooltip.prototype.getXDateFormat(point, series.chart.options.tooltip, series.xAxis), point.x);
each(specialKeys, function(key) {
if (point[key] !== undefined) {
hasSpecialKey = true;
}
});
// If the point has one of the less common properties defined, display all that are defined
if (hasSpecialKey) {
if (dateTimePoint) {
infoString = timeDesc;
}
each(commonKeys.concat(specialKeys), function(key) {
if (point[key] !== undefined && !(dateTimePoint && key === 'x')) {
infoString += (infoString ? '. ' : '') + key + ', ' + this[key];
}
});
} else {
// Pick and choose properties for a succint label
infoString = (this.name || timeDesc || this.category || this.id || 'x, ' + this.x) + ', ' +
(this.value !== undefined ? this.value : this.y);
}
return (this.index + 1) + '. ' + infoString + '.' + (this.description ? ' ' + this.description : '');
};
// Get descriptive label for axis
H.Axis.prototype.getDescription = function() {
return this.userOptions && this.userOptions.description || this.axisTitle && this.axisTitle.textStr ||
this.options.id || this.categories && 'categories' || 'values';
};
// Pan along axis in a direction (1 or -1), optionally with a defined granularity (number of steps it takes to walk across current view)
H.Axis.prototype.panStep = function(direction, granularity) {
var gran = granularity || 3,
extremes = this.getExtremes(),
step = (extremes.max - extremes.min) / gran * direction,
newMax = extremes.max + step,
newMin = extremes.min + step,
size = newMax - newMin;
if (direction < 0 && newMin < extremes.dataMin) {
newMin = extremes.dataMin;
newMax = newMin + size;
} else if (direction > 0 && newMax > extremes.dataMax) {
newMax = extremes.dataMax;
newMin = newMax - size;
}
this.setExtremes(newMin, newMax);
};
// Whenever adding or removing series, keep track of types present in chart
H.wrap(H.Series.prototype, 'init', function(proceed) {
proceed.apply(this, Array.prototype.slice.call(arguments, 1));
var chart = this.chart;
if (chart.options.accessibility.enabled) {
chart.types = chart.types || [];
// Add type to list if does not exist
if (chart.types.indexOf(this.type) < 0) {
chart.types.push(this.type);
}
addEvent(this, 'remove', function() {
var removedSeries = this,
hasType = false;
// Check if any of the other series have the same type as this one. Otherwise remove it from the list.
each(chart.series, function(s) {
if (s !== removedSeries && chart.types.indexOf(removedSeries.type) < 0) {
hasType = true;
}
});
if (!hasType) {
erase(chart.types, removedSeries.type);
}
});
}
});
// Return simplified description of chart type. Some types will not be familiar to most screen reader users, but we try.
