ChartUtils 是用于在 Power BI 视觉对象中创建轴、数据标签和图例的一组接口和方法。
安装
要安装包,应在包含当前视觉对象的目录中运行以下命令:
npm install powerbi-visuals-utils-chartutils --save
轴帮助程序
轴帮助程序(utils 中的 axis 对象)提供用于简化具有轴的操作的函数。
该模块提供了以下函数:
getRecommendedNumberOfTicksForXAxis
此函数根据图表的宽度返回建议的时钟周期数。
function getRecommendedNumberOfTicksForXAxis(availableWidth: number): number;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
axis.getRecommendedNumberOfTicksForXAxis(1024);
// returns: 8
getRecommendedNumberOfTicksForYAxis
此函数根据图表的高度返回建议的时钟周期数。
function getRecommendedNumberOfTicksForYAxis(availableWidth: number);
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
axis.getRecommendedNumberOfTicksForYAxis(100);
// returns: 3
getBestNumberOfTicks
根据最小值、最大值、度量值元数据和最大滴答计数获取最佳时钟周期数。
function getBestNumberOfTicks(
min: number,
max: number,
valuesMetadata: DataViewMetadataColumn[],
maxTickCount: number,
isDateTime?: boolean
): number;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
var dataViewMetadataColumnWithIntegersOnly: powerbi.DataViewMetadataColumn[] = [
{
displayName: "col1",
isMeasure: true,
type: ValueType.fromDescriptor({ integer: true })
},
{
displayName: "col2",
isMeasure: true,
type: ValueType.fromDescriptor({ integer: true })
}
];
var actual = axis.getBestNumberOfTicks(
0,
3,
dataViewMetadataColumnWithIntegersOnly,
6
);
// returns: 4
getTickLabelMargins
此函数返回时钟周期标签的边距。
function getTickLabelMargins(
viewport: IViewport,
yMarginLimit: number,
textWidthMeasurer: ITextAsSVGMeasurer,
textHeightMeasurer: ITextAsSVGMeasurer,
axes: CartesianAxisProperties,
bottomMarginLimit: number,
properties: TextProperties,
scrollbarVisible?: boolean,
showOnRight?: boolean,
renderXAxis?: boolean,
renderY1Axis?: boolean,
renderY2Axis?: boolean
): TickLabelMargins;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
axis.getTickLabelMargins(
plotArea,
marginLimits.left,
TextMeasurementService.measureSvgTextWidth,
TextMeasurementService.estimateSvgTextHeight,
axes,
marginLimits.bottom,
textProperties,
/*scrolling*/ false,
showY1OnRight,
renderXAxis,
renderY1Axis,
renderY2Axis
);
// returns: xMax, yLeft, yRight, stackHeigh;
isOrdinal
检查字符串是否为 null、未定义或为空。
function isOrdinal(type: ValueTypeDescriptor): boolean;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
let type = ValueType.fromDescriptor({ misc: { barcode: true } });
axis.isOrdinal(type);
// returns: true
isDateTime
检查值是否为日期/时间类型。
function isDateTime(type: ValueTypeDescriptor): boolean;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
axis.isDateTime(ValueType.fromDescriptor({ dateTime: true }));
// returns: true
getCategoryThickness
使用 D3 刻度获取实际的类别粗细。
function getCategoryThickness(scale: any): number;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
let range = [0, 100];
let domain = [0, 10];
let scale = d3.scale
.linear()
.domain(domain)
.range(range);
let actualThickness = axis.getCategoryThickness(scale);
invertOrdinalScale
此函数用于反转序号刻度。 如果 x < scale.range()[0],则返回 scale.domain()[0]。 否则,返回 <= x 的 scale.domain() 中的最大项。
function invertOrdinalScale(scale: d3.scale.Ordinal<any, any>, x: number);
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
let domain: number[] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
pixelSpan: number = 100,
ordinalScale: d3.scale.ordinal = axis.createOrdinalScale(
pixelSpan,
domain,
0.4
);
axis.invertOrdinalScale(ordinalScale, 49);
// returns: 4
findClosestXAxisIndex
此函数查找并返回最近的 x 轴索引。
function findClosestXAxisIndex(
categoryValue: number,
categoryAxisValues: AxisHelperCategoryDataPoint[]
): number;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
/**
* Finds the index of the category of the given x coordinate given.
* pointX is in non-scaled screen-space, and offsetX is in render-space.
* offsetX does not need any scaling adjustment.
