reader/components/createPoster/index.js

Component({
    properties: {},
    data: {
        state: true,
        img: ''
    },
    methods: {
        open() {
            this.setData({
                state: true
            })
        },
        closeMediaBox() {
            this.setData({
                state: false
            })
        },
        savePoster() {
            const query = wx.createSelectorQuery().in(this);
            query
                .select('#cavansId')
                .fields({
                    node: true,
                    size: true
                }).exec(async (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;
                    let pic = canvas.createImage();
                    pic.src = 'https://reader-wx.ai160.com/images/reader/pay/shareBg.jpg'
                    pic.onload = () => {
                        ctx.drawImage(pic, 0, 0, 646, 959);
                        let pl = canvas.createImage();
                        pl.src = 'https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket=gQEs8TwAAAAAAAAAAS5odHRwOi8vd2VpeGluLnFxLmNvbS9xLzAyZzR0ZTE2T2M5N1UxYURaYU5CY1QAAgSHoQplAwQgHAAA'
                        pl.onload = () => {
                            ctx.drawImage(pl, 25, 747, 173, 173)
                        }
                    }
                })
        }
    }
})