Chart.js/src/core/core.tooltip.js

717 lines
20 KiB
JavaScript
Executable File

"use strict";
module.exports = function(Chart) {
var helpers = Chart.helpers;
Chart.defaults.global.tooltips = {
enabled: true,
custom: null,
mode: 'single',
backgroundColor: "rgba(0,0,0,0.8)",
titleFontStyle: "bold",
titleSpacing: 2,
titleMarginBottom: 6,
titleFontColor: "#fff",
titleAlign: "left",
bodySpacing: 2,
bodyFontColor: "#fff",
bodyAlign: "left",
footerFontStyle: "bold",
footerSpacing: 2,
footerMarginTop: 6,
footerFontColor: "#fff",
footerAlign: "left",
yPadding: 6,
xPadding: 6,
yAlign : 'center',
xAlign : 'center',
caretSize: 5,
cornerRadius: 6,
multiKeyBackground: '#fff',
callbacks: {
// Args are: (tooltipItems, data)
beforeTitle: helpers.noop,
title: function(tooltipItems, data) {
// Pick first xLabel for now
var title = '';
var labels = data.labels;
var labelCount = labels ? labels.length : 0;
if (tooltipItems.length > 0) {
var item = tooltipItems[0];
if (item.xLabel) {
title = item.xLabel;
} else if (labelCount > 0 && item.index < labelCount) {
title = labels[item.index];
}
}
return title;
},
afterTitle: helpers.noop,
// Args are: (tooltipItems, data)
beforeBody: helpers.noop,
// Args are: (tooltipItem, data)
beforeLabel: helpers.noop,
label: function(tooltipItem, data) {
var datasetLabel = data.datasets[tooltipItem.datasetIndex].label || '';
return datasetLabel + ': ' + tooltipItem.yLabel;
},
labelColor: function(tooltipItem, chartInstance) {
var meta = chartInstance.getDatasetMeta(tooltipItem.datasetIndex);
var activeElement = meta.data[tooltipItem.index];
var view = activeElement._view;
return {
borderColor: view.borderColor,
backgroundColor: view.backgroundColor
};
},
afterLabel: helpers.noop,
// Args are: (tooltipItems, data)
afterBody: helpers.noop,
// Args are: (tooltipItems, data)
beforeFooter: helpers.noop,
footer: helpers.noop,
afterFooter: helpers.noop
}
};
// Helper to push or concat based on if the 2nd parameter is an array or not
function pushOrConcat(base, toPush) {
if (toPush) {
if (helpers.isArray(toPush)) {
//base = base.concat(toPush);
Array.prototype.push.apply(base, toPush);
} else {
base.push(toPush);
}
}
return base;
}
function getAveragePosition(elements) {
if (!elements.length) {
return false;
}
var i, len;
var xPositions = [];
var yPositions = [];
for (i = 0, len = elements.length; i < len; ++i) {
var el = elements[i];
if (el && el.hasValue()){
var pos = el.tooltipPosition();
xPositions.push(pos.x);
yPositions.push(pos.y);
}
}
var x = 0,
y = 0;
for (i = 0; i < xPositions.length; ++i) {
if (xPositions[ i ]) {
x += xPositions[i];
y += yPositions[i];
}
}
return {
x: Math.round(x / xPositions.length),
y: Math.round(y / xPositions.length)
};
}
// Private helper to create a tooltip iteam model
// @param element : the chart element (point, arc, bar) to create the tooltip item for
// @return : new tooltip item
function createTooltipItem(element) {
var xScale = element._xScale;
var yScale = element._yScale || element._scale; // handle radar || polarArea charts
var index = element._index,
datasetIndex = element._datasetIndex;
return {
xLabel: xScale ? xScale.getLabelForIndex(index, datasetIndex) : '',
yLabel: yScale ? yScale.getLabelForIndex(index, datasetIndex) : '',
index: index,
datasetIndex: datasetIndex
};
}
Chart.Tooltip = Chart.Element.extend({
initialize: function() {
var me = this;
var globalDefaults = Chart.defaults.global;
var tooltipOpts = me._options;
var getValueOrDefault = helpers.getValueOrDefault;
helpers.extend(me, {
_model: {
// Positioning
xPadding: tooltipOpts.xPadding,
yPadding: tooltipOpts.yPadding,
xAlign : tooltipOpts.xAlign,
yAlign : tooltipOpts.yAlign,
// Body
bodyFontColor: tooltipOpts.bodyFontColor,
_bodyFontFamily: getValueOrDefault(tooltipOpts.bodyFontFamily, globalDefaults.defaultFontFamily),
_bodyFontStyle: getValueOrDefault(tooltipOpts.bodyFontStyle, globalDefaults.defaultFontStyle),
_bodyAlign: tooltipOpts.bodyAlign,
bodyFontSize: getValueOrDefault(tooltipOpts.bodyFontSize, globalDefaults.defaultFontSize),
