svg circle - Can't bind to cx since it isn't a known native property

JavascriptAngularTypescriptAngular2 Directives

Javascript Problem Overview


I need to do a progress arc based on the calculated percentage, I have created a custom directive to access the svg attributes from the user, while updating that in my template, I am getting the following error:

> Can't bind to 'cx' since it isn't a known native property
Can't bind to 'cy' since it isn't a known native property

etc..

I am getting these sorts of errors for all the svg attributes.

Below is my code in jade:

progress-arc([size]="200", [strokeWidth]="20", [stroke]="red", [complete]="0.8")

Below is my directive code:

import {Component,Input,AfterViewInit} from '@angular/core';

@Component({
  selector:'progress-arc',
  template:`
   <svg height="100" width="100">
      <circle fill="white"
          cx="{{parsedSize/2}}"
          cy="{{parsedSize/2}}"
          r="{{radius}}"
          stroke="{{stroke}}"
          stroke-width="{{strokeWidthCapped}}"
          stroke-dasharray="{{circumference}}"
          stroke-dashoffset="{{(1 - parsedComplete) * circumference}}"/>
  </svg>`,
  providers: [],
  directives: []
})
export class ProgressArc implements AfterViewInit {
 @Input('size') size:string;
 @Input('strokeWidth') strokeWidth:string;
 @Input('stroke') stroke:string;
  @Input('complete') complete:string;
  parsedStrokeWidth:number;
  parsedSize:number;
  parsedComplete:number;
  strokeWidthCapped:number;
  radius:number;
  circumference:number;

  ngAfterViewInit() {
    this.parsedSize = parseFloat(this.size);
    this.parsedStrokeWidth = parseFloat(this.strokeWidth);
    this.parsedComplete = parseFloat(this.complete);
    this.strokeWidthCapped = Math.min(this.parsedStrokeWidth, this.parsedSize / 2 - 1);
    this.radius = Math.max((this.parsedSize - this.strokeWidthCapped) / 2 - 1, 0);
    this.circumference = 2 * Math.PI * this.radius;
  }
}

Can someone tell me where I am going wrong?

Javascript Solutions


Solution 1 - Javascript

In order to bind to SVG element attributes in Angular, you must prefix them with attr:

For your circle this will be:

<svg height="100" width="100">
      <circle fill="white"
          [attr.cx]="parsedSize/2"
          [attr.cy]="parsedSize/2"
          [attr.r]="radius"
          [attr.stroke]="stroke"
          [attr.stroke-width]="strokeWidthCapped"
          [attr.stroke-dasharray]="circumference"
          [attr.stroke-dashoffset]="(1 - parsedComplete) * circumference"/>
</svg>

I am not entirely sure if it should be [attr.stroke-width] or [attr.strokeWidth], but give it a shot.

You need to use the attr prefix when the attribute has no property associated

Solution 2 - Javascript

Just thought I'd chime in if anyone is still using AngularJS. Use the ng-attr- prefix for attributes to interpolate:

 <svg height="100" width="100">
  <circle fill="white"
      cx="{{parsedSize/2}}"
      cy="{{parsedSize/2}}"
      r="{{radius}}"
      stroke="{{stroke}}"
      stroke-width="{{strokeWidthCapped}}"
      stroke-dasharray="{{circumference}}"
      stroke-dashoffset="{{(1 - parsedComplete) * circumference}}"/>

Becomes:

 <svg height="100" width="100">
  <circle fill="white"
      ng-attr-cx="{{parsedSize/2}}"
      ng-attr-cy="{{parsedSize/2}}"
      ng-attr-r="{{radius}}"
      ng-attr-stroke="{{stroke}}"
      ng-attr-stroke-width="{{strokeWidthCapped}}"
      ng-attr-stroke-dasharray="{{circumference}}"
      ng-attr-stroke-dashoffset="{{(1 - parsedComplete) * circumference}}"/>

Note that you keep the curly braces in this case.

Attributions

All content for this solution is sourced from the original question on Stackoverflow.

The content on this page is licensed under the Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license.

Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionSharmile MurugarajView Question on Stackoverflow
Solution 1 - JavascriptPoul KruijtView Answer on Stackoverflow
Solution 2 - JavascriptAdam MuraiView Answer on Stackoverflow