利用微信内置 javascript 对象 WeixinJSBridge 分享到朋友圈图片不能显示问题求解

分享后那个小图显示不出来

<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<meta charset="utf-8">
<meta content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0" name="viewport">
<meta content="yes" name="apple-mobile-web-app-capable">
<meta content="black" name="apple-mobile-web-app-status-bar-style">
<meta content="telephone=no" name="format-detection">
<title>分享测试</title>

<style>
*{ margin: 0; padding: 0;}
img{ max-width: 100%;}
</style>
</head>
<body>
<img src="" alt="">

<script>
//var imgUrl=encodeURI("http://images.51vv.com/upload/sod/artist/mobile/W/五月天/五月天2.jpg");//分享的图片
var imgUrl=encodeURI("http://images.51vv.com/upload/sod/artist/photos/14/08/1408343949131.jpg");

var lineLink =document.URL;
var descContent = '分享概况';
var shareTitle ='分享标题';
var appid = '';

var share={
shareFriend:function(){
WeixinJSBridge.invoke('sendAppMessage',{
"appid": appid,
"img_url": imgUrl,
"img_width": "200",
"img_height": "200",
"link": lineLink,
"desc": descContent,
"title": shareTitle
}, function(res) {
//_report('send_msg', res.err_msg);
})
},
//分享到朋友圈
shareTimeline:function() {
alert(imgUrl);
WeixinJSBridge.invoke('shareTimeline',{//
"img_url": "http://images.51vv.com/upload/sod/artist/photos/14/08/1408343949131.jpg",
"img_width": "200",
"img_height": "200",
"link": lineLink,
"desc": descContent,
"title": shareTitle
}, function(res) {
//_report('timeline', res.err_msg);
});
}
}

document.addEventListener('WeixinJSBridgeReady', function onBridgeReady() {//

//发送给好友
WeixinJSBridge.on('menu:share:appmessage', function(argv){
share.shareFriend();
});
//分享到朋友圈
WeixinJSBridge.on('menu:share:timeline', function(argv){
share.shareTimeline();
});

}, false);

</script>

</body>
</html>