bodySpacing: tooltipOpts.bodySpacing,
// Title
titleFontColor: tooltipOpts.titleFontColor,
_titleFontFamily: getValueOrDefault(tooltipOpts.titleFontFamily, globalDefaults.defaultFontFamily),
_titleFontStyle: getValueOrDefault(tooltipOpts.titleFontStyle, globalDefaults.defaultFontStyle),
titleFontSize: getValueOrDefault(tooltipOpts.titleFontSize, globalDefaults.defaultFontSize),
_titleAlign: tooltipOpts.titleAlign,
titleSpacing: tooltipOpts.titleSpacing,
titleMarginBottom: tooltipOpts.titleMarginBottom,
// Footer
footerFontColor: tooltipOpts.footerFontColor,
_footerFontFamily: getValueOrDefault(tooltipOpts.footerFontFamily, globalDefaults.defaultFontFamily),
_footerFontStyle: getValueOrDefault(tooltipOpts.footerFontStyle, globalDefaults.defaultFontStyle),
footerFontSize: getValueOrDefault(tooltipOpts.footerFontSize, globalDefaults.defaultFontSize),
_footerAlign: tooltipOpts.footerAlign,
footerSpacing: tooltipOpts.footerSpacing,
footerMarginTop: tooltipOpts.footerMarginTop,
// Appearance
caretSize: tooltipOpts.caretSize,
cornerRadius: tooltipOpts.cornerRadius,
backgroundColor: tooltipOpts.backgroundColor,
opacity: 0,
legendColorBackground: tooltipOpts.multiKeyBackground
}
});
},
// Get the title
// Args are: (tooltipItem, data)
getTitle: function() {
var me = this;
var opts = me._options;
var callbacks = opts.callbacks;
var beforeTitle = callbacks.beforeTitle.apply(me, arguments),
title = callbacks.title.apply(me, arguments),
afterTitle = callbacks.afterTitle.apply(me, arguments);
var lines = [];
lines = pushOrConcat(lines, beforeTitle);
lines = pushOrConcat(lines, title);
lines = pushOrConcat(lines, afterTitle);
return lines;
},
// Args are: (tooltipItem, data)
getBeforeBody: function() {
var lines = this._options.callbacks.beforeBody.apply(this, arguments);
return helpers.isArray(lines) ? lines : lines !== undefined ? [lines] : [];
},
// Args are: (tooltipItem, data)
getBody: function(tooltipItems, data) {
var me = this;
var callbacks = me._options.callbacks;
var bodyItems = [];
helpers.each(tooltipItems, function(tooltipItem) {
var bodyItem = {
before: [],
lines: [],
after: []
};
pushOrConcat(bodyItem.before, callbacks.beforeLabel.call(me, tooltipItem, data));
pushOrConcat(bodyItem.lines, callbacks.label.call(me, tooltipItem, data));
pushOrConcat(bodyItem.after, callbacks.afterLabel.call(me, tooltipItem, data));
bodyItems.push(bodyItem);
});
return bodyItems;
},
// Args are: (tooltipItem, data)
getAfterBody: function() {
var lines = this._options.callbacks.afterBody.apply(this, arguments);
return helpers.isArray(lines) ? lines : lines !== undefined ? [lines] : [];
},
// Get the footer and beforeFooter and afterFooter lines
// Args are: (tooltipItem, data)
getFooter: function() {
var me = this;
var callbacks = me._options.callbacks;
var beforeFooter = callbacks.beforeFooter.apply(me, arguments);
var footer = callbacks.footer.apply(me, arguments);
var afterFooter = callbacks.afterFooter.apply(me, arguments);
var lines = [];
lines = pushOrConcat(lines, beforeFooter);
lines = pushOrConcat(lines, footer);
lines = pushOrConcat(lines, afterFooter);
return lines;
},
update: function(changed) {
var me = this;
var opts = me._options;
var model = me._model;
var active = me._active;
var data = me._data;
var chartInstance = me._chartInstance;
var i, len;
if (active.length) {
model.opacity = 1;
var labelColors = [],
tooltipPosition = getAveragePosition(active);
var tooltipItems = [];
for (i = 0, len = active.length; i < len; ++i) {
tooltipItems.push(createTooltipItem(active[i]));
}
// If the user provided a sorting function, use it to modify the tooltip items
if (opts.itemSort) {
tooltipItems = tooltipItems.sort(function(a,b) {
return opts.itemSort(a,b, data);
});
}
// If there is more than one item, show color items
if (active.length > 1) {
helpers.each(tooltipItems, function(tooltipItem) {
labelColors.push(opts.callbacks.labelColor.call(me, tooltipItem, chartInstance));
});
}
// Build the Text Lines
helpers.extend(model, {
title: me.getTitle(tooltipItems, data),