H.Chart.prototype.getTypeDescription = function() {
var firstType = this.types && this.types[0],
mapTitle = this.series[0] && this.series[0].mapTitle;
if (!firstType) {
return 'Empty chart.';
} else if (firstType === 'map') {
return mapTitle ? 'Map of ' + mapTitle : 'Map of unspecified region.';
} else if (this.types.length > 1) {
return 'Combination chart.';
} else if (['spline', 'area', 'areaspline'].indexOf(firstType) > -1) {
return 'Line chart.';
}
return firstType + ' chart.' + (typeDescriptionMap[firstType] || '');
};
// Return object with text description of each of the chart's axes
H.Chart.prototype.getAxesDescription = function() {
var numXAxes = this.xAxis.length,
numYAxes = this.yAxis.length,
desc = {},
i;
if (numXAxes) {
desc.xAxis = 'The chart has ' + numXAxes + (numXAxes > 1 ? ' X axes' : ' X axis') + ' displaying ';
if (numXAxes < 2) {
desc.xAxis += this.xAxis[0].getDescription() + '.';
} else {
for (i = 0; i < numXAxes - 1; ++i) {
desc.xAxis += (i ? ', ' : '') + this.xAxis[i].getDescription();
}
desc.xAxis += ' and ' + this.xAxis[i].getDescription() + '.';
}
}
if (numYAxes) {
desc.yAxis = 'The chart has ' + numYAxes + (numYAxes > 1 ? ' Y axes' : ' Y axis') + ' displaying ';
if (numYAxes < 2) {
desc.yAxis += this.yAxis[0].getDescription() + '.';
} else {
for (i = 0; i < numYAxes - 1; ++i) {
desc.yAxis += (i ? ', ' : '') + this.yAxis[i].getDescription();
}
desc.yAxis += ' and ' + this.yAxis[i].getDescription() + '.';
}
}
return desc;
};
// Set a11y attribs on exporting menu
H.Chart.prototype.addAccessibleContextMenuAttribs = function() {
var exportList = this.exportDivElements;
if (exportList) {
// Set tabindex on the menu items to allow focusing by script
// Set role to give screen readers a chance to pick up the contents
each(exportList, function(item) {
if (item.tagName === 'DIV' &&
!(item.children && item.children.length)) {
item.setAttribute('role', 'menuitem');
item.setAttribute('tabindex', -1);
}
});
// Set accessibility properties on parent div
exportList[0].parentNode.setAttribute('role', 'menu');
exportList[0].parentNode.setAttribute('aria-label', 'Chart export');
}
};
// Highlight a point (show tooltip and display hover state). Returns the highlighted point.
H.Point.prototype.highlight = function() {
var chart = this.series.chart;
if (this.graphic && this.graphic.element.focus) {
this.graphic.element.focus();
}
if (!this.isNull) {
this.onMouseOver(); // Show the hover marker
chart.tooltip.refresh(chart.tooltip.shared ? [this] : this); // Show the tooltip
} else {
chart.tooltip.hide(0);
// Don't call blur on the element, as it messes up the chart div's focus
}
chart.highlightedPoint = this;
return this;
};
// Function to highlight next/previous point in chart
// Returns highlighted point on success, false on failure (no adjacent point to highlight in chosen direction)
H.Chart.prototype.highlightAdjacentPoint = function(next) {
var series = this.series,
curPoint = this.highlightedPoint,
curPointIndex = curPoint && curPoint.index || 0,
newSeries,
newPoint;
// If no points, return false
if (!series[0] || !series[0].points) {
return false;
}
// Use first point if none already highlighted
if (!curPoint) {
return series[0].points[0].highlight();
}
// Find index of current point in series.points array. Necessary for dataGrouping (and maybe zoom?)
if (curPoint.series.points[curPointIndex] !== curPoint) {
for (var i = 0; i < curPoint.series.points.length; ++i) {
if (curPoint.series.points[i] === curPoint) {
curPointIndex = i;
break;
}
}
}
// Try to grab next/prev point
newSeries = series[curPoint.series.index + (next ? 1 : -1)];
newPoint = curPoint.series.points[curPointIndex + (next ? 1 : -1)] || newSeries && newSeries.points[next ? 0 : newSeries.points.length - 1];
// If there is no adjacent point, we return false
if (newPoint === undefined) {
return false;
}
// Recursively skip null points
if (newPoint.isNull && this.options.accessibility.keyboardNavigation &&
this.options.accessibility.keyboardNavigation.skipNullPoints) {
this.highlightedPoint = newPoint;
return this.highlightAdjacentPoint(next);
