折腾了一天，终于搞定了微信支付，总结一下。首先从服务器端获取prepareid,Andorid 端再根据这个prepareid二次签名。
服务器端：
从官网上下载DEMO，Demo中只有JsAPi,Micro,Native。没有APP的，那怎么办呢？模仿着jsAPi的自己写一个。
第一步：配置WxPay.Config.php
const APPID = 'wx004d72dd9aab9cc5'; const MCHID = '1293496801'; const KEY = 'zcvnoasdfasnvu93n320dvndsf98nlds';
第二步：替换cert
const SSLCERT_PATH = '../cert/apiclient_cert.pem'; const SSLKEY_PATH = '../cert/apiclient_key.pem';
第三步：统一下单
<?php
ini_set('date.timezone','Asia/Shanghai');
require_once "../lib/WxPay.Api.php";
//①、获取用户openid
//$tools = new JsApiPay();
//$openId = $tools->GetOpenid();
//②、统一下单
$input = new WxPayUnifiedOrder();
$input->SetBody("test");
$input->SetAttach("test");
$input->SetOut_trade_no(WxPayConfig::MCHID.date("YmdHis"));
$input->SetTotal_fee("1");
$input->SetTime_start(date("YmdHis"));
$input->SetTime_expire(date("YmdHis", time() + 600));
$input->SetGoods_tag("test");
$input->SetNotify_url("http://paysdk.weixin.qq.com/example/notify.php");
$input->SetTrade_type("APP");
//$input->SetOpenid($openId);
$order = WxPayApi::unifiedOrder($input);
$parameters = json_encode($order);
echo $parameters;
Android端
private void weixinPay() {
final IWXAPI msgApi = WXAPIFactory.createWXAPI(getActivity(), null);
msgApi.registerApp(Constants.APP_ID);
String url = "http://192.168.208.34/WxpayAPI/example/appapi.php";
Toast.makeText(getActivity(), "获取订单中...", Toast.LENGTH_SHORT).show();
HttpUtil.sendJsonRequest(HttpRequest.HttpMethod.GET, url, null, new HttpRequestCallBack<Object>() {
@Override
public void onSuccessed(ResponseInfo<Object> responseInfo) {
Log.e("Josen", responseInfo.result.toString());
prePayBean = new Gson().fromJson(responseInfo.result.toString(), PrePayBean.class);
PayReq req = new PayReq();
req.appId = prePayBean.getAppid();
req.partnerId = prePayBean.getMch_id();
req.prepayId = prePayBean.getPrepay_id();
req.nonceStr = RandomString.getRandomString(20);
req.timeStamp = String.valueOf(System.currentTimeMillis()/1000);
req.packageValue = "Sign=WXPay";
String string = "app
+req.nonceStr+"&package="+req.packageValue+"&partnerid="
+req.partnerId+"&prepay
+req.timeStamp+"&key="+Constants.APP_KEY;
String sign = MD5.getMessageDigest(string.getBytes());
req.sign = sign.toUpperCase();
msgApi.sendReq(req);
}
@Override
public void onFailed(HttpException exception, String reason) {
}
}, 0);
}