* @param {number} pointX The mouse coordinate in screen-space, without scaling applied
* @param {number} offsetX Any left offset in d3.scale render-space
* @return {number}
*/
private findIndex(pointX: number, offsetX?: number): number {
// we are using mouse coordinates that do not know about any potential CSS transform scale
let xScale = this.scaleDetector.getScale().x;
if (!Double.equalWithPrecision(xScale, 1.0, 0.00001)) {
pointX = pointX / xScale;
}
if (offsetX) {
pointX += offsetX;
}
let index = axis.invertScale(this.xAxisProperties.scale, pointX);
if (this.data.isScalar) {
// When we have scalar data the inverted scale produces a category value, so we need to search for the closest index.
index = axis.findClosestXAxisIndex(index, this.data.categoryData);
}
return index;
}
diffScaled
此函数计算并返回刻度差值。
function diffScaled(
scale: d3.scale.Linear<any, any>,
value1: any,
value2: any
): number;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
var scale: d3.scale.Linear<number, number>,
range = [0, 999],
domain = [0, 1, 2, 3, 4, 5, 6, 7, 8, 999];
scale = d3.scale.linear()
.range(range)
.domain(domain);
return axis.diffScaled(scale, 0, 0));
// returns: 0
createDomain
此函数创建轴的值域。
function createDomain(
data: any[],
axisType: ValueTypeDescriptor,
isScalar: boolean,
forcedScalarDomain: any[],
ensureDomain?: NumberRange
): number[];
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
var cartesianSeries = [
{
data: [
{ categoryValue: 7, value: 11, categoryIndex: 0, seriesIndex: 0 },
{
categoryValue: 9,
value: 9,
categoryIndex: 1,
seriesIndex: 0
},
{
categoryValue: 15,
value: 6,
categoryIndex: 2,
seriesIndex: 0
},
{ categoryValue: 22, value: 7, categoryIndex: 3, seriesIndex: 0 }
]
}
];
var domain = axis.createDomain(
cartesianSeries,
ValueType.fromDescriptor({ text: true }),
false,
[]
);
// returns: [0, 1, 2, 3]
getCategoryValueType
此函数获取类别列的 ValueType。 如果该类型不存在,则默认值为 Text。
function getCategoryValueType(
data: any[],
axisType: ValueTypeDescriptor,
isScalar: boolean,
forcedScalarDomain: any[],
ensureDomain?: NumberRange
): number[];
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
var cartesianSeries = [
{
data: [
{ categoryValue: 7, value: 11, categoryIndex: 0, seriesIndex: 0 },
{
categoryValue: 9,
value: 9,
categoryIndex: 1,
seriesIndex: 0
},
{
categoryValue: 15,
value: 6,
categoryIndex: 2,
seriesIndex: 0
},
{ categoryValue: 22, value: 7, categoryIndex: 3, seriesIndex: 0 }
]
}
];
axis.getCategoryValueType(
cartesianSeries,
ValueType.fromDescriptor({ text: true }),
false,
[]
);
// returns: [0, 1, 2, 3]
createAxis
此函数创建一个包含刻度的 D3 轴。 可以垂直或水平,并且可以是日期/时间、数字或文本。
function createAxis(options: CreateAxisOptions): IAxisProperties;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
import { valueFormatter } from "powerbi-visuals-utils-formattingutils";
// ...
var dataPercent = [0.0, 0.33, 0.49];
var formatStringProp: powerbi.DataViewObjectPropertyIdentifier = {
objectName: "general",
propertyName: "formatString"
};
let metaDataColumnPercent: powerbi.DataViewMetadataColumn = {
displayName: "Column",
type: ValueType.fromDescriptor({ numeric: true }),
objects: {
general: {
formatString: "0 %"
}
}
};
var os = axis.createAxis({
pixelSpan: 100,
dataDomain: [dataPercent[0], dataPercent[2]],
metaDataColumn: metaDataColumnPercent,
formatString: valueFormatter.getFormatString(
metaDataColumnPercent,
formatStringProp
),
outerPadding: 0.5,
isScalar: true,
isVertical: true
});
applyCustomizedDomain
此函数设置自定义域,但在未设置任何内容时不会更改。
function applyCustomizedDomain(customizedDomain: any[], forcedDomain: any[]): any[];
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
let customizedDomain = [undefined, 20],
existingDomain = [0, 10];
axis.applyCustomizedDomain(customizedDomain, existingDomain);
// returns: {0:0, 1:20}
combineDomain
如果设置了其中一个值,则此函数会将强制域与实际域合并。 forcedDomain 处于第一优先级。 如果任何引用点需要,则扩展该域。
function combineDomain(
forcedDomain: any[],
domain: any[],
ensureDomain?: NumberRange
): any[];
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
let forcedYDomain = this.valueAxisProperties
? [this.valueAxisProperties["secStart"], this.valueAxisProperties["secEnd"]]
: null;
let xDomain = [minX, maxX];
axis.combineDomain(forcedYDomain, xDomain, ensureXDomain);
powerOfTen
此函数指示数字是否为 10 的幂。
function powerOfTen(d: any): boolean;
示例:
import { axis } from "powerbi-visuals-utils-chartutils";
// ...
