uni.sendWithSystem分享图片不显示，代码如下：
let temppath = '';
uni.downloadFile({
url:'https://vgcenterpic.oss-cn-beijing.aliyuncs.com/pic/K1561031393476.jpg',
success: function (res) {
if (res.statusCode === 200) {
temppath = res.tempFilePath;
}
}
})
// #ifdef APP-PLUS
plus.share.sendWithSystem({
pictures:temppath,
type:'image'
})
// #endif
