chart.js
Version:
Simple HTML5 charts using the canvas element.
422 lines (354 loc) • 11.1 kB
JavaScript
'use strict';
var defaults = require('../core/core.defaults');
var elements = require('../elements/index');
var helpers = require('../helpers/index');
defaults._set('bar', {
hover: {
mode: 'label'
},
scales: {
xAxes: [{
type: 'category',
// Specific to Bar Controller
categoryPercentage: 0.8,
barPercentage: 0.9,
// offset settings
offset: true,
// grid line settings
gridLines: {
offsetGridLines: true
}
}],
yAxes: [{
type: 'linear'
}]
}
});
defaults._set('horizontalBar', {
hover: {
mode: 'index',
axis: 'y'
},
scales: {
xAxes: [{
type: 'linear',
position: 'bottom'
}],
yAxes: [{
position: 'left',
type: 'category',
// Specific to Horizontal Bar Controller
categoryPercentage: 0.8,
barPercentage: 0.9,
// offset settings
offset: true,
// grid line settings
gridLines: {
offsetGridLines: true
}
}]
},
elements: {
rectangle: {
borderSkipped: 'left'
}
},
tooltips: {
callbacks: {
title: function(item, data) {
// Pick first xLabel for now
var title = '';
if (item.length > 0) {
if (item[0].yLabel) {
title = item[0].yLabel;
} else if (data.labels.length > 0 && item[0].index < data.labels.length) {
title = data.labels[item[0].index];
}
}
return title;
},
label: function(item, data) {
var datasetLabel = data.datasets[item.datasetIndex].label || '';
return datasetLabel + ': ' + item.xLabel;
}
},
mode: 'index',
axis: 'y'
}
});
module.exports = function(Chart) {
Chart.controllers.bar = Chart.DatasetController.extend({
dataElementType: elements.Rectangle,
initialize: function() {
var me = this;
var meta;
Chart.DatasetController.prototype.initialize.apply(me, arguments);
meta = me.getMeta();
meta.stack = me.getDataset().stack;
meta.bar = true;
},
update: function(reset) {
var me = this;
var rects = me.getMeta().data;
var i, ilen;
me._ruler = me.getRuler();
for (i = 0, ilen = rects.length; i < ilen; ++i) {
me.updateElement(rects[i], i, reset);
}
},
updateElement: function(rectangle, index, reset) {
var me = this;
var chart = me.chart;
var meta = me.getMeta();
var dataset = me.getDataset();
var custom = rectangle.custom || {};
var rectangleOptions = chart.options.elements.rectangle;
rectangle._xScale = me.getScaleForId(meta.xAxisID);
rectangle._yScale = me.getScaleForId(meta.yAxisID);
rectangle._datasetIndex = me.index;
rectangle._index = index;
rectangle._model = {
datasetLabel: dataset.label,
label: chart.data.labels[index],
borderSkipped: custom.borderSkipped ? custom.borderSkipped : rectangleOptions.borderSkipped,
backgroundColor: custom.backgroundColor ? custom.backgroundColor : helpers.valueAtIndexOrDefault(dataset.backgroundColor, index, rectangleOptions.backgroundColor),
borderColor: custom.borderColor ? custom.borderColor : helpers.valueAtIndexOrDefault(dataset.borderColor, index, rectangleOptions.borderColor),
borderWidth: custom.borderWidth ? custom.borderWidth : helpers.valueAtIndexOrDefault(dataset.borderWidth, index, rectangleOptions.borderWidth)
};
me.updateElementGeometry(rectangle, index, reset);
rectangle.pivot();
},
/**
* @private
*/
updateElementGeometry: function(rectangle, index, reset) {
var me = this;
var model = rectangle._model;
var vscale = me.getValueScale();
var base = vscale.getBasePixel();
var horizontal = vscale.isHorizontal();
var ruler = me._ruler || me.getRuler();
var vpixels = me.calculateBarValuePixels(me.index, index);
var ipixels = me.calculateBarIndexPixels(me.index, index, ruler);
model.horizontal = horizontal;
model.base = reset ? base : vpixels.base;
model.x = horizontal ? reset ? base : vpixels.head : ipixels.center;
model.y = horizontal ? ipixels.center : reset ? base : vpixels.head;
model.height = horizontal ? ipixels.size : undefined;
model.width = horizontal ? undefined : ipixels.size;
},
/**
* @private
*/
getValueScaleId: function() {
return this.getMeta().yAxisID;
},
/**
* @private
*/
getIndexScaleId: function() {
return this.getMeta().xAxisID;
},
/**
* @private
*/
getValueScale: function() {
return this.getScaleForId(this.getValueScaleId());
},
/**
* @private
*/
getIndexScale: function() {
return this.getScaleForId(this.getIndexScaleId());
},
/**
* Returns the effective number of stacks based on groups and bar visibility.
* @private
*/
getStackCount: function(last) {
var me = this;
var chart = me.chart;
var scale = me.getIndexScale();
var stacked = scale.options.stacked;
var ilen = last === undefined ? chart.data.datasets.length : last + 1;
var stacks = [];
var i, meta;
for (i = 0; i < ilen; ++i) {
meta = chart.getDatasetMeta(i);
if (meta.bar && chart.isDatasetVisible(i) &&
(stacked === false ||
(stacked === true && stacks.indexOf(meta.stack) === -1) ||
(stacked === undefined && (meta.stack === undefined || stacks.indexOf(meta.stack) === -1)))) {
stacks.push(meta.stack);
}
}
return stacks.length;
},
/**
* Returns the stack index for the given dataset based on groups and bar visibility.