}
// There is an adjacent point, highlight it
return newPoint.highlight();
};
// Show the export menu and focus the first item (if exists)
H.Chart.prototype.showExportMenu = function() {
if (this.exportSVGElements && this.exportSVGElements[0]) {
this.exportSVGElements[0].element.onclick();
this.highlightExportItem(0);
}
};
// Highlight export menu item by index
H.Chart.prototype.highlightExportItem = function(ix) {
var listItem = this.exportDivElements && this.exportDivElements[ix],
curHighlighted = this.exportDivElements && this.exportDivElements[this.highlightedExportItem];
if (listItem && listItem.tagName === 'DIV' && !(listItem.children && listItem.children.length)) {
if (listItem.focus) {
listItem.focus();
}
if (curHighlighted && curHighlighted.onmouseout) {
curHighlighted.onmouseout();
}
if (listItem.onmouseover) {
listItem.onmouseover();
}
this.highlightedExportItem = ix;
return true;
}
};
// Highlight range selector button by index
H.Chart.prototype.highlightRangeSelectorButton = function(ix) {
var buttons = this.rangeSelector.buttons;
// Deselect old
if (buttons[this.highlightedRangeSelectorItemIx]) {
buttons[this.highlightedRangeSelectorItemIx].setState(this.oldRangeSelectorItemState || 0);
}
// Select new
this.highlightedRangeSelectorItemIx = ix;
if (buttons[ix]) {
if (buttons[ix].element.focus) {
buttons[ix].element.focus();
}
this.oldRangeSelectorItemState = buttons[ix].state;
buttons[ix].setState(2);
return true;
}
return false;
};
// Highlight legend item by index
H.Chart.prototype.highlightLegendItem = function(ix) {
var items = this.legend.allItems;
if (items[this.highlightedLegendItemIx]) {
fireEvent(items[this.highlightedLegendItemIx].legendGroup.element, 'mouseout');
}
this.highlightedLegendItemIx = ix;
if (items[ix]) {
if (items[ix].legendGroup.element.focus) {
items[ix].legendGroup.element.focus();
}
fireEvent(items[ix].legendGroup.element, 'mouseover');
return true;
}
return false;
};
// Hide export menu
H.Chart.prototype.hideExportMenu = function() {
var exportList = this.exportDivElements;
if (exportList) {
each(exportList, function(el) {
fireEvent(el, 'mouseleave');
});
if (exportList[this.highlightedExportItem] && exportList[this.highlightedExportItem].onmouseout) {
exportList[this.highlightedExportItem].onmouseout();
}
this.highlightedExportItem = 0;
this.renderTo.focus();
}
};
// Add keyboard navigation handling to chart
H.Chart.prototype.addKeyboardNavEvents = function() {
var chart = this;
// Abstraction layer for keyboard navigation. Keep a map of keyCodes to handler functions, and a next/prev move handler for tab order.
// The module's keyCode handlers determine when to move to another module.
// Validate holds a function to determine if there are prerequisites for this module to run that are not met.
// Init holds a function to run once before any keyCodes are interpreted.
// transformTabs determines whether to transform tabs to left/right events or not. Defaults to true.
function KeyboardNavigationModule(options) {
this.keyCodeMap = options.keyCodeMap;
this.move = options.move;
this.validate = options.validate;
this.init = options.init;
this.transformTabs = options.transformTabs !== false;
}
KeyboardNavigationModule.prototype = {
// Find handler function(s) for key code in the keyCodeMap and run it.
run: function(e) {
var navModule = this,
keyCode = e.which || e.keyCode,
handled = false;
keyCode = this.transformTabs && keyCode === 9 ? (e.shiftKey ? 37 : 39) : keyCode; // Transform tabs
each(this.keyCodeMap, function(codeSet) {
if (codeSet[0].indexOf(keyCode) > -1) {
handled = codeSet[1].call(navModule, keyCode, e) === false ? false : true; // If explicitly returning false, we haven't handled it
}
});
return handled;
}
};
// Maintain abstraction between KeyboardNavigationModule and Highcharts
// The chart object keeps track of a list of KeyboardNavigationModules that we move through
function navModuleFactory(keyMap, options) {
return new KeyboardNavigationModule(merge({
keyCodeMap: keyMap,
// Move to next/prev valid module, or undefined if none, and init it.