axis.powerOfTen(10);
// returns: true
DataLabelManager
DataLabelManager 有助于创建和维护标签。 它使用锚点或矩形排列标签元素。 可以自动检测冲突以重新定位或隐藏元素。
DataLabelManager 类提供以下方法:
hideCollidedLabels
此方法根据标签大小和重叠排列画布上的标签位置和可见性。
function hideCollidedLabels(
viewport: IViewport,
data: any[],
layout: any,
addTransform: boolean = false
hideCollidedLabels?: boolean
): LabelEnabledDataPoint[];
示例:
let dataLabelManager = new DataLabelManager();
let filteredData = dataLabelManager.hideCollidedLabels(
this.viewport,
values,
labelLayout,
true,
true
);
IsValid
此静态方法检查提供的矩形是否有效,也就是它是否具有正宽度和高度。
function isValid(rect: IRect): boolean;
示例:
let rectangle = {
left: 150,
top: 130,
width: 120,
height: 110
};
DataLabelManager.isValid(rectangle);
// returns: true
DataLabelUtils
DataLabelUtils 提供用于操作数据标签的 utils。
该方法提供了以下函数、接口和类:
getLabelPrecision
此函数根据提供的格式计算精度。
function getLabelPrecision(precision: number, format: string): number;
getLabelFormattedText
此函数根据提供的格式返回格式精度。
function getLabelFormattedText(options: LabelFormattedTextOptions): string;
示例:
import { dataLabelUtils } from "powerbi-visuals-utils-chartutils";
// ...
let options: LabelFormattedTextOptions = {
text: "some text",
fontFamily: "sans",
fontSize: "15",
fontWeight: "normal"
};
dataLabelUtils.getLabelFormattedText(options);
enumerateDataLabels
此函数返回数据标签的 VisualObjectInstance。
function enumerateDataLabels(
options: VisualDataLabelsSettingsOptions
): VisualObjectInstance;
enumerateCategoryLabels
此函数将类别数据标签的 VisualObjectInstance 添加到枚举对象。
function enumerateCategoryLabels(
enumeration: VisualObjectInstanceEnumerationObject,
dataLabelsSettings: VisualDataLabelsSettings,
withFill: boolean,
isShowCategory: boolean = false,
fontSize?: number
): void;
createColumnFormatterCacheManager
此函数返回用于快速访问格式化标签的缓存管理器。
function createColumnFormatterCacheManager(): IColumnFormatterCacheManager;
示例:
import { dataLabelUtils } from "powerbi-visuals-utils-chartutils";
// ...
let value: number = 200000;
labelSettings.displayUnits = 1000000;
labelSettings.precision = 1;
let formattersCache = DataLabelUtils.createColumnFormatterCacheManager();
let formatter = formattersCache.getOrCreate(null, labelSettings);
let formattedValue = formatter.format(value);
// formattedValue == "0.2M"
图例服务
Legend 服务提供了帮助程序接口,用于创建和管理 Power BI 视觉对象的 Power BI 图例。
该模块提供了以下函数和接口:
createLegend
此帮助程序函数可简化 Power BI 自定义视觉对象图例的创建。
function createLegend(
legendParentElement: HTMLElement, // top visual element, container in which legend will be created
isScrollable: boolean = false, // indicates that legend could be scrollable or not
legendPosition: LegendPosition = LegendPosition.Top // Position of the legend inside of legendParentElement container
): ILegend;
示例:
public constructor(options: VisualConstructorOptions) {
this.visualInitOptions = options;
this.layers = [];
var element = this.element = options.element;
var viewport = this.currentViewport = options.viewport;
var hostServices = options.host;
//... some other init calls
this.legend = createLegend(
element,
true);
}
ILegend
此接口可实现创建图例所需的所有方法。
export interface ILegend {
getMargins(): IViewport;
isVisible(): boolean;
changeOrientation(orientation: LegendPosition): void; // processing legend orientation
getOrientation(): LegendPosition; // get information about current legend orientation
drawLegend(data: LegendData, viewport: IViewport); // all legend rendering code is placing here
/**
* Reset the legend by clearing it
*/
reset(): void;
}
drawLegend
此函数用给定的 SVG 文本属性来度量文本的高度。
function drawLegend(data: LegendData, viewport: IViewport): void;
示例:
private renderLegend(): void {
if (!this.isInteractive) {
let legendObjectProperties = this.data.legendObjectProperties;
if (legendObjectProperties) {
let legendData = this.data.legendData;
LegendData.update(legendData, legendObjectProperties);
let position = <string>legendObjectProperties[legendProps.position];
if (position)
this.legend.changeOrientation(LegendPosition[position]);
this.legend.drawLegend(legendData, this.parentViewport);
} else {
this.legend.changeOrientation(LegendPosition.Top);
this.legend.drawLegend({ dataPoints: [] }, this.parentViewport);
}
}
}