javascript - D3 svg 组件不可调整大小

Question

我正在使用 Angular 4 创建一个应用程序和 D3 .当我创建 svg通过将组件注入(inject)另一个组件，从组件内部的组件，它显示组件，但调整大小和移动功能不起作用(即使调整大小和移动光标也不会在悬停时显示)。
如果我使用相同的组件并导航到具有路由的组件，则调整大小和移动功能会起作用。知道为什么。

以下是我使用的组件。

import { Component, OnInit } from '@angular/core';
import * as d3 from 'd3';

@Component({
  selector: 'app-function-box',
  templateUrl: './function-box.component.html',
  styleUrls: ['./function-box.component.css']
})
export class FunctionBoxComponent implements OnInit {

  constructor() { }

  ngOnInit() {
  }

  w = 500;
  h = 350;
  r = 120;

  width = 200;
  height = 100;
  dragbarw = 10;

  svg = d3.select("body").append("svg")
    .attr("width", this.w)
    .attr("height", this.h);

  newg = this.svg.append("g")
    .data([{x: 400, y: 100}]); //position

  dragrect = this.newg.append("rect")
    .attr("id", "active")
    .attr("x", (d) => { return d.x;  })
    .attr("y", (d) => { return d.y; })
    .attr("height", this.height)
    .attr("width", this.width)
    .attr("fill-opacity", .5)
    .attr("cursor", "move")
    .call(d3.drag()
      .on("drag", this.dragmove.bind(this)));

  dragbarleft = this.newg.append("rect")
    .attr("x", (d) => { return d.x - (this.dragbarw/2); })
    .attr("y", (d) => { return d.y + (this.dragbarw/2); })
    .attr("height", this.height - this.dragbarw)
    .attr("id", "dragleft")
    .attr("width", this.dragbarw)
    .attr("fill", "lightblue")
    .attr("fill-opacity", .5)
    .attr("cursor", "ew-resize")
    .call(d3.drag()
      .on("drag", this.ldragresize.bind(this)));

  dragbarright = this.newg.append("rect")
    .attr("x", (d) => { return d.x + this.width - (this.dragbarw/2); })
    .attr("y", (d) => { return d.y + (this.dragbarw/2); })
    .attr("id", "dragright")
    .attr("height", this.height - this.dragbarw)
    .attr("width", this.dragbarw)
    .attr("fill", "lightblue")
    .attr("fill-opacity", .5)
    .attr("cursor", "ew-resize")
    .call(d3.drag()
      .on("drag", this.rdragresize.bind(this)));

  dragbartop = this.newg.append("rect")
    .attr("x", (d) => { return d.x + (this.dragbarw/2);})
    .attr("y", (d) => { return d.y - (this.dragbarw/2); })
    .attr("height", this.dragbarw)
    .attr("id", "dragleft")
    .attr("width", this.width - this.dragbarw)
    .attr("fill", "lightgreen")
    .attr("fill-opacity", .5)
    .attr("cursor", "ns-resize")
    .call(d3.drag()
      .on("drag", this.tdragresize));

  dragbarbottom = this.newg.append("rect")
    .attr("x", (d) => { return d.x + (this.dragbarw/2); })
    .attr("y", (d) => { return d.y + this.height - (this.dragbarw/2); })
    .attr("id", "dragright")
    .attr("height", this.dragbarw)
    .attr("width", this.width - this.dragbarw)
    .attr("fill", "lightgreen")
    .attr("fill-opacity", .5)
    .attr("cursor", "ns-resize")
    .call(d3.drag()
      .on("drag", this.bdragresize.bind(this)));

  dragmove(d) {

    this.dragrect
      .attr("x", d.x = Math.max(0, Math.min(this.w - this.width, d3.event.x)));
    this.dragbarleft
      .attr("x", (d) => { return d.x - (this.dragbarw/2); });
    this.dragbarright
      .attr("x", (d) => { return d.x +this.width - (this.dragbarw/2); });
    this.dragbartop
      .attr("x", (d) => { return d.x + (this.dragbarw/2); });
    this.dragbarbottom
      .attr("x", (d) => { return d.x + (this.dragbarw/2); })

    this.dragrect
      .attr("y", d.y = Math.max(0, Math.min(this.h - this.height, d3.event.y)));
    this.dragbarleft
      .attr("y", (d) => { return d.y + (this.dragbarw/2); });
    this.dragbarright
      .attr("y", (d) => { return d.y + (this.dragbarw/2); });
    this.dragbartop
      .attr("y", (d) => { return d.y - (this.dragbarw/2); });
    this.dragbarbottom
      .attr("y", (d) => { return d.y + this.height - (this.dragbarw/2); });