beforeBody: me.getBeforeBody(tooltipItems, data),
body: me.getBody(tooltipItems, data),
afterBody: me.getAfterBody(tooltipItems, data),
footer: me.getFooter(tooltipItems, data),
x: Math.round(tooltipPosition.x),
y: Math.round(tooltipPosition.y),
caretPadding: helpers.getValueOrDefault(tooltipPosition.padding, 2),
labelColors: labelColors
});
// We need to determine alignment of
var tooltipSize = me.getTooltipSize(model);
me.determineAlignment(tooltipSize); // Smart Tooltip placement to stay on the canvas
helpers.extend(model, me.getBackgroundPoint(model, tooltipSize));
} else {
me._model.opacity = 0;
}
if (changed && opts.custom) {
opts.custom.call(me, model);
}
return me;
},
getTooltipSize: function(vm) {
var ctx = this._chart.ctx;
var size = {
height: vm.yPadding * 2, // Tooltip Padding
width: 0
};
// Count of all lines in the body
var body = vm.body;
var combinedBodyLength = body.reduce(function(count, bodyItem) {
return count + bodyItem.before.length + bodyItem.lines.length + bodyItem.after.length;
}, 0);
combinedBodyLength += vm.beforeBody.length + vm.afterBody.length;
var titleLineCount = vm.title.length;
var footerLineCount = vm.footer.length;
var titleFontSize = vm.titleFontSize,
bodyFontSize = vm.bodyFontSize,
footerFontSize = vm.footerFontSize;
size.height += titleLineCount * titleFontSize; // Title Lines
size.height += (titleLineCount - 1) * vm.titleSpacing; // Title Line Spacing
size.height += titleLineCount ? vm.titleMarginBottom : 0; // Title's bottom Margin
size.height += combinedBodyLength * bodyFontSize; // Body Lines
size.height += combinedBodyLength ? (combinedBodyLength - 1) * vm.bodySpacing : 0; // Body Line Spacing
size.height += footerLineCount ? vm.footerMarginTop : 0; // Footer Margin
size.height += footerLineCount * (footerFontSize); // Footer Lines
size.height += footerLineCount ? (footerLineCount - 1) * vm.footerSpacing : 0; // Footer Line Spacing
// Title width
var widthPadding = 0;
var maxLineWidth = function(line) {
size.width = Math.max(size.width, ctx.measureText(line).width + widthPadding);
};
ctx.font = helpers.fontString(titleFontSize, vm._titleFontStyle, vm._titleFontFamily);
helpers.each(vm.title, maxLineWidth);
// Body width
ctx.font = helpers.fontString(bodyFontSize, vm._bodyFontStyle, vm._bodyFontFamily);
helpers.each(vm.beforeBody.concat(vm.afterBody), maxLineWidth);
// Body lines may include some extra width due to the color box
widthPadding = body.length > 1 ? (bodyFontSize + 2) : 0;
helpers.each(body, function(bodyItem) {
helpers.each(bodyItem.before, maxLineWidth);
helpers.each(bodyItem.lines, maxLineWidth);
helpers.each(bodyItem.after, maxLineWidth);
});
// Reset back to 0
widthPadding = 0;
// Footer width
ctx.font = helpers.fontString(footerFontSize, vm._footerFontStyle, vm._footerFontFamily);
helpers.each(vm.footer, maxLineWidth);
// Add padding
size.width += 2 * vm.xPadding;
return size;
},
determineAlignment: function(size) {
var me = this;
var model = me._model;
var chart = me._chart;
var chartArea = me._chartInstance.chartArea;
if (model.y < size.height) {
model.yAlign = 'top';
} else if (model.y > (chart.height - size.height)) {
model.yAlign = 'bottom';
}
var lf, rf; // functions to determine left, right alignment
var olf, orf; // functions to determine if left/right alignment causes tooltip to go outside chart
var yf; // function to get the y alignment if the tooltip goes outside of the left or right edges
var midX = (chartArea.left + chartArea.right) / 2;
var midY = (chartArea.top + chartArea.bottom) / 2;
if (model.yAlign === 'center') {
lf = function(x) {
return x <= midX;
};
rf = function(x) {
return x > midX;
};
} else {
lf = function(x) {
return x <= (size.width / 2);
};
rf = function(x) {
return x >= (chart.width - (size.width / 2));
};
}
olf = function(x) {
return x + size.width > chart.width;
};
orf = function(x) {
return x - size.width < 0;
};
yf = function(y) {
return y <= midY ? 'top' : 'bottom';
};
if (lf(model.x)) {
model.xAlign = 'left';
// Is tooltip too wide and goes over the right side of the chart.?
