Signature_pad nao risca na tela

Ionic Framework
#1

Estou usando o npm install --save signature_pad

Após tudo instalado nao risca na tela do celular.

<ion-buttons slot="end">

  <ion-button color="light" expand="full" [disabled]="isCanvasBlank()" (click)="save()"> Save</ion-button>

  <ion-button color="light" expand="full" (click)="undo()"> Undo</ion-button>

  <ion-button color="light" expand="full" (click)="clear()"> Clear</ion-button>

</ion-buttons>

<ion-title>

  Signature Pad

</ion-title>

<div>

  <canvas class="signature-pad-canvas" #canvas width="900" height="400" style="touch-action: none;"></canvas>

</div>