  }

  ldragresize(d) {
    let oldx = d.x;
    //Max x on the right is x + width - dragbarw
    //Max x on the left is 0 - (dragbarw/2)
    d.x = Math.max(0, Math.min(d.x + this.width - (this.dragbarw / 2), d3.event.x));
    this.width = this.width + (oldx - d.x);
    this.dragbarleft
      .attr("x", (d) => { return d.x - (this.dragbarw / 2); });

    this.dragrect
      .attr("x", (d) => { return d.x; })
      .attr("width", this.width);

    this.dragbartop
      .attr("x", (d) => { return d.x + (this.dragbarw/2); })
      .attr("width", this.width - this.dragbarw)
    this.dragbarbottom
      .attr("x", (d) => { return d.x + (this.dragbarw/2); })
      .attr("width", this.width - this.dragbarw)
  };

  rdragresize(d) {
    //Max x on the left is x - width
    //Max x on the right is width of screen + (dragbarw/2)
    let dragx = Math.max(d.x + (this.dragbarw/2), Math.min(this.w, d.x + this.width + d3.event.dx));

    //recalculate width
    this.width = dragx - d.x;

    //move the right drag handle
    this.dragbarright
      .attr("x", (d) => { return dragx - (this.dragbarw/2) });

    //resize the drag rectangle
    //as we are only resizing from the right, the x coordinate does not need to change
    this.dragrect
      .attr("width", this.width);
    this.dragbartop
      .attr("width", this.width - this.dragbarw)
    this.dragbarbottom
      .attr("width", this.width - this.dragbarw)
  }

  tdragresize(d) {

    let oldy = d.y;
    //Max x on the right is x + width - dragbarw
    //Max x on the left is 0 - (dragbarw/2)
    d.y = Math.max(0, Math.min(d.y + this.height - (this.dragbarw / 2), d3.event.y));
    this.height = this.height + (oldy - d.y);
    this.dragbartop
      .attr("y", (d) => { return d.y - (this.dragbarw / 2); });

    this.dragrect
      .attr("y", (d) => { return d.y; })
      .attr("height", this.height);

    this.dragbarleft
      .attr("y", (d) => { return d.y + (this.dragbarw/2); })
      .attr("height", this.height - this.dragbarw);
    this.dragbarright
      .attr("y", (d) => { return d.y + (this.dragbarw/2); })
      .attr("height", this.height - this.dragbarw);

  }

  bdragresize(d) {
    //Max x on the left is x - width
    //Max x on the right is width of screen + (dragbarw/2)
    let dragy = Math.max(d.y + (this.dragbarw/2), Math.min(this.h, d.y + this.height + d3.event.dy));

    //recalculate width
    this.height = dragy - d.y;

    //move the right drag handle
    this.dragbarbottom
      .attr("y", (d) => { return dragy - (this.dragbarw/2) });

    //resize the drag rectangle
    //as we are only resizing from the right, the x coordinate does not need to change
    this.dragrect
      .attr("height", this.height);
    this.dragbarleft
      .attr("height", this.height - this.dragbarw);
    this.dragbarright
      .attr("height", this.height - this.dragbarw);
  }
}

Answer 1

可以使用 ViewChild 回答您的问题在 Angular 中访问子组件、指令或 DOM 元素。

如果给定组件是您的子组件，那么您可以将一些引用变量添加到您的 html 代码中，如下所示(此处为 #chartbar)

<div #chartbar class="someclass"></div>

现在您需要在子组件中使用 ViewChild

import { Component, OnInit, ViewChild, ElementRef} from '@angular/core';  //Imported ViewChild, ElementRef
import * as d3 from 'd3';

@Component({
  selector: 'app-function-box',
  templateUrl: './function-box.component.html',
  styleUrls: ['./function-box.component.css']
})
export class FunctionBoxComponent implements OnInit {
  @ViewChild('chartbar') private chartContainer: ElementRef;  //Provider defined here

  constructor() { }

  ngOnInit() {
  }

  w = 500;
  h = 350;
  r = 120;

  const element = that.chartContainer.nativeElement;     //To use DOM element of html
  width = 200;
  height = 100;
  dragbarw = 10;

  svg = d3.select(element).append("svg")          //select DOM element instead of body
    .attr("width", this.w)
    .attr("height", this.h);

调整大小你会得到很好的选择here .