if (olf(model.x)) {
model.xAlign = 'center';
model.yAlign = yf(model.y);
}
} else if (rf(model.x)) {
model.xAlign = 'right';
// Is tooltip too wide and goes outside left edge of canvas?
if (orf(model.x)) {
model.xAlign = 'center';
model.yAlign = yf(model.y);
}
}
},
getBackgroundPoint: function(vm, size) {
// Background Position
var pt = {
x: vm.x,
y: vm.y
};
var caretSize = vm.caretSize,
caretPadding = vm.caretPadding,
cornerRadius = vm.cornerRadius,
xAlign = vm.xAlign,
yAlign = vm.yAlign,
paddingAndSize = caretSize + caretPadding,
radiusAndPadding = cornerRadius + caretPadding;
if (xAlign === 'right') {
pt.x -= size.width;
} else if (xAlign === 'center') {
pt.x -= (size.width / 2);
}
if (yAlign === 'top') {
pt.y += paddingAndSize;
} else if (yAlign === 'bottom') {
pt.y -= size.height + paddingAndSize;
} else {
pt.y -= (size.height / 2);
}
if (yAlign === 'center') {
if (xAlign === 'left') {
pt.x += paddingAndSize;
} else if (xAlign === 'right') {
pt.x -= paddingAndSize;
}
} else {
if (xAlign === 'left') {
pt.x -= radiusAndPadding;
} else if (xAlign === 'right') {
pt.x += radiusAndPadding;
}
}
return pt;
},
drawCaret: function(tooltipPoint, size, opacity) {
var vm = this._view;
var ctx = this._chart.ctx;
var x1, x2, x3;
var y1, y2, y3;
var caretSize = vm.caretSize;
var cornerRadius = vm.cornerRadius;
var xAlign = vm.xAlign,
yAlign = vm.yAlign;
var ptX = tooltipPoint.x,
ptY = tooltipPoint.y;
var width = size.width,
height = size.height;
if (yAlign === 'center') {
// Left or right side
if (xAlign === 'left') {
x1 = ptX;
x2 = x1 - caretSize;
x3 = x1;
} else {
x1 = ptX + width;
x2 = x1 + caretSize;
x3 = x1;
}
y2 = ptY + (height / 2);
y1 = y2 - caretSize;
y3 = y2 + caretSize;
} else {
if (xAlign === 'left') {
x1 = ptX + cornerRadius;
x2 = x1 + caretSize;
x3 = x2 + caretSize;
} else if (xAlign === 'right') {
x1 = ptX + width - cornerRadius;
x2 = x1 - caretSize;
x3 = x2 - caretSize;
} else {
x2 = ptX + (width / 2);
x1 = x2 - caretSize;
x3 = x2 + caretSize;
}
if (yAlign === 'top') {
y1 = ptY;
y2 = y1 - caretSize;
y3 = y1;
} else {
y1 = ptY + height;
y2 = y1 + caretSize;
y3 = y1;
}
}
var bgColor = helpers.color(vm.backgroundColor);
ctx.fillStyle = bgColor.alpha(opacity * bgColor.alpha()).rgbString();
ctx.beginPath();
ctx.moveTo(x1, y1);
ctx.lineTo(x2, y2);
ctx.lineTo(x3, y3);
ctx.closePath();
ctx.fill();
},
drawTitle: function(pt, vm, ctx, opacity) {
var title = vm.title;
if (title.length) {
ctx.textAlign = vm._titleAlign;
ctx.textBaseline = "top";
var titleFontSize = vm.titleFontSize,
titleSpacing = vm.titleSpacing;
var titleFontColor = helpers.color(vm.titleFontColor);
ctx.fillStyle = titleFontColor.alpha(opacity * titleFontColor.alpha()).rgbString();
ctx.font = helpers.fontString(titleFontSize, vm._titleFontStyle, vm._titleFontFamily);
var i, len;
for (i = 0, len = title.length; i < len; ++i) {
ctx.fillText(title[i], pt.x, pt.y);
pt.y += titleFontSize + titleSpacing; // Line Height and spacing
if (i + 1 === title.length) {
pt.y += vm.titleMarginBottom - titleSpacing; // If Last, add margin, remove spacing
}
}
}
},
drawBody: function(pt, vm, ctx, opacity) {
var bodyFontSize = vm.bodyFontSize;