// Returns true on success and false if there is no valid module to move to.
move: function(direction) {
chart.keyboardNavigationModuleIndex += direction;
var newModule = chart.keyboardNavigationModules[chart.keyboardNavigationModuleIndex];
if (newModule) {
if (newModule.validate && !newModule.validate()) {
return this.move(direction); // Invalid module
}
if (newModule.init) {
newModule.init(direction); // Valid module, init it
return true;
}
}
// No module
chart.keyboardNavigationModuleIndex = 0; // Reset counter
chart.slipNextTab = true; // Allow next tab to slip, as we will have focus on chart now
return false;
}
}, options));
}
// Route keydown events
function keydownHandler(ev) {
var e = ev || win.event,
keyCode = e.which || e.keyCode,
curNavModule = chart.keyboardNavigationModules[chart.keyboardNavigationModuleIndex];
// Handle tabbing
if (keyCode === 9) {
// If we reached end of chart, we need to let this tab slip through to allow users to tab further
if (chart.slipNextTab) {
chart.slipNextTab = false;
return;
}
}
// If key was not tab, don't slip the next tab
chart.slipNextTab = false;
// If there is a navigation module for the current index, run it. Otherwise, we are outside of the chart in some direction.
if (curNavModule) {
if (curNavModule.run(e)) {
e.preventDefault(); // If successfully handled, stop the event here.
}
}
}
// List of the different keyboard handling modes we use depending on where we are in the chart.
// Each mode has a set of handling functions mapped to key codes.
// Each mode determines when to move to the next/prev mode.
chart.keyboardNavigationModules = [
// Points
navModuleFactory([
// Left/Right
[
[37, 39],
function(keyCode) {
if (!chart.highlightAdjacentPoint(keyCode === 39)) { // Try to highlight adjacent point
return this.move(keyCode === 39 ? 1 : -1); // Failed. Move to next/prev module
}
}
],
// Up/Down
[
[38, 40],
function(keyCode) {
var newSeries;
if (chart.highlightedPoint) {
newSeries = chart.series[chart.highlightedPoint.series.index + (keyCode === 38 ? -1 : 1)]; // Find prev/next series
if (newSeries && newSeries.points[0]) { // If series exists and has data, go for it
newSeries.points[0].highlight();
} else {
return this.move(keyCode === 40 ? 1 : -1); // Otherwise, attempt to move to next/prev module
}
}
}
],
// Enter/Spacebar
[
[13, 32],
function() {
if (chart.highlightedPoint) {
chart.highlightedPoint.firePointEvent('click');
}
}
]
], {
// If coming back to points from other module, highlight last point
init: function(direction) {
var lastSeries = chart.series && chart.series[chart.series.length - 1],
lastPoint = lastSeries && lastSeries.points && lastSeries.points[lastSeries.points.length - 1];
if (direction < 0 && lastPoint) {
lastPoint.highlight();
}
}
}),
// Exporting
navModuleFactory([
// Left/Up
[
[37, 38],
function() {
var i = chart.highlightedExportItem || 0,
reachedEnd = true,
series = chart.series,
newSeries;
// Try to highlight prev item in list. Highlighting e.g. separators will fail.
while (i--) {
if (chart.highlightExportItem(i)) {
reachedEnd = false;
break;
}
}
if (reachedEnd) {
chart.hideExportMenu();
// Wrap to last point
if (series && series.length) {
newSeries = series[series.length - 1];
if (newSeries.points.length) {
newSeries.points[newSeries.points.length - 1].highlight();
}
}
// Try to move to prev module (should be points, since we wrapped to last point)
return this.move(-1);
}
}
],
// Right/Down
[
[39, 40],
function() {
var highlightedExportItem = chart.highlightedExportItem || 0,
reachedEnd = true;
// Try to highlight next item in list. Highlighting e.g. separators will fail.
