react-native-pathjs-charts
Version:
Cross platform React Native charting library based on path-js and react-native-svg
196 lines (161 loc) • 6.64 kB
JavaScript
/*
Copyright 2016 Capital One Services, LLC
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and limitations under the License.
SPDX-Copyright: Copyright (c) Capital One Services, LLC
SPDX-License-Identifier: Apache-2.0
*/
import React, {Component} from 'react'
import { Circle, G, Path, Text } from 'react-native-svg'
import { fontAdapt } from './util'
import _ from 'lodash'
const Pathjs = require('paths-js/path')
export class AxisStruct {
constructor(scale, options, chartArea, horizontal) {
this.scale = scale
this.options = options
this.chartArea = chartArea
this.margin = chartArea.margin
this.horizontal = horizontal
}
static calcStepSize(range, targetSteps)
{
const tempStep = range / targetSteps
const mag = Math.floor(Math.log(tempStep) / Math.log(10))
const magPow = Math.pow(10, mag)
let magMsd = Math.round(tempStep / magPow + 0.5)
if (magMsd > 5.0)
magMsd = 10.0
else if (magMsd > 2.0)
magMsd = 5.0
else if (magMsd > 1.0)
magMsd = 2.0
return magMsd * magPow
}
static roundFloat(floatVal, decimalPlaces) {
return Math.round(parseFloat((floatVal * Math.pow(10, decimalPlaces)).toFixed(decimalPlaces))) / Math.pow(10, decimalPlaces)
}
static getTickValues(axis, tickCount, decimalPlaces) {
const tickStep = AxisStruct.calcStepSize((axis.maxValue - axis.minValue),tickCount)
const maxTick = axis.minValue + (tickCount * tickStep)
let tickValues = _.range(axis.minValue, maxTick, tickStep)
tickValues = tickValues.map(tickValue => {
return AxisStruct.roundFloat(tickValue, decimalPlaces)
})
return tickValues
}
axis() {
const horizontal = this.horizontal
const xAxis = this.chartArea.x
const yAxis = this.chartArea.y
const currentAxis = horizontal?xAxis:yAxis
const tickInterval = this.options.tickCount || 10
const decimalPlaces = this.options.decimalPlaces || 2
const ticks = this.options.tickValues !== undefined && this.options.tickValues.length !== 0? _.map(this.options.tickValues,function(v){return v.value }):AxisStruct.getTickValues(currentAxis, tickInterval, decimalPlaces)
const fixed = this.options.zeroAxis?this.scale(0):horizontal?yAxis.min:xAxis.min
const start = {x: horizontal?xAxis.min:fixed, y: horizontal?fixed:yAxis.min}
const end = {x:horizontal?xAxis.max:fixed,y: horizontal?fixed:yAxis.max}
const tailLength = this.options.tailLength || 10
const margin = this.margin
if (margin !== undefined){
if (horizontal){
start.x += (margin.left - tailLength) || 0
start.y += margin.top || 0
end.x += (margin.left) || 0
end.y += margin.top || 0
}
else {
start.x += margin.left || 0
start.y += (margin.top + tailLength) || 0
end.x += margin.left || 0
end.y += (margin.top - tailLength) || 0
}
}
return {
item: currentAxis,
path: Pathjs().moveto(start).lineto(end).closepath(),
ticks: ticks,
lines: ticks.map((c,i) => {
let scaleBase = isNaN(c) ? i : c
const lineStart = {x: horizontal ? this.scale(scaleBase) + margin.left : xAxis.min + margin.left, y: horizontal ? yAxis.min + margin.top : this.scale(scaleBase) + margin.top}
return Pathjs().moveto(lineStart).lineto(horizontal ? lineStart.x : xAxis.max + margin.left, horizontal ? yAxis.max + (margin.top - tailLength) : lineStart.y)
},this)
}
}
}
export default class Axis extends Component {
render() {
const { chartArea, options, scale } = this.props
const horizontal = options.orient ==='top' || options.orient ==='bottom'
const axis = new AxisStruct(scale,options,chartArea,horizontal).axis()
let textAnchor = 'start'
if (options.orient === 'top' || options.orient === 'bottom') textAnchor = 'middle'
if (options.orient === 'left') textAnchor = 'end'
if (options.orient === 'right') textAnchor = 'start'
let xy = [0,0]
if (options.orient === 'top') xy = [0,-5]
if (options.orient === 'bottom') xy = [0,5]
if (options.orient === 'left') xy = [-5,-10]
if (options.orient === 'right') xy = [5,5]
if (typeof options.color !== 'string') {
options.color = '#3E90F0'
}
if (typeof options.opacity !== 'number') {
options.opacity = 0.5
}
if (typeof options.strokeWidth !== 'number') {
options.strokeWidth = 3
}
if (typeof options.tickSize !== 'number') {
options.tickSize = 2
}
if (typeof options.tickColor !== 'string') {
options.tickColor = 'grey'
}
const textStyle = fontAdapt(options.label)
const ticks =_.map(axis.ticks, function (c, i) {
const label = options.labelFunction !== undefined? options.labelFunction.apply(this, [c]) : c
let scaleBase = isNaN(c) ? i : c
let gxy = horizontal ? [scale(scaleBase),chartArea.y.min]:[chartArea.x.min,scale(scaleBase)]
let returnValue
if (label !== undefined && label !== null) {
returnValue =
<G key={i} x={gxy[0]} y={gxy[1]}>
{options.showTicks &&
<Circle r={options.tickSize} cx="0" cy="0" stroke={options.tickColor} fill={options.tickColor} />
}
{options.showLabels &&
<Text x={xy[0]} y={xy[1]}
fontFamily={textStyle.fontFamily}
fontSize={textStyle.fontSize}
fontWeight={textStyle.fontWeight}
fontStyle={textStyle.fontStyle}
fill={textStyle.fill}
textAnchor={textAnchor}>
{label}
</Text>}
</G>
}
return returnValue
})
let offset = {
x: chartArea.margin.left * -1,
y: chartArea.margin.top * -1
// x: 0,
// y: 0
}
let returnV = <G>
<G x={offset.x} y={offset.y}>
{options.showAxis ? <Path d={axis.path.print()} strokeOpacity={options.opacity} stroke={options.color} strokeWidth={options.strokeWidth} fill="none"/> : null}
</G>
{ticks}
</G>
return returnV
}
}