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ahille
Regular Visitor

How to structure data to then pass to d3.hierachy (or d3.treemap directly) in custom visual

Hi, I'm fairly new to developing custom visuals. I've gone through a few tutorials and messed around moving simple d3 visuals to power bi, and am now trying to make a custom treemap visual based on this d3 treemap. I can make it work if I include the data directly in the visual, but I'm struggling in making sense how to structure the data from power bi into a format that can be used by d3.hierarchy then passed to d3.treemap, or used directly by d3.treemap.

 

I think the matrix data view mapping would be most appropriate, as it's a hierachical structure? Unfortunately, I haven't been able to find any tutorials or sample custom visuals using the matrix data view, and I find the information on the Understand data view mapping page somewhat limited.

 

I've posted my visual.ts code below, and would greatly appreciate any help / pointing in the direction of relevant documention/tutorials/examples!

 

 

"use strict";

import "core-js/stable";
import "./../style/visual.less";
import powerbi from "powerbi-visuals-api";
import VisualConstructorOptions = powerbi.extensibility.visual.VisualConstructorOptions;
import VisualUpdateOptions = powerbi.extensibility.visual.VisualUpdateOptions;
import IVisual = powerbi.extensibility.visual.IVisual;
import EnumerateVisualObjectInstancesOptions = powerbi.EnumerateVisualObjectInstancesOptions;
import VisualObjectInstance = powerbi.VisualObjectInstance;
import DataView = powerbi.DataView;
import VisualObjectInstanceEnumerationObject = powerbi.VisualObjectInstanceEnumerationObject;
import { VisualSettings } from "./settings";
import * as d3 from 'd3';
import { values } from "d3";
import { getMeasureIndexOfRole } from "powerbi-visuals-utils-dataviewutils/lib/dataRoleHelper";



interface Finn {
    children: {
        name: string;
        children: {
            name: string;
            group: string;
            value: number;
            colname: string;
        }[];
        colname: string;
    }[];
    name: string;
}

export class Visual implements IVisual {
    private target: HTMLElement;
    private settings: VisualSettings;
    private container: d3.Selection<HTMLDivElement, any, HTMLDivElement, any>;

    constructor(options: VisualConstructorOptions) {
        console.log('Visual constructor', options);
        this.target = options.element;
        this.container = d3.select(this.target)
            .append('div')
            .attr('id', 'my_dataviz');
    }

    public update(options: VisualUpdateOptions) {
        //console.log('Visual update', options);
        //this.settings = Visual.parseSettings(options && options.dataViews && options.dataViews[0]);
       // this.container.selectAll('*').remove();
        //let dataViews = options.dataViews;
        
        var margin = { top: 10, right: 30, bottom: 30, left: 60 },
            width = options.viewport.width - margin.left - margin.right,
            height = options.viewport.height - margin.top - margin.bottom;

        var svg = this.container
            .append("svg")
            .attr("width", width + margin.left + margin.right)
            .attr("height", height + margin.top + margin.bottom)
            .append("g")
            .attr("transform",
                "translate(" + margin.left + "," + margin.top + ")");
        //data
        let data: Finn = {
            "children": [
                {
                    "name": "boss1",
                    "children": [
                        {
                            "name": "mister_a",
                            "group": "A",
                            "value": 28,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_b",
                            "group": "A",
                            "value": 19,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_c",
                            "group": "C",
                            "value": 18,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_d",
                            "group": "C",
                            "value": 19,
                            "colname": "level3"
                        }
                    ],
                    "colname": "level2"
                },
                {
                    "name": "boss2",
                    "children": [
                        {
                            "name": "mister_e",
                            "group": "C",
                            "value": 14,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_f",
                            "group": "A",
                            "value": 11,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_g",
                            "group": "B",
                            "value": 15,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_h",
                            "group": "B",
                            "value": 16,
                            "colname": "level3"
                        }
                    ],
                    "colname": "level2"
                },
                {
                    "name": "boss3",
                    "children": [
                        {
                            "name": "mister_i",
                            "group": "B",
                            "value": 10,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_j",
                            "group": "A",
                            "value": 13,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_k",
                            "group": "A",
                            "value": 13,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_l",
                            "group": "D",
                            "value": 25,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_m",
                            "group": "D",
                            "value": 16,
                            "colname": "level3"
                        },
                        {
                            "name": "mister_n",
                            "group": "D",
                            "value": 28,
                            "colname": "level3"
                        }
                    ],
                    "colname": "level2"
                }
            ],
            "name": "CEO"
        }
        // read json data
        // d3.json("https://raw.githubusercontent.com/holtzy/D3-graph-gallery/master/DATA/data_dendrogram_full.json", function (data) {

        // Give the data to this cluster layout:
        var root = d3.hierarchy(data).sum(function (d) { return (<any>d).value }) // Here the size of each leave is given in the 'value' field in input data

        // Then d3.treemap computes the position of each element of the hierarchy
        d3.treemap()
            .size([width, height])
            .padding(2)
            (root)

        // use this information to add rectangles:
        svg
            .selectAll("rect")
            .data(root.leaves())
            .enter()
            .append("rect")
            .attr('x', function (d) { return (<any>d).x0; })
            .attr('y', function (d) { return (<any>d).y0; })
            .attr('width', function (d) { return (<any>d).x1 - (<any>d).x0; })
            .attr('height', function (d) { return (<any>d).y1 - (<any>d).y0; })
            .style("stroke", "black")
            .style("fill", "slateblue")

        // and to add the text labels
        svg
            .selectAll("text")
            .data(root.leaves())
            .enter()
            .append("text")
            .attr("x", function (d) { return (<any>d).x0 + 5 })    // +10 to adjust position (more right)
            .attr("y", function (d) { return (<any>d).y0 + 20 })    // +20 to adjust position (lower)
            .text(function (d) { return d.data.name })
            .attr("font-size", "15px")
            .attr("fill", "white")
    }
    //)
//}

    private static parseSettings(dataView: DataView): VisualSettings {
    return VisualSettings.parse(dataView) as VisualSettings;
}

    /**
     * This function gets called for each of the objects defined in the capabilities files and allows you to select which of the
     * objects and properties you want to expose to the users in the property pane.
     *
     */
    public enumerateObjectInstances(options: EnumerateVisualObjectInstancesOptions): VisualObjectInstance[] | VisualObjectInstanceEnumerationObject {
    return VisualSettings.enumerateObjectInstances(this.settings || VisualSettings.getDefault(), options);
}
}

 

 

1 REPLY 1
Anonymous
Not applicable

Hi @ahille,

Perhaps you can use local storage API to export the source data and target data structure for analysis, then you can add some processing in your code to do formatting operations.

Local Storage API 
Regards,
Xiaoxin Sheng

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