for (var i = highlightedExportItem + 1; i < chart.exportDivElements.length; ++i) {
if (chart.highlightExportItem(i)) {
reachedEnd = false;
break;
}
}
if (reachedEnd) {
chart.hideExportMenu();
return this.move(1); // Next module
}
}
],
// Enter/Spacebar
[
[13, 32],
function() {
fakeClickEvent(chart.exportDivElements[chart.highlightedExportItem]);
}
]
], {
// Only run exporting navigation if exporting support exists and is enabled on chart
validate: function() {
return chart.exportChart && !(chart.options.exporting && chart.options.exporting.enabled === false);
},
// Show export menu
init: function(direction) {
chart.highlightedPoint = null;
chart.showExportMenu();
// If coming back to export menu from other module, try to highlight last item in menu
if (direction < 0 && chart.exportDivElements) {
for (var i = chart.exportDivElements.length; i > -1; --i) {
if (chart.highlightExportItem(i)) {
break;
}
}
}
}
}),
// Map zoom
navModuleFactory([
// Up/down/left/right
[
[38, 40, 37, 39],
function(keyCode) {
chart[keyCode === 38 || keyCode === 40 ? 'yAxis' : 'xAxis'][0].panStep(keyCode < 39 ? -1 : 1);
}
],
// Tabs
[
[9],
function(keyCode, e) {
var button;
chart.mapNavButtons[chart.focusedMapNavButtonIx].setState(0); // Deselect old
if (e.shiftKey && !chart.focusedMapNavButtonIx || !e.shiftKey && chart.focusedMapNavButtonIx) { // trying to go somewhere we can't?
chart.mapZoom(); // Reset zoom
return this.move(e.shiftKey ? -1 : 1); // Nowhere to go, go to prev/next module
}
chart.focusedMapNavButtonIx += e.shiftKey ? -1 : 1;
button = chart.mapNavButtons[chart.focusedMapNavButtonIx];
if (button.element.focus) {
button.element.focus();
}
button.setState(2);
}
],
// Enter/Spacebar
[
[13, 32],
function() {
fakeClickEvent(chart.mapNavButtons[chart.focusedMapNavButtonIx].element);
}
]
], {
// Only run this module if we have map zoom on the chart
validate: function() {
return chart.mapZoom && chart.mapNavButtons && chart.mapNavButtons.length === 2;
},
// Handle tabs separately
transformTabs: false,
// Make zoom buttons do their magic
init: function(direction) {
var zoomIn = chart.mapNavButtons[0],
zoomOut = chart.mapNavButtons[1],
initialButton = direction > 0 ? zoomIn : zoomOut;
each(chart.mapNavButtons, function(button, i) {
button.element.setAttribute('tabindex', -1);
button.element.setAttribute('role', 'button');
button.element.setAttribute('aria-label', 'Zoom ' + (i ? 'out' : '') + 'chart');
});
if (initialButton.element.focus) {
initialButton.element.focus();
}
initialButton.setState(2);
chart.focusedMapNavButtonIx = direction > 0 ? 0 : 1;
}
}),
// Highstock range selector (minus input boxes)
navModuleFactory([
// Left/Right/Up/Down
[
[37, 39, 38, 40],
function(keyCode) {
var direction = (keyCode === 37 || keyCode === 38) ? -1 : 1;
// Try to highlight next/prev button
if (!chart.highlightRangeSelectorButton(chart.highlightedRangeSelectorItemIx + direction)) {
return this.move(direction);
}
}
],
// Enter/Spacebar
[
[13, 32],
function() {
if (chart.oldRangeSelectorItemState !== 3) { // Don't allow click if button used to be disabled
fakeClickEvent(chart.rangeSelector.buttons[chart.highlightedRangeSelectorItemIx].element);
}
}
]
], {
// Only run this module if we have range selector
validate: function() {
return chart.rangeSelector && chart.rangeSelector.buttons && chart.rangeSelector.buttons.length;
},
// Make elements focusable and accessible
init: function(direction) {
each(chart.rangeSelector.buttons, function(button) {
button.element.setAttribute('tabindex', '-1');
button.element.setAttribute('role', 'button');
button.element.setAttribute('aria-label', 'Select range ' + (button.text && button.text.textStr));
});
// Focus first/last button
chart.highlightRangeSelectorButton(direction > 0 ? 0 : chart.rangeSelector.buttons.length - 1);
}
}),
// Highstock range selector, input boxes
navModuleFactory([
// Tab/Up/Down
[
[9, 38, 40],
function(keyCode, e) {
var direction = (keyCode === 9 && e.shiftKey || keyCode === 38) ? -1 : 1,
newIx = chart.highlightedInputRangeIx = chart.highlightedInputRangeIx + direction;
// Try to highlight next/prev item in list.
