String appId = KeyConstants.WEIXIN_APP_ID;//开发者平台ID
IWXAPI api = WXAPIFactory.createWXAPI(this, appId, false);
if (api.isWXAppInstalled()) {
    JumpToBizProfile.Req req = new JumpToBizProfile.Req();
    req.toUserName = "gh_c40962be4ada"; // 公众号原始ID
    req.extMsg = "http://weixin.qq.com/r/Wy3QyJ-Ez8Kwrdur93hJ";
    req.profileType = JumpToBizProfile.JUMP_TO_HARD_WARE_BIZ_PROFILE; // 普通公众号
    api.sendReq(req);
}else{
    Toast.makeText(this, "微信未安装", Toast.LENGTH_SHORT).show();
}