安卓微信支付

1.统一下单

/**
     * 构造支付统一下单参数列表
     * @param app_id
     * @return
     */
    public static Map<String, String> buildOrderParamMap(String mch_id,String subject, String price, String app_id) {
        //判断是否有网络连接
        String ip ="";
        if(NetWorkUtil.isNetworkConnected(MyApplication.getInstance())){
            NetWorkUtil.NetType apnNet = NetWorkUtil.getAPNType(MyApplication.getInstance());
            if(apnNet == NetWorkUtil.NetType.WIFI){
                ip = NetWorkUtil.getIpAddress();
            } else {
                ip = NetWorkUtil.getLocalIpAddress();
            }
        } else {
            ToastUtil.showMessage(MyApplication.getInstance(),"当前无网络");
            return null;
        }

        Map<String, String> keyValues = new HashMap<String, String>();
        //appid
        keyValues.put("appid", app_id);
        //商户号
        keyValues.put("mch_id",mch_id);
        //随机字符串
        keyValues.put("nonce_str", RandomUtil.generateString(32));
        //商品描述
        keyValues.put("body",subject);
        //商户订单号
        keyValues.put("out_trade_no",getOutTradeNo());
        //总金额
        keyValues.put("total_fee",price);
        //通知地址
        keyValues.put("notify_url",PAYONOTIFY);
        //交易类型
        keyValues.put("trade_type","APP");
        //终端ip
        keyValues.put("spbill_create_ip",ip);

        return keyValues;
    }

/**
     * 对支付参数信息进行签名
     *
     * @param map
     *            待签名授权信息
     *
     * @return
     */
    public static String getSign(Map<String, String> map, String rsaKey) {
        List<String> keys = new ArrayList<String>(map.keySet());
        // key排序
        Collections.sort(keys);

        StringBuilder authInfo = new StringBuilder();
        for (int i = 0; i < keys.size() - 1; i++) {
            String key = keys.get(i);
            String value = map.get(key);
            authInfo.append(buildKeyValue(key, value, false));
            authInfo.append("&");
        }

        String tailKey = keys.get(keys.size() - 1);
        String tailValue = map.get(tailKey);
        authInfo.append(buildKeyValue(tailKey, tailValue, false));

        String oriSign = authInfo.toString() + "&key=" + rsaKey;
        Log.i("weixin_param",oriSign);
        oriSign = Encrypt.MD5(oriSign.getBytes()).toUpperCase();
        Log.i("weixin_sign",oriSign);
        String encodedSign = "";

        try {
            encodedSign = URLEncoder.encode(oriSign, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return encodedSign;
    }

/**
     * 构造支付统一下单参数列表
     * @param app_id
     * @return
     */
    public static Map<String, String> buildOrderParamMap(String mch_id,String subject, String price, String app_id) {
        //判断是否有网络连接
        String ip ="";
        if(NetWorkUtil.isNetworkConnected(MyApplication.getInstance())){
            NetWorkUtil.NetType apnNet = NetWorkUtil.getAPNType(MyApplication.getInstance());
            if(apnNet == NetWorkUtil.NetType.WIFI){
                ip = NetWorkUtil.getIpAddress();
            } else {
                ip = NetWorkUtil.getLocalIpAddress();
            }
        } else {
            ToastUtil.showMessage(MyApplication.getInstance(),"当前无网络");
            return null;
        }

        Map<String, String> keyValues = new HashMap<String, String>();
        //appid
        keyValues.put("appid", app_id);
        //商户号
        keyValues.put("mch_id",mch_id);
        //随机字符串
        keyValues.put("nonce_str", RandomUtil.generateString(32));
        //商品描述
        keyValues.put("body",subject);
        //商户订单号
        keyValues.put("out_trade_no",getOutTradeNo());
        //总金额
        keyValues.put("total_fee",price);
        //通知地址
        keyValues.put("notify_url",PAYONOTIFY);
        //交易类型
        keyValues.put("trade_type","APP");
        //终端ip
        keyValues.put("spbill_create_ip",ip);

        return keyValues;
    }

/**
     * 要求外部订单号必须唯一。
     * @return
     */
    private static String getOutTradeNo() {
        SimpleDateFormat format = new SimpleDateFormat("MMddHHmmss", Locale.getDefault());
        Date date = new Date();
        String key = format.format(date);

        Random r = new Random();
        key = key + r.nextInt();
        key = key.substring(0, 15);
        return key;
    }

public interface WeiXinOrderService {

    @POST("pay/unifiedorder")
    Observable<String> getOrder(@Body String body);
}

首先拼接参数签名，再将参数和签名sign按照微信支付要求的xml以body的形式传递给统一下单url，成功之后，微信支付会返回xml数据，个人用的是retrofit+rxandroid网络事件框架，所以在onNext中得到这个xml，接着开始发起支付调用pay();

2.发起支付

/**
 * 发起支付请求
 */
public void pay(Map<String,String> map){
    Map<String,String> keyValues = new HashMap<>();
    keyValues.put("appid",map.get("appid"));
    keyValues.put("partnerid",Constant.WEIXIN_CUSTOMER_ID);
    keyValues.put("prepayid",map.get("prepay_id"));
    keyValues.put("package","Sign=WXPay");
    keyValues.put("noncestr",map.get("nonce_str"));
    String timestamp = System.currentTimeMillis()+"";
    keyValues.put("timestamp",timestamp);

//签名
    String sign = WeiXinTool.getSign(keyValues, Constant.WEIXIN_APP_KEY);

    PayReq req = new PayReq();
    req.appId = map.get("appid");
    req.prepayId = map.get("prepay_id");
    req.nonceStr = map.get("nonce_str");
    req.sign = sign;
    //req.extData = "app data"; // optional
    req.timeStamp = timestamp; //这里注意，不能再写System.currentTimeMillis()，因为时间已经不一样，否则会报签名错误
    req.packageValue = "Sign=WXPay";
    req.partnerId = Constant.WEIXIN_CUSTOMER_ID;
    //Toast.makeText(PayActivity.this, "正常调起支付", Toast.LENGTH_SHORT).show();
    // 在支付之前，如果应用没有注册到微信，应该先调用IWXMsg.registerApp将应用注册到微信
//这里只用使用微信demo中提交request即可
    MyApplication.getInstance().getApi().sendReq(req);

}

其实统一订单应该放在服务器端处理！