* @private
*/
getStackIndex: function(datasetIndex) {
return this.getStackCount(datasetIndex) - 1;
},
/**
* @private
*/
getRuler: function() {
var me = this;
var scale = me.getIndexScale();
var stackCount = me.getStackCount();
var datasetIndex = me.index;
var pixels = [];
var isHorizontal = scale.isHorizontal();
var start = isHorizontal ? scale.left : scale.top;
var end = start + (isHorizontal ? scale.width : scale.height);
var i, ilen;
for (i = 0, ilen = me.getMeta().data.length; i < ilen; ++i) {
pixels.push(scale.getPixelForValue(null, i, datasetIndex));
}
return {
pixels: pixels,
start: start,
end: end,
stackCount: stackCount,
scale: scale
};
},
/**
* Note: pixel values are not clamped to the scale area.
* @private
*/
calculateBarValuePixels: function(datasetIndex, index) {
var me = this;
var chart = me.chart;
var meta = me.getMeta();
var scale = me.getValueScale();
var datasets = chart.data.datasets;
var value = scale.getRightValue(datasets[datasetIndex].data[index]);
var stacked = scale.options.stacked;
var stack = meta.stack;
var start = 0;
var i, imeta, ivalue, base, head, size;
if (stacked || (stacked === undefined && stack !== undefined)) {
for (i = 0; i < datasetIndex; ++i) {
imeta = chart.getDatasetMeta(i);
if (imeta.bar &&
imeta.stack === stack &&
imeta.controller.getValueScaleId() === scale.id &&
chart.isDatasetVisible(i)) {
ivalue = scale.getRightValue(datasets[i].data[index]);
if ((value < 0 && ivalue < 0) || (value >= 0 && ivalue > 0)) {
start += ivalue;
}
}
}
}
base = scale.getPixelForValue(start);
head = scale.getPixelForValue(start + value);
size = (head - base) / 2;
return {
size: size,
base: base,
head: head,
center: head + size / 2
};
},
/**
* @private
*/
calculateBarIndexPixels: function(datasetIndex, index, ruler) {
var me = this;
var options = ruler.scale.options;
var stackIndex = me.getStackIndex(datasetIndex);
var pixels = ruler.pixels;
var base = pixels[index];
var length = pixels.length;
var start = ruler.start;
var end = ruler.end;
var leftSampleSize, rightSampleSize, leftCategorySize, rightCategorySize, fullBarSize, size;
if (length === 1) {
leftSampleSize = base > start ? base - start : end - base;
rightSampleSize = base < end ? end - base : base - start;
} else {
if (index > 0) {
leftSampleSize = (base - pixels[index - 1]) / 2;
if (index === length - 1) {
rightSampleSize = leftSampleSize;
}
}
if (index < length - 1) {
rightSampleSize = (pixels[index + 1] - base) / 2;
if (index === 0) {
leftSampleSize = rightSampleSize;
}
}
}
leftCategorySize = leftSampleSize * options.categoryPercentage;
rightCategorySize = rightSampleSize * options.categoryPercentage;
fullBarSize = (leftCategorySize + rightCategorySize) / ruler.stackCount;
size = fullBarSize * options.barPercentage;
size = Math.min(
helpers.valueOrDefault(options.barThickness, size),
helpers.valueOrDefault(options.maxBarThickness, Infinity));
base -= leftCategorySize;
base += fullBarSize * stackIndex;
base += (fullBarSize - size) / 2;
return {
size: size,
base: base,
head: base + size,
center: base + size / 2
};
},
draw: function() {
var me = this;
var chart = me.chart;
var scale = me.getValueScale();
var rects = me.getMeta().data;
var dataset = me.getDataset();
var ilen = rects.length;
var i = 0;
helpers.canvas.clipArea(chart.ctx, chart.chartArea);
for (; i < ilen; ++i) {
if (!isNaN(scale.getRightValue(dataset.data[i]))) {
rects[i].draw();
}
}
helpers.canvas.unclipArea(chart.ctx);
},
setHoverStyle: function(rectangle) {
var dataset = this.chart.data.datasets[rectangle._datasetIndex];
var index = rectangle._index;
var custom = rectangle.custom || {};
var model = rectangle._model;
model.backgroundColor = custom.hoverBackgroundColor ? custom.hoverBackgroundColor : helpers.valueAtIndexOrDefault(dataset.hoverBackgroundColor, index, helpers.getHoverColor(model.backgroundColor));
model.borderColor = custom.hoverBorderColor ? custom.hoverBorderColor : helpers.valueAtIndexOrDefault(dataset.hoverBorderColor, index, helpers.getHoverColor(model.borderColor));
model.borderWidth = custom.hoverBorderWidth ? custom.hoverBorderWidth : helpers.valueAtIndexOrDefault(dataset.hoverBorderWidth, index, model.borderWidth);
},
removeHoverStyle: function(rectangle) {
var dataset = this.chart.data.datasets[rectangle._datasetIndex];
var index = rectangle._index;
var custom = rectangle.custom || {};
var model = rectangle._model;
var rectangleElementOptions = this.chart.options.elements.rectangle;
model.backgroundColor = custom.backgroundColor ? custom.backgroundColor : helpers.valueAtIndexOrDefault(dataset.backgroundColor, index, rectangleElementOptions.backgroundColor);
model.borderColor = custom.borderColor ? custom.borderColor : helpers.valueAtIndexOrDefault(dataset.borderColor, index, rectangleElementOptions.borderColor);
model.borderWidth = custom.borderWidth ? custom.borderWidth : helpers.valueAtIndexOrDefault(dataset.borderWidth, index, rectangleElementOptions.borderWidth);
}
});
Chart.controllers.horizontalBar = Chart.controllers.bar.extend({
/**
* @private
*/
getValueScaleId: function() {
return this.getMeta().xAxisID;
},
/**
* @private
*/
getIndexScaleId: function() {
return this.getMeta().yAxisID;
}
});
};