PayReq req =new PayReq();
    req.appId = payData.get("appId");
    req.partnerId = payData.get("mchId"); 
    req.packageValue=payData.get("package");
    req.prepayId = payData.get("prepayId");
    req.nonceStr = payData.get("noncestr");
    req.timeStamp = payData.get("timestamp");
    req.sign = payData.get("sign");
    IWXAPI api = WXAPIFactory.createWXAPI(application,req.appId);
// 唤起支付处理页面
    api.sendReq(req);

调用api无法唤起微信，sdk也没有任何提示信息，这个很难定位问题的原因，微信sdk能增加toast提示吗？