if (newIx > 1 || newIx < 0) { // Out of range
return this.move(direction);
}
chart.rangeSelector[newIx ? 'maxInput' : 'minInput'].focus(); // Input boxes are HTML, and should have focus support in all browsers
}
]
], {
// Only run if we have range selector with input boxes
validate: function() {
var inputVisible = chart.rangeSelector && chart.rangeSelector.inputGroup && chart.rangeSelector.inputGroup.element.getAttribute('visibility') !== 'hidden';
return inputVisible && chart.options.rangeSelector.inputEnabled !== false && chart.rangeSelector.minInput && chart.rangeSelector.maxInput;
},
// Handle tabs different from left/right (because we don't want to catch left/right in a text area)
transformTabs: false,
// Highlight first/last input box
init: function(direction) {
chart.highlightedInputRangeIx = direction > 0 ? 0 : 1;
chart.rangeSelector[chart.highlightedInputRangeIx ? 'maxInput' : 'minInput'].focus();
}
}),
// Legend navigation
navModuleFactory([
// Left/Right/Up/Down
[
[37, 39, 38, 40],
function(keyCode) {
var direction = (keyCode === 37 || keyCode === 38) ? -1 : 1;
// Try to highlight next/prev legend item
if (!chart.highlightLegendItem(chart.highlightedLegendItemIx + direction)) {
return this.move(direction);
}
}
],
// Enter/Spacebar
[
[13, 32],
function() {
fakeClickEvent(chart.legend.allItems[chart.highlightedLegendItemIx].legendItem.element.parentNode);
}
]
], {
// Only run this module if we have at least one legend - wait for it - item.
validate: function() {
return chart.legend && chart.legend.allItems && !chart.colorAxis;
},
// Make elements focusable and accessible
init: function(direction) {
each(chart.legend.allItems, function(item) {
item.legendGroup.element.setAttribute('tabindex', '-1');
item.legendGroup.element.setAttribute('role', 'button');
item.legendGroup.element.setAttribute('aria-label', 'Toggle visibility of series ' + item.name);
});
// Focus first/last item
chart.highlightLegendItem(direction > 0 ? 0 : chart.legend.allItems.length - 1);
}
})
];
// Init nav module index. We start at the first module, and as the user navigates through the chart the index will increase to use different handler modules.
chart.keyboardNavigationModuleIndex = 0;
// Make chart reachable by tab
if (!chart.renderTo.tabIndex) {
chart.renderTo.setAttribute('tabindex', '0');
}
// Handle keyboard events
addEvent(chart.renderTo, 'keydown', keydownHandler);
addEvent(chart, 'destroy', function() {
removeEvent(chart.renderTo, 'keydown', keydownHandler);
});
};
// Add screen reader region to chart.
// tableId is the HTML id of the table to focus when clicking the table anchor in the screen reader region.
