reader/mixins/share.js

module.exports = Behavior({
  data: {},
  methods: {
    onShareAppMessage({
      from,
      target
    }) {
      if (from == 'button') {
        let video = target.dataset.info
        console.log(video);
        const promise = new Promise(resolve => {
          this.creatShare(video).then(res => {
            resolve(res)
          })
        })
        return {
          title: '请欣赏我的课文朗读作品，点赞+评论。',
          path: `/pages/index/index?readId=${video.id}&uid=${wx.getStorageSync('uid')}`,
          imageUrl: video.coverImg,
          promise
        }
      } else {
        return {
          title: '课文朗读，从未如此有趣。',
          path: `/pages/index/index?&uid=${wx.getStorageSync('uid')}`,
          imageUrl: 'http://reader-wx.ai160.com/images/reader/v3/shareContent.png'
        }
      }
    },
    creatShare(video) {
      console.log(video);
      return new Promise((resolve, reject) => {
        let context = wx.createSelectorQuery();
        context
          .select('#share')
          .fields({
            node: true,
            size: true
          }).exec((res) => {
            const canvas = res[0].node;
            const ctx = canvas.getContext('2d');
            const dpr = wx.getSystemInfoSync().pixelRatio;
            canvas.width = res[0].width * dpr;
            canvas.height = res[0].height * dpr;
            ctx.scale(dpr, dpr);
            ctx.font = '14px PingFang';
            let pic = canvas.createImage();
            pic.src = video.userRead.coverImg; //可以是本地，也可以是网络图片
            pic.onload = () => {
              ctx.drawImage(pic, 0, 0, 375, 211);
            }
            let peiyin = canvas.createImage();
            peiyin.src = '/static/peiyin.jpg';
            peiyin.onload = () => {
              ctx.drawImage(peiyin, 0, 211, 375, 89);
              //分享
              let fx = canvas.createImage();
              fx.src = '/static/share.png'
              fx.onload = () => {
                ctx.drawImage(fx, 12, 220, 20, 20)
                ctx.fillText('分享', 36, 238)
                // 收藏，一个一个渲染
                let sc = canvas.createImage();
                sc.src = '/static/no_collect.png'
                sc.onload = () => {
                  ctx.drawImage(sc, 110, 220, 19, 19)
                  ctx.fillText('收藏', 134, 238)
                  //点赞
                  let dz = canvas.createImage();
                  dz.src = video.isLike ? '/static/heart_colored.png' : '/static/heart.png'
                  dz.onload = () => {
                    ctx.drawImage(dz, 228, 222, 22, 22)
                    ctx.fillText(video.userRead.likeAmount, 254, 238)
                    // 评论
                    let pl = canvas.createImage();
                    pl.src = '/static/comment.png'
                    pl.onload = () => {
                      ctx.drawImage(pl, 318, 222, 22, 22)
                      ctx.fillText(video.userRead.commentAmount, 340, 238)
                      setTimeout(() => {
                        wx.canvasToTempFilePath({
                          canvas: canvas,
                          success(res) {
                            resolve({
                              title: '请欣赏我的课文朗读作品，点赞+评论。',
                              path: `/pages/index?readId=${video.id}&uid=${wx.getStorageSync('uid')}`,
                              imageUrl: res.tempFilePath
                            })
                          },
                          fail(res) {
                            reject()
                          }
                        }, this)
                      }, 500)
                    }
                  }
                }
              }
            }
          })
      })
    },
  }
})