突出显示 Power BI 视觉对象中的数据点
本文介绍了如何在 Power BI 视觉对象中突出显示数据。
默认情况下，选择某个元素后，dataView对象中的 values 数组会被筛选为仅显示所选的值。 筛选 values 数组后，页面上的所有其他视觉对象仅显示所选数据。
如果将 capabilities.json 文件中的 supportsHighlight 属性设置为 true，则会生成未经筛选的完整 values 数组和 highlights 数组。 highlights 数组的长度与 values 数组的长度相同，并且任何未选定的值都设置为 null。 启用此属性后，会将 values 数组与 highlights 数组进行比较来突出显示视觉对象中的相应数据。
在此示例中，请注意：
- 如果不支持突出显示，所选项将是
values数组中唯一的值，也是数据视图中唯一显示的条形。 - 如果有突出显示支持，所有值都将在
values数组中。highlights数组包含未突出显示元素的null值。 所有条形都显示在数据视图中，突出显示的条形采用不同的颜色。
还可以选择多项和采用部分突出显示。 突出显示的值显示在数据视图中。
注意
表数据视图映射不支持突出显示功能。
用分类数据视图映射功能突出显示数据点
对于具有分类数据视图映射的视觉对象，请将 "supportsHighlight": true 添加到 capabilities.json 文件中。 例如：
{
"dataRoles": [
{
"displayName": "Category",
"name": "category",
"kind": "Grouping"
},
{
"displayName": "Value",
"name": "value",
"kind": "Measure"
}
],
"dataViewMappings": [
{
"categorical": {
"categories": {
"for": {
"in": "category"
}
},
"values": {
"for": {
"in": "value"
}
}
}
}
],
"supportsHighlight": true
}
删除不必要的代码后，默认视觉对象源代码如以下示例所示：
"use strict";
// ... default imports list
import { FormattingSettingsService } from "powerbi-visuals-utils-formattingmodel";
import DataViewCategorical = powerbi.DataViewCategorical;
import DataViewCategoryColumn = powerbi.DataViewCategoryColumn;
import PrimitiveValue = powerbi.PrimitiveValue;
import DataViewValueColumn = powerbi.DataViewValueColumn;
import { VisualFormattingSettingsModel } from "./settings";
export class Visual implements IVisual {
private target: HTMLElement;
private formattingSettings: VisualFormattingSettingsModel;
private formattingSettingsService: FormattingSettingsService;
constructor(options: VisualConstructorOptions) {
console.log('Visual constructor', options);
this.formattingSettingsService = new FormattingSettingsService();
this.target = options.element;
this.host = options.host;
}
public update(options: VisualUpdateOptions) {
this.formattingSettings = this.formattingSettingsService.populateFormattingSettingsModel(VisualFormattingSettingsModel, options.dataViews);
console.log('Visual update', options);
}
// Returns properties pane formatting model content hierarchies, properties and latest formatting values, Then populate properties pane.
// This method is called once every time we open properties pane or when the user edit any format property.
public getFormattingModel(): powerbi.visuals.FormattingModel {
return this.formattingSettingsService.buildFormattingModel(this.formattingSettings);
}
}
导入所需接口，以处理来自 Power BI 的数据：
import DataViewCategorical = powerbi.DataViewCategorical;
import DataViewCategoryColumn = powerbi.DataViewCategoryColumn;
import PrimitiveValue = powerbi.PrimitiveValue;
import DataViewValueColumn = powerbi.DataViewValueColumn;
为类别值创建根 div 元素：
export class Visual implements IVisual {
private target: HTMLElement;
private formattingSettings: VisualFormattingSettingsModel;
private formattingSettingsService: FormattingSettingsService;
private div: HTMLDivElement; // new property
constructor(options: VisualConstructorOptions) {
console.log('Visual constructor', options);
this.formattingSettingsService = new FormattingSettingsService();
this.target = options.element;
this.host = options.host;
// create div element
this.div = document.createElement("div");
this.div.classList.add("vertical");
this.target.appendChild(this.div);
}
// ...
}
在呈现新数据之前清除 div 元素的内容：
// ...
public update(options: VisualUpdateOptions) {
this.formattingSettings = this.formattingSettingsService.populateFormattingSettingsModel(VisualFormattingSettingsModel, options.dataViews);
console.log('Visual update', options);
while (this.div.firstChild) {
this.div.removeChild(this.div.firstChild);
}
// ...
