<canvas
  a:if="{{id}}"
  type="{{type}}"
  id="{{id}}"
  class="f-canvas"
  width="{{width}}"
  height="{{height}}"
  onTap="click"
  onTouchStart="touchStart"
  onTouchMove="touchMove"
  onTouchEnd="touchEnd"
  onReady="onCanvasReady"
/>