<button bind:tap="drawCanvas" type="primary">drawCanvas</button>
    <image src="{{ imageSrc }}" />

正常情况下，点击按钮，图片会在新的坐标绘制，但是第二次点击直接就是用不了了。

// index.js
const defaultAvatarUrl = 'https://mmbiz.qpic.cn/mmbiz/icTdbqWNOwNRna42FI242Lcia07jQodd2FJGIYQfG0LAJGFxM4FbnQP6yfMxBgJ0F3YRqJCJ1aPAK2dQagdusBZg/0'


Page({
  data: {
    times: 0,
    logs: [],
    imageSrc: ''
  },
  async drawCanvas() {
    let times = this.data.times;
    let log = (msg, ...args) => {
      this.setData({ logs: [msg, ...this.data.logs] })
      console.log(msg, ...args)
    }


    async function loadImage(can, src) {
      return new Promise((resolve, reject) => {
        const img = can.createImage()
        const timer = setTimeout(() => {
          log('image load timeout! force continue! size = ' + img.width + 'x' + img.height)
          resolve(img)
        }, 500)
        img.onload = () => {
          log('image loaded!', img.width, img.height)
          resolve(img)
          clearTimeout(timer)
        }
        img.onerror = (error) => {
          log('Failed to load image:', component.imageUrl, error);
          reject(error);
          clearTimeout(timer)
        };
        img.src = src
      })
    }


    try {
      this.setData({ times: times + 1 })


      console.log('create canvas')
      const can = wx.createOffscreenCanvas({
        width: 800,
        height: 480,
        type: '2d'
      })


      log('get ctx')
      /** @type {CanvasRenderingContext2D} */
      const ctx = can.getContext('2d')


      log('fill canvas')
      ctx.fillStyle = '#ee3300'
      ctx.fillRect(0, 0, 800, 480)
      const image = await loadImage(can, defaultAvatarUrl)
      ctx.drawImage(image, (100 * times) % 800, 40, 300, 400)


      ctx.fillStyle = '#3003ff'
      ctx.fillRect(10, 60, 800, 60)


      log('saving image')
      const out = await wx.canvasToTempFilePath({ canvas: can })
      this.setData({ imageSrc: out.tempFilePath })


      log('OK!')
    } catch (err) {
      error('draw err', err)
    }
  }
})

翻到一个旧的帖子发现好像一直没fix，就这样摆烂了么？

https://developers.weixin.qq.com/community/develop/doc/000e66a1b2c98836858ea46d55b800