H.Chart.prototype.addScreenReaderRegion = function(tableId) {
var chart = this,
series = chart.series,
options = chart.options,
a11yOptions = options.accessibility,
hiddenSection = chart.screenReaderRegion = doc.createElement('div'),
tableShortcut = doc.createElement('h3'),
tableShortcutAnchor = doc.createElement('a'),
chartHeading = doc.createElement('h3'),
hiddenStyle = { // CSS style to hide element from visual users while still exposing it to screen readers
position: 'absolute',
left: '-9999px',
top: 'auto',
width: '1px',
height: '1px',
overflow: 'hidden'
},
chartTypes = chart.types || [],
// Build axis info - but not for pies and maps. Consider not adding for certain other types as well (funnel, pyramid?)
axesDesc = (chartTypes.length === 1 && chartTypes[0] === 'pie' || chartTypes[0] === 'map') && {} || chart.getAxesDescription(),
chartTypeInfo = series[0] && typeToSeriesMap[series[0].type] || typeToSeriesMap.default;
hiddenSection.setAttribute('role', 'region');
hiddenSection.setAttribute('aria-label', 'Chart screen reader information.');
hiddenSection.innerHTML = a11yOptions.screenReaderSectionFormatter && a11yOptions.screenReaderSectionFormatter(chart) ||
'Use regions/landmarks to skip ahead to chart' +
(series.length > 1 ? ' and navigate between data series' : '') + '.
Summary.
' + (options.title.text || 'Chart') +
(options.subtitle && options.subtitle.text ? '. ' + options.subtitle.text : '') +
'
Long description.
' + (options.chart.description || 'No description available.') +
'
Structure.
Chart type: ' + (options.chart.typeDescription || chart.getTypeDescription()) + '
' +
(series.length === 1 ? '' + chartTypeInfo[0] + ' with ' + series[0].points.length + ' ' +
(series[0].points.length === 1 ? chartTypeInfo[1] : chartTypeInfo[2]) + '.
' : '') +
(axesDesc.xAxis ? ('' + axesDesc.xAxis + '
') : '') +
(axesDesc.yAxis ? ('' + axesDesc.yAxis + '
') : '');
// Add shortcut to data table if export-csv is loaded
if (chart.getCSV) {
tableShortcutAnchor.innerHTML = 'View as data table.';
tableShortcutAnchor.href = '#' + tableId;
tableShortcutAnchor.setAttribute('tabindex', '-1'); // Make this unreachable by user tabbing
tableShortcutAnchor.onclick = a11yOptions.onTableAnchorClick || function() {
chart.viewData();
doc.getElementById(tableId).focus();
};
tableShortcut.appendChild(tableShortcutAnchor);
hiddenSection.appendChild(tableShortcut);
}
chartHeading.innerHTML = 'Chart graphic.';
chart.renderTo.insertBefore(chartHeading, chart.renderTo.firstChild);
chart.renderTo.insertBefore(hiddenSection, chart.renderTo.firstChild);
// Hide the section and the chart heading
merge(true, chartHeading.style, hiddenStyle);
merge(true, hiddenSection.style, hiddenStyle);
};
// Make chart container accessible, and wrap table functionality
H.Chart.prototype.callbacks.push(function(chart) {
var options = chart.options,
a11yOptions = options.accessibility;
if (!a11yOptions.enabled) {
return;
}
var titleElement = doc.createElementNS('http://www.w3.org/2000/svg', 'title'),
exportGroupElement = doc.createElementNS('http://www.w3.org/2000/svg', 'g'),
descElement = chart.container.getElementsByTagName('desc')[0],
textElements = chart.container.getElementsByTagName('text'),
titleId = 'highcharts-title-' + chart.index,
tableId = 'highcharts-data-table-' + chart.index,
chartTitle = options.title.text || 'Chart',
oldColumnHeaderFormatter = options.exporting && options.exporting.csv && options.exporting.csv.columnHeaderFormatter,
topLevelColumns = [];
// Add SVG title/desc tags
titleElement.textContent = chartTitle;
titleElement.id = titleId;
descElement.parentNode.insertBefore(titleElement, descElement);
chart.renderTo.setAttribute('role', 'region');
chart.renderTo.setAttribute('aria-label', chartTitle + '. Use up and down arrows to navigate.');
// Set screen reader properties on export menu
if (chart.exportSVGElements && chart.exportSVGElements[0] && chart.exportSVGElements[0].element) {
var oldExportCallback = chart.exportSVGElements[0].element.onclick,
parent = chart.exportSVGElements[0].element.parentNode;
chart.exportSVGElements[0].element.onclick = function() {
oldExportCallback.apply(this, Array.prototype.slice.call(arguments));
chart.addAccessibleContextMenuAttribs();
chart.highlightExportItem(0);
};
chart.exportSVGElements[0].element.setAttribute('role', 'button');
chart.exportSVGElements[0].element.setAttribute('aria-label', 'View export menu');
exportGroupElement.appendChild(chart.exportSVGElements[0].element);
exportGroupElement.setAttribute('role', 'region');
exportGroupElement.setAttribute('aria-label', 'Chart export menu');
parent.appendChild(exportGroupElement);
}
// Set screen reader properties on input boxes for range selector. We need to do this regardless of whether or not these are visible, as they are
// by default part of the page's tabindex unless we set them to -1.
