APP接入微信支付

1.在build.gradle文件中加入如下依賴

    //微信支付
    implementation 'com.tencent.mm.opensdk:wechat-sdk-android-without-mta:5.4.3'

2.在當前包名下新建一個wxapi的包，新建一個 WXPayEntryActivity 

public class WXPayEntryActivity extends AppCompatActivity implements IWXAPIEventHandler {
    private IWXAPI api;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        api = WXAPIFactory.createWXAPI(this, "輸入你的AppID");
        api.handleIntent(getIntent(), this);
    }

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        setIntent(intent);
        api.handleIntent(intent, this);
    }

    @Override
    public void onReq(BaseReq req) {
    }

    @Override
    public void onResp(BaseResp resp) {
        if (resp.getType() == ConstantsAPI.COMMAND_PAY_BY_WX) {
            switch (resp.errCode) {
                case 0://成功
                    Toast.makeText(this, getString(R.string.pay_success), Toast.LENGTH_SHORT).show();
                    EventBus.getDefault().post(Constants.WECHAT_PAY_SUCCESS);
                    break;
                case -1://錯誤
                    Toast.makeText(this, getString(R.string.pay_failed), Toast.LENGTH_SHORT).show();
                    EventBus.getDefault().post(Constants.WECHAT_PAY_FAILED);
                    break;
                case -2://用戶取消
                    Toast.makeText(this, getString(R.string.pay_cancel), Toast.LENGTH_SHORT).show();
                    EventBus.getDefault().post(Constants.WECHAT_PAY_CANCEL);
                    break;
                default:
                    break;
            }
            finish();
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        api.detach();
    }
}

3.清單文件配置activity

<activity android:name="你的包名.wxapi.WXPayEntryActivity"
            android:exported="true"
            android:launchMode="singleTop"
            android:screenOrientation="portrait"/>

4.在當前包名下新建一個wxpay的包,新建一個WXPay的類

/**
 * 調起微信支付
 *
 * @author Administrator
 */
public class WXPay {

    private static IWXAPI msgApi;

    private static void registerApp(Context context, String appid) {
        msgApi = WXAPIFactory.createWXAPI(context, appid);
        msgApi.registerApp(appid);
    }


    /**
     * 自定義方法開始傳入參數調起微信
     * @param context context
     * @param appid 你的AppID
     * @param prepay 通過服務端返回的數據解析的WXPayInfo類
     */
    public static void pay(Context context, String appid, WXPayInfo prepay) {
        if (msgApi == null) {
            registerApp(context, appid);
        }
        if (!msgApi.isWXAppInstalled()) {
            Toast.makeText(context, R.string.uninstall_wechat, Toast.LENGTH_LONG).show();
            return;
        }
        PayReq request = new PayReq();
        if (prepay != null) {
            request.appId = appid;
            request.partnerId = prepay.getPartnerid();
            request.prepayId = prepay.getPrepayid();
            request.packageValue = Constants.WEIXIN_PACKAGE_VALUE;
            request.nonceStr = prepay.getNoncestr();
            request.timeStamp = "" + prepay.getTimestamp();
            request.sign = prepay.getSign();
            msgApi.sendReq(request);
        } else {
            Toast.makeText(context, R.string.params_null, Toast.LENGTH_LONG).show();
        }
    }
}

5.最後開始調用

WXPay.pay(this, "你的AppID", "服務端返回的json解析以後的bean");