var bodySpacing = vm.bodySpacing;
var body = vm.body;
ctx.textAlign = vm._bodyAlign;
ctx.textBaseline = "top";
var bodyFontColor = helpers.color(vm.bodyFontColor);
var textColor = bodyFontColor.alpha(opacity * bodyFontColor.alpha()).rgbString();
ctx.fillStyle = textColor;
ctx.font = helpers.fontString(bodyFontSize, vm._bodyFontStyle, vm._bodyFontFamily);
// Before Body
var xLinePadding = 0;
var fillLineOfText = function(line) {
ctx.fillText(line, pt.x + xLinePadding, pt.y);
pt.y += bodyFontSize + bodySpacing;
};
// Before body lines
helpers.each(vm.beforeBody, fillLineOfText);
var drawColorBoxes = body.length > 1;
xLinePadding = drawColorBoxes ? (bodyFontSize + 2) : 0;
// Draw body lines now
helpers.each(body, function(bodyItem, i) {
helpers.each(bodyItem.before, fillLineOfText);
helpers.each(bodyItem.lines, function(line) {
// Draw Legend-like boxes if needed
if (drawColorBoxes) {
// Fill a white rect so that colours merge nicely if the opacity is < 1
ctx.fillStyle = helpers.color(vm.legendColorBackground).alpha(opacity).rgbaString();
ctx.fillRect(pt.x, pt.y, bodyFontSize, bodyFontSize);
// Border
ctx.strokeStyle = helpers.color(vm.labelColors[i].borderColor).alpha(opacity).rgbaString();
ctx.strokeRect(pt.x, pt.y, bodyFontSize, bodyFontSize);
// Inner square
ctx.fillStyle = helpers.color(vm.labelColors[i].backgroundColor).alpha(opacity).rgbaString();
ctx.fillRect(pt.x + 1, pt.y + 1, bodyFontSize - 2, bodyFontSize - 2);
ctx.fillStyle = textColor;
}
fillLineOfText(line);
});
helpers.each(bodyItem.after, fillLineOfText);
});
// Reset back to 0 for after body
xLinePadding = 0;
// After body lines
helpers.each(vm.afterBody, fillLineOfText);
pt.y -= bodySpacing; // Remove last body spacing
},
drawFooter: function(pt, vm, ctx, opacity) {
var footer = vm.footer;
if (footer.length) {
pt.y += vm.footerMarginTop;
ctx.textAlign = vm._footerAlign;
ctx.textBaseline = "top";
var footerFontColor = helpers.color(vm.footerFontColor);
ctx.fillStyle = footerFontColor.alpha(opacity * footerFontColor.alpha()).rgbString();
ctx.font = helpers.fontString(vm.footerFontSize, vm._footerFontStyle, vm._footerFontFamily);
helpers.each(footer, function(line) {
ctx.fillText(line, pt.x, pt.y);
pt.y += vm.footerFontSize + vm.footerSpacing;
});
}
},
draw: function() {
var ctx = this._chart.ctx;
var vm = this._view;
if (vm.opacity === 0) {
return;
}
var tooltipSize = this.getTooltipSize(vm);
var pt = {
x: vm.x,
y: vm.y
};
// IE11/Edge does not like very small opacities, so snap to 0
var opacity = Math.abs(vm.opacity < 1e-3) ? 0 : vm.opacity;
if (this._options.enabled) {
// Draw Background
var bgColor = helpers.color(vm.backgroundColor);
ctx.fillStyle = bgColor.alpha(opacity * bgColor.alpha()).rgbString();
helpers.drawRoundedRectangle(ctx, pt.x, pt.y, tooltipSize.width, tooltipSize.height, vm.cornerRadius);
ctx.fill();
// Draw Caret
this.drawCaret(pt, tooltipSize, opacity);
// Draw Title, Body, and Footer
pt.x += vm.xPadding;
pt.y += vm.yPadding;
// Titles
this.drawTitle(pt, vm, ctx, opacity);
// Body
this.drawBody(pt, vm, ctx, opacity);
// Footer
this.drawFooter(pt, vm, ctx, opacity);
}
}
});
};