wechatShopUni/ec-canvas/ec-canvas.wxml

<canvas 
  type="2d" 
  class="ec-canvas" 
  canvas-id="{{ canvasId }}"
  bindinit="init"
  bindtouchstart="{{ onTouchStart }}"
  bindtouchmove="{{ onTouchMove }}"
  bindtouchend="{{ onTouchEnd }}"
></canvas>