}
从 dataView 对象获取类别和度量值：
public update(options: VisualUpdateOptions) {
this.formattingSettings = this.formattingSettingsService.populateFormattingSettingsModel(VisualFormattingSettingsModel, options.dataViews);
console.log('Visual update', options);
while (this.div.firstChild) {
this.div.removeChild(this.div.firstChild);
}
const dataView: DataView = options.dataViews[0];
const categoricalDataView: DataViewCategorical = dataView.categorical;
const categories: DataViewCategoryColumn = categoricalDataView.categories[0];
const categoryValues = categories.values;
const measures: DataViewValueColumn = categoricalDataView.values[0];
const measureValues = measures.values;
const measureHighlights = measures.highlights;
// ...
}
其中 categoryValues 是类别值数组，measureValues 是度量值数组，measureHighlights 是值的突出显示部分。
注意
如果 measureHighlights 属性的值小于 categoryValues 属性的值，则部分突出显示该值。
枚举 categoryValues 数组并获取相应的值和突出显示的内容：
// ...
const measureHighlights = measures.highlights;
categoryValues.forEach((category: PrimitiveValue, index: number) => {
const measureValue = measureValues[index];
const measureHighlight = measureHighlights && measureHighlights[index] ? measureHighlights[index] : null;
console.log(category, measureValue, measureHighlight);
});
创建 div 和 p 元素，用于显示和直观呈现视觉对象 DOM 中的数据视图值：
categoryValues.forEach((category: PrimitiveValue, index: number) => {
const measureValue = measureValues[index];
const measureHighlight = measureHighlights && measureHighlights[index] ? measureHighlights[index] : null;
console.log(category, measureValue, measureHighlight);
// div element. it contains elements to display values and visualize value as progress bar
let div = document.createElement("div");
div.classList.add("horizontal");
this.div.appendChild(div);
// div element to visualize value of measure
let barValue = document.createElement("div");
barValue.style.width = +measureValue * 10 + "px";
barValue.style.display = "flex";
barValue.classList.add("value");
// element to display category value
let bp = document.createElement("p");
bp.innerText = category.toString();
// div element to visualize highlight of measure
let barHighlight = document.createElement("div");
barHighlight.classList.add("highlight")
barHighlight.style.backgroundColor = "blue";
barHighlight.style.width = +measureHighlight * 10 + "px";
// element to display highlighted value of measure
let p = document.createElement("p");
p.innerText = `${measureHighlight}/${measureValue}`;
barHighlight.appendChild(bp);
div.appendChild(barValue);
barValue.appendChild(barHighlight);
div.appendChild(p);
});
应用所需的元素样式，以使用 flexbox 并定义 div 元素的颜色：
div.vertical {
display: flex;
flex-direction: column;
}
div.horizontal {
display: flex;
flex-direction: row;
}
div.highlight {
background-color: blue
}
div.value {
background-color: red;
display: flex;
}
结果呈现为视觉对象的以下视图：
用矩阵数据视图映射突出显示数据点
对于具有矩阵数据视图映射的视觉对象，请将 "supportsHighlight": true 添加到 capabilities.json 文件中。 例如：
{
"dataRoles": [
{
"displayName": "Columns",
"name": "columns",
"kind": "Grouping"
},
{
"displayName": "Rows",
"name": "rows",
"kind": "Grouping"
},
{
"displayName": "Value",
"name": "value",
"kind": "Measure"
}
],
"dataViewMappings": [
{
"matrix": {
"columns": {
"for": {
"in": "columns"
}
},
"rows": {
"for": {
"in": "rows"
}
},
"values": {
"for": {
"in": "value"
}
}
}
}
],
"supportsHighlight": true
}
以下示例数据用于创建矩阵数据视图映射的层次结构：
| 行 1 | 行 2 | 行 3 | Column1 | Column2 | Column3 | 值 |
|---|---|---|---|---|---|---|
| R1 | R11 | R111 | C1 | C11 | C111 | 1 |
| R1 | R11 | R112 | C1 | C11 | C112 | 2 |
| R1 | R11 | R113 | C1 | C11 | C113 | 3 |
| R1 | R12 | R121 | C1 | C12 | C121 | 4 |
| R1 | R12 | R122 | C1 | C12 | C122 | 5 |
| R1 | R12 | R123 | C1 | C12 | C123 | 6 |
| R1 | R13 | R131 | C1 | C13 | C131 | 7 |
| R1 | R13 | R132 | C1 | C13 | C132 | 8 |
| R1 | R13 | R133 | C1 | C13 | C133 | 9 |
| R2 | R21 | R211 | C2 | C21 | C211 | 10 |
| R2 | R21 | R212 | C2 | C21 | C212 | 11 |
| R2 | R21 | R213 | C2 | C21 | C213 | 12 |
| R2 | R22 | R221 | C2 | C22 | C221 | 13 |
| R2 | R22 | R222 | C2 | C22 | C222 | 14 |
