一、杂谈

微信分享图片的迷之bug，前一阵子接盘一个Hybrid App，分享要用原生的分享，搞了一阵子把微信分享搞上，测试又反馈了一个谜一样的Bug，我这边看Log打印了checkArgs fail, thumbData is invalid，google一番都说是图片不能超过32kb，在分享里面看到如下判断this.thumbData.length > '耀'，一时间没有反应过来。。。可是怎么压缩好哇，我参照官方Demo和AndroidUtilCode的按质量压缩方法，找出了下面的解决方案，供大家参考。

二、将网络图片加载到内存

保存到本地在操作真心感觉麻烦

public static byte[] getHtmlByteArray(final String url) {
	URL htmlUrl = null;
	InputStream inStream = null;
	try {
		htmlUrl = new URL(url);
		URLConnection connection = htmlUrl.openConnection();
		HttpURLConnection httpConnection = (HttpURLConnection) connection;
		int responseCode = httpConnection.getResponseCode();
		if (responseCode == HttpURLConnection.HTTP_OK) {
			inStream = httpConnection.getInputStream();
		}
	} catch (MalformedURLException e) {
		e.printStackTrace();
	} catch (IOException e) {
		e.printStackTrace();
	}
	// 将io流转为byte数组
	byte[] data = inputStreamToByte(inStream);
	if (data.length > '耀') {

    	// 转换为bitmap
    	Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
    
    	// 获取压缩后的byte数组
    	data = compressByQuality(bitmap, '耀', true);
    }
    return data;
}

三、将io流转为byte数组

public static byte[] inputStreamToByte(InputStream is) {
	try {
		ByteArrayOutputStream bytestream = new ByteArrayOutputStream();
		int ch;
		while ((ch = is.read()) != -1) {
			bytestream.write(ch);
		}
		byte imgdata[] = bytestream.toByteArray();
		bytestream.close();
		return imgdata;
	} catch (Exception e) {
		e.printStackTrace();
	}

	return null;
}

四、按质量压缩

/**
	* 按质量压缩图片
	*
	* @param src         bitmap图片
	* @param maxByteSize 最大字节数
	* @param recycle
	* @return
	*/
public static byte[] compressByQuality(final Bitmap src, final long maxByteSize, final boolean recycle) {
	ByteArrayOutputStream baos = new ByteArrayOutputStream();
	src.compress(CompressFormat.JPEG, 100, baos);
	byte[] bytes;
	if (baos.size() <= maxByteSize) {
		bytes = baos.toByteArray();
	} else {
		baos.reset();
		src.compress(CompressFormat.JPEG, 0, baos);
		if (baos.size() >= maxByteSize) {
			bytes = baos.toByteArray();
		} else {
			// find the best quality using binary search
			int st = 0;
			int end = 100;
			int mid = 0;
			while (st < end) {
				mid = (st + end) / 2;
				baos.reset();
				src.compress(CompressFormat.JPEG, mid, baos);
				int len = baos.size();
				if (len == maxByteSize) {
					break;
				} else if (len > maxByteSize) {
					end = mid - 1;
				} else {
					st = mid + 1;
				}
			}
			if (end == mid - 1) {
				baos.reset();
				src.compress(CompressFormat.JPEG, st, baos);
			}
			bytes = baos.toByteArray();
		}
	}
	if (recycle && !src.isRecycled()) src.recycle();
	return bytes;
}

五、微信分享

WXWebpageObject object = new WXWebpageObject();
object.webpageUrl = url;
WXMediaMessage wxMediaMessage = new WXMediaMessage(object);
// 标题
wxMediaMessage.title = title;
// 描述
wxMediaMessage.description = des.substring(0, 20);
// 图片
wxMediaMessage.thumbData = Util.getHtmlByteArray(image);
//构造一个Req
SendMessageToWX.Req req = new SendMessageToWX.Req();
req.transaction = String.valueOf(System.currentTimeMillis());
req.message = wxMediaMessage;
req.scene = SendMessageToWX.Req.WXSceneSession;
mIWXAPI.sendReq(req);

六、源码

WechatShareUtil类

https://github.com/sdwfqin/AndroidQuick