if (chart.rangeSelector) {
each(['minInput', 'maxInput'], function(key, i) {
if (chart.rangeSelector[key]) {
chart.rangeSelector[key].setAttribute('tabindex', '-1');
chart.rangeSelector[key].setAttribute('role', 'textbox');
chart.rangeSelector[key].setAttribute('aria-label', 'Select ' + (i ? 'end' : 'start') + ' date.');
}
});
}
// Hide text elements from screen readers
each(textElements, function(el) {
el.setAttribute('aria-hidden', 'true');
});
// Add top-secret screen reader region
chart.addScreenReaderRegion(tableId);
// Enable keyboard navigation
if (a11yOptions.keyboardNavigation) {
chart.addKeyboardNavEvents();
}
/* Wrap table functionality from export-csv */
// Keep track of columns
merge(true, options.exporting, {
csv: {
columnHeaderFormatter: function(series, key, keyLength) {
var prevCol = topLevelColumns[topLevelColumns.length - 1];
if (keyLength > 1) {
// We need multiple levels of column headers
// Populate a list of column headers to add in addition to the ones added by export-csv
if ((prevCol && prevCol.text) !== series.name) {
topLevelColumns.push({
text: series.name,
span: keyLength
});
}
}
if (oldColumnHeaderFormatter) {
return oldColumnHeaderFormatter.call(this, series, key, keyLength);
}
return keyLength > 1 ? key : series.name;
}
}
});
// Add ID and title/caption to table HTML
H.wrap(chart, 'getTable', function(proceed) {
return proceed.apply(this, Array.prototype.slice.call(arguments, 1))
.replace('', '' + chartTitle + '');
});
// Add accessibility attributes and top level columns
H.wrap(chart, 'viewData', function(proceed) {
if (!this.insertedTable) {
proceed.apply(this, Array.prototype.slice.call(arguments, 1));
var table = doc.getElementById(tableId),
body = table.getElementsByTagName('tbody')[0],
firstRow = body.firstChild.children,
columnHeaderRow = ' | ',
cell,
newCell;
// Make table focusable by script
table.setAttribute('tabindex', '-1');
// Create row headers
each(body.children, function(el) {
cell = el.firstChild;
newCell = doc.createElement('th');
newCell.setAttribute('scope', 'row');
newCell.innerHTML = cell.innerHTML;
cell.parentNode.replaceChild(newCell, cell);
});
// Set scope for column headers
each(firstRow, function(el) {
if (el.tagName === 'TH') {
el.setAttribute('scope', 'col');
}
});
// Add top level columns
if (topLevelColumns.length) {
each(topLevelColumns, function(col) {
columnHeaderRow += '' + col.text + ' | ';
});
body.insertAdjacentHTML('afterbegin', columnHeaderRow);
}
}
});
});
}(Highcharts));
}));
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