//初始化一个 WXTextObject 对象，填写分享的文本内容
WXTextObject textObj = new WXTextObject();
textObj.text = text;
//用 WXTextObject 对象初始化一个 WXMediaMessage 对象
WXMediaMessage msg = new WXMediaMessage();
msg.mediaObject = textObj;
msg.description = text;
SendMessageToWX.Req req = new SendMessageToWX.Req();
req.transaction = buildTransaction("text");
req.message = msg;
req.scene = mTargetScene;
//调用api接口，发送数据到微信
api.sendReq(req);
示例代码项目里可以找到，具体实现如下：
private String buildTransaction(final String type) { return (type == null) ? String.valueOf(System.currentTimeMillis()) : type + System.currentTimeMillis(); }