| R2 | R22 | R223 | C2 | C22 | C223 | 16 |
| R2 | R23 | R231 | C2 | C23 | C231 | 17 |
| R2 | R23 | R232 | C2 | C23 | C232 | 18 |
| R2 | R23 | R233 | C2 | C23 | C233 | 19 |
创建默认视觉对象项目，并应用 capabilities.json 文件的示例。
删除不必要的代码后，默认视觉对象源代码如以下示例所示：
"use strict";
// ... default imports
import { FormattingSettingsService } from "powerbi-visuals-utils-formattingmodel";
import { VisualFormattingSettingsModel } from "./settings";
export class Visual implements IVisual {
private target: HTMLElement;
private formattingSettings: VisualFormattingSettingsModel;
private formattingSettingsService: FormattingSettingsService;
constructor(options: VisualConstructorOptions) {
console.log('Visual constructor', options);
this.formattingSettingsService = new FormattingSettingsService();
this.target = options.element;
this.host = options.host;
}
public update(options: VisualUpdateOptions) {
this.formattingSettings = this.formattingSettingsService.populateFormattingSettingsModel(VisualFormattingSettingsModel, options.dataViews);
console.log('Visual update', options);
}
/**
* Returns properties pane formatting model content hierarchies, properties and latest formatting values, Then populate properties pane.
* This method is called once every time we open properties pane or when the user edit any format property.
*/
public getFormattingModel(): powerbi.visuals.FormattingModel {
return this.formattingSettingsService.buildFormattingModel(this.formattingSettings);
}
}
导入所需的接口，以处理来自 Power BI 的数据：
import DataViewMatrix = powerbi.DataViewMatrix;
import DataViewMatrixNode = powerbi.DataViewMatrixNode;
import DataViewHierarchyLevel = powerbi.DataViewHierarchyLevel;
创建两个 div 元素，用于视觉对象布局：
constructor(options: VisualConstructorOptions) {
// ...
this.rowsDiv = document.createElement("div");
this.target.appendChild(this.rowsDiv);
this.colsDiv = document.createElement("div");
this.target.appendChild(this.colsDiv);
this.target.style.overflowY = "auto";
}
检查 update 方法中的数据，确保视觉对象可获取数据：
public update(options: VisualUpdateOptions) {
this.formattingSettings = this.formattingSettingsService.populateFormattingSettingsModel(VisualFormattingSettingsModel, options.dataViews);
console.log('Visual update', options);
const dataView: DataView = options.dataViews[0];
const matrixDataView: DataViewMatrix = dataView.matrix;
if (!matrixDataView ||
!matrixDataView.columns ||
!matrixDataView.rows ) {
return
}
// ...
}
在呈现新数据之前清除 div 元素的内容：
public update(options: VisualUpdateOptions) {
// ...
// remove old elements
// to better performance use D3js pattern:
// https://d3js.org/#enter-exit
while (this.rowsDiv.firstChild) {
this.rowsDiv.removeChild(this.rowsDiv.firstChild);
}
const prow = document.createElement("p");
prow.innerText = "Rows";
this.rowsDiv.appendChild(prow);
while (this.colsDiv.firstChild) {
this.colsDiv.removeChild(this.colsDiv.firstChild);
}
const pcol = document.createElement("p");
pcol.innerText = "Columns";
this.colsDiv.appendChild(pcol);
// ...
}
创建 treeWalker 函数来遍历矩阵数据结构：
public update(options: VisualUpdateOptions) {
// ...
const treeWalker = (matrixNode: DataViewMatrixNode, index: number, levels: DataViewHierarchyLevel[], div: HTMLDivElement) => {
}
// ...
}
其中 matrixNode 是当前节点，levels 是此层次结构级别的元数据列，div 是子 HTML 元素的父元素。
treeWalker 是递归函数，需要为文本创建 div 元素和 p（用作标头），并为节点的子元素调用函数：
public update(options: VisualUpdateOptions) {
// ...
const treeWalker = (matrixNode: DataViewMatrixNode, index: number, levels: DataViewHierarchyLevel[], div: HTMLDivElement) => {
// ...
if (matrixNode.children) {
const childDiv = document.createElement("div");
childDiv.classList.add("vertical");
div.appendChild(childDiv);
const p = document.createElement("p");
const level = levels[matrixNode.level]; // get current level column metadata from current node
p.innerText = level.sources[level.sources.length - 1].displayName; // get column name from metadata
childDiv.appendChild(p); // add paragraph element to div element
matrixNode.children.forEach((node, index) => treeWalker(node, levels, childDiv, ++levelIndex));
}
}
// ...
