如何在angular2 / Ionic2项目中导入leaflet-heatmap插件？

Question

我试图将leaflet-heatmap插件导入angular2 / Ionic2项目，但没有取得多大成功。 我在堆栈溢出中找到了一些关于如何在角度项目中导入传单的解释，并且它完美地工作。 但是，我在尝试包含热图（图层）插件时遇到了很多困难。

任何帮助将非常感激。

对插件的引用：

https://github.com/pa7/heatmap.js

https://www.patrick-wied.at/static/heatmapjs/example-heatmap-leaflet.html

干杯

Answer 1

嘿，我是为个人使用而做的，但随意使用它

https://gist.github.com/rpdiss/5e63816e30a1fb0ec252be0fcceb6078

import L from "leaflet";
import 'heatmap.js';

/**
 * author: Rafał Piekarski
 * email: noopek@gmail.com
 * this was made only cuz of need
 * for personal usage feel free to email
 * me with some improvements
 *
 * remember to npm/yarn heatmap.js and leaflet !
 * gl bois!
 */

declare var window: {
  h337: {
    create: Function,
    register: Function,
  }
};


export namespace HeatOverlayRP {
  export interface HTMLElementEx extends HTMLElement {
    _leaflet_pos?: L.Point;
  }

  export interface HeatData {
    latlng: L.LatLng;
    radius: any;
  }

  export interface HeatPoint {
    x: Number;
    y: Number;
    radius?: Number;
  }

  export interface HeatOverlayRP {

    constructor(options?: L.LayerOptions);

    addTo(map: L.Map | L.LayerGroup): this;

    onAdd(map: L.Map): this;

    onRemove(map: L.Map): this;

    setData(data: Array<HeatData>);
  }

  export class HeatOverlayRP extends L.Layer implements HeatOverlayRP {
    private heatData: Array<HeatData>;
    private el: HTMLElement;
    private min: Number;
    private max: Number;
    private cfg: any;
    private map: L.Map;
    private x: Number;
    private y: Number;
    private heatmap;

    constructor(config: L.LayerOptions) {
      super();
      this.cfg = config;
      this.el = L.DomUtil.create('div', 'leaflet-zoom-hide');
      this.heatData = [];
      this.min = 0;
      this.max = 1;
      this.cfg.container = this.el;
    }

    public onAdd(map: L.Map) {
      let size = map.getSize();

      this.map = map;

      this.x = size.x;
      this.y = size.y;

      this.el.style.width = `${size.x}px`;
      this.el.style.height = `${size.y}px`;
      this.el.style.position = 'absolute';

      this.map.getPanes().overlayPane.appendChild(this.el);
      if (!this.heatmap) {
        this.heatmap = window.h337.create(this.cfg);
      }

      map.on('moveend', this.reset, this);
      this.draw();
      return this;
    }

    public addTo(map: L.Map) {
      map.addLayer(this);
      return this;
    }

    public onRemove(map: L.Map) {
      map.getPanes().overlayPane.removeChild(this.el);
      map.off('moveend', this.reset, this);
      return this;
    }

    private draw() {
      if (!this.map) return;

      let mapPane: HTMLElementEx = this.map.getPanes().mapPane;
      let point = mapPane._leaflet_pos;

      this.el.style[CSS_TRANSFORM] = `translate(${-Math.round(point.x)}px, ${-Math.round(point.y)}px)`;

      this.update();
    }

    private update() {
      let bounds: L.LatLngBounds = this.map.getBounds();
      let generatedData = {max: this.max, min: this.min, data: []};
      let zoom = this.map.getZoom();
      let scale = Math.pow(2, zoom);

      if (this.heatData.length == 0) {
        if (this.heatmap) {
          this.heatmap.setData(generatedData);
        }
        return;
      }

      let latLngPoints = [];
      let radiusMultiplier: any = this.cfg.scaleRadius ? scale : 1;
      let localMax: number = 0;
      let localMin: number = 0;
      let valueField = this.cfg.valueField;
      let len = this.heatData.length;

      while (len--) {
        let entry = this.heatData[len];
        let value = entry[valueField];
        let latlng = entry.latlng;

        if (!bounds.contains(latlng)) {
          continue;
        }

        localMax = Math.max(value, localMax);
        localMin = Math.min(value, localMin);

        let point: L.Point = this.map.latLngToContainerPoint(latlng);
        let latlngPoint: HeatPoint = {x: Math.round(point.x), y: Math.round(point.y)};
        latlngPoint[valueField] = value;

        let radius;

        if (entry.radius) {
          radius = entry.radius * radiusMultiplier;
        } else {
          radius = (this.cfg.radius || 2) * radiusMultiplier;
        }

        console.log(radius, this.cfg.radius, radiusMultiplier);

        latlngPoint.radius = radius;
        latLngPoints.push(latlngPoint);
      }

      if (this.cfg.useLocalExtrema) {
        generatedData.max = localMax;
        generatedData.min = localMin;
      }

      generatedData.data = latLngPoints;

      this.heatmap.setData(generatedData);
    }

    setData(data: Array<HeatData>) {

      let len = data.length;
      let d = [];

      while (len--) {
        d.push(data[len]);
      }

      this.heatData = d;

      this.draw();
    }

    private reset() {
      let size = this.map.getSize();
      if (this.x !== size.x || this.y !== size.y) {
        this.x = size.x;
        this.y = size.y;

        this.el.style.width = this.x + 'px';
        this.el.style.height = this.y + 'px';

        this.heatmap._renderer.setDimensions(this.x, this.y);
      }
      this.draw();
    }
  }

  export const CSS_TRANSFORM = (() => {
    let div = document.createElement('div');
    let props = [
      'transform',
      'WebkitTransform',
      'MozTransform',
      'OTransform',
      'msTransform'
    ];
    for (let i = 0; i < props.length; i++) {
      const prop = props[i];
      if (div.style[prop] !== undefined) {
        return prop;
      }
    }
    return props[0];
  })()
}