微信小程序实现分享商品海报功能

initPic(){
 this.handleNetImg('网络图片地址').then((res)=>{
 this.bgdSrc =res.path;//保存这个临时图片路径
 }
}
//生成临时图片
handleNetImg(imagePath) {
 return new Promise((resolve, reject) => {
 uni.getImageInfo({
 src: imagePath,
 suess: function (res) {
 resolve(res);
 }
 });
 });
},

<button open-type="share">点击分享</button>
<button @click="getPhotosAlbumAuth">保存本地</button>
<view class="canvas-box">
 <canvas canvas-id='mycanvas'></canvas>
</view>

createShareGoods(){
 uni.showLoading({
 title:'正在生成中...'
 })
 var ctx = uni.createCanvasContext('mycanvas', this);
 ctx.drawImage(this.bgdSrc, 0, 0, 300, 240); //画背景图
 ctx.drawImage(this.itemPic, 0, 0, 400, 400, 30, 45, 140, 140);//画商品图片
 ctx.drawImage(this.qrcode, 0, 0, 400, 400, 225, 5, 100, 100);//画二维码,这边可以变成小程序码
 //现价
 ctx.setFillStyle('#E80013');
 ctx.setFontSize(18);
 ctx.fillText('这边可以写一些说明之类的', 180, 100);
 ctx.setFillStyle('#E80013');
 ctx.setFontSize(18);
 ctx.fillText('这边可以写一些说明之类的', 100, 100);
 //开始画画完后生成新的临时图片地址
 ctx.draw(false, () => {
 setTimeout(()=>{
 uni.canvasToTempFilePath({
 canvasId: 'mycanvas',
 suess: (res) => {
 uni.hideLoading();
 this.picTempUrl=res.tempFilePath;
 }
 });
 }, 300);
 })
},

/
  分享页面到微信好友
 /
onShareAppMessage(){
 return {
 title: '限时特卖'+this.name,
 path: 'pages/index/index?data=这边可以传一些ID啥的',
 imageUrl: this.picTempUrl
 }
},

//获取手机相册权限
getPhotosAlbumAuth(){
 uni.getSetting({
 suess:(res)=> {
 if (!res.authSetting['scope.writePhotosAlbum']) {
 uni.authorize({
 scope: 'scope.writePhotosAlbum',
 suess:()=> {
 this.saveImage();
 }
 })
 } else {
 this.saveImage();
 }
 }
 })
},
//保存海报
saveImage(){
 uni.saveImageToPhotosAlbum({
 filePath: this.picTempUrl,
 suess: (data)=> {
 uni.showToast({
 title: "图片保存成功",
 icon: "suess",
 mask: true
 })
 },
 plete: () => {
 this.posterStatus=false;
 }
 })
},