}
为矩阵数据视图结构的列和行的根元素调用函数：
public update(options: VisualUpdateOptions) {
// ...
const treeWalker = (matrixNode: DataViewMatrixNode, index: number, levels: DataViewHierarchyLevel[], div: HTMLDivElement) => {
// ...
}
// ...
// remove old elements
// ...
// ...
const rowRoot: DataViewMatrixNode = matrixDataView.rows.root;
rowRoot.children.forEach((node) => treeWalker(node, matrixDataView.rows.levels, this.rowsDiv));
const colRoot = matrixDataView.columns.root;
colRoot.children.forEach((node) => treeWalker(node, matrixDataView.columns.levels, this.colsDiv));
}
为节点生成 selectionID，并创建按钮以显示节点：
public update(options: VisualUpdateOptions) {
// ...
const treeWalker = (matrixNode: DataViewMatrixNode, index: number, levels: DataViewHierarchyLevel[], div: HTMLDivElement) => {
const selectionID: ISelectionID = this.host.createSelectionIdBuilder()
.withMatrixNode(matrixNode, levels)
.createSelectionId();
let nodeBlock = document.createElement("button");
nodeBlock.innerText = matrixNode.value.toString();
nodeBlock.addEventListener("click", (event) => {
// call select method in the selection manager
this.selectionManager.select(selectionID);
});
nodeBlock.addEventListener("contextmenu", (event) => {
// call showContextMenu method to display context menu on the visual
this.selectionManager.showContextMenu(selectionID, {
x: event.clientX,
y: event.clientY
});
event.preventDefault();
});
// ...
}
// ...
}
突出显示的主要步骤是另外创建一个值数组。
终端节点的对象具有值数组的两个属性，即 value 和 highlight：
JSON.stringify(options.dataViews[0].matrix.rows.root.children[0].children[0].children[0], null, " ");
{
"level": 2,
"levelValues": [
{
"value": "R233",
"levelSourceIndex": 0
}
],
"value": "R233",
"identity": {
"identityIndex": 2
},
"values": {
"0": {
"value": null,
"highlight": null
},
"1": {
"value": 19,
"highlight": 19
}
}
}
其中 value 表示节点的值，不应用其他视觉对象的选定内容，而 highlight 指示突出显示的数据部分。
注意
如果 highlight 的值小于 value 的值，则部分突出显示 value。
添加用于处理节点的 values 数组（如果呈现）的代码：
public update(options: VisualUpdateOptions) {
// ...
const treeWalker = (matrixNode: DataViewMatrixNode, index: number, levels: DataViewHierarchyLevel[], div: HTMLDivElement) => {
// ...
if (matrixNode.values) {
const sumOfValues = Object.keys(matrixNode.values) // get key property of object (value are 0 to N)
.map(key => +matrixNode.values[key].value) // convert key property to number
.reduce((prev, curr) => prev + curr) // sum of values
let sumOfHighlights = sumOfValues;
sumOfHighlights = Object.keys(matrixNode.values) // get key property of object (value are 0 to N)
.map(key => matrixNode.values[key].highlight ? +matrixNode.values[key].highlight : null ) // convert key property to number if it exists
.reduce((prev, curr) => curr ? prev + curr : null) // convert key property to number
// create div container for value and highlighted value
const vals = document.createElement("div");
vals.classList.add("vertical")
vals.classList.replace("vertical", "horizontal");
// create paragraph element for label
const highlighted = document.createElement("p");
// Display complete value and highlighted value
highlighted.innerText = `${sumOfHighlights}/${sumOfValues}`;
// create div container for value
const valueDiv = document.createElement("div");
valueDiv.style.width = sumOfValues * 10 + "px";
valueDiv.classList.add("value");
// create div container for highlighted values
const highlightsDiv = document.createElement("div");
highlightsDiv.style.width = sumOfHighlights * 10 + "px";
highlightsDiv.classList.add("highlight");
valueDiv.appendChild(highlightsDiv);
// append button and paragraph to div containers to parent div
vals.appendChild(nodeBlock);
vals.appendChild(valueDiv);
vals.appendChild(highlighted);
div.appendChild(vals);
} else {
div.appendChild(nodeBlock);
}
if (matrixNode.children) {
// ...
}
}
// ...
}
呈现的结果是带有按钮和值的视觉对象，如 highlighted value/default value。
