Purpose

The Flutter ECR Plugin (ecrlib) provides cross‑platform integration for Android and iOS applications. It wraps the native SDKs to expose Dart APIs, enabling developers to build POS apps in Flutter without directly handling native socket communication.

Prerequisites

Flutter SDK 2.0+
ecrlib package added to pubspec.yaml
Native Android/iOS SDKs configured in the project

Installation

# pubspec.yaml
dependencies:
  ecrlib:
    path: ./plugins/ecrlib

TCP/IP Connection Example

import 'package:ecrlib/ecrlib.dart';

final tcp = TcpConnect();
int status = await tcp.connectTCP("192.168.0.102", 8888, "ECR001");

tcp.doTransaction(
  reqData: requestString,
  txnType: 0, // Purchase
  signature: signatureData,
  listener: ComEventListener(
    onEvent: (event) => print("Event: $event"),
    onSuccess: (response) => print("Success: $response"),
    onFailure: (error, code) => print("Error: $error"),
  ),
);

tcp.disconnect();

App‑to‑App Connection Example (Android Only)

final a2a = AppToAppConnect();
int? status = await a2a.connect("ECR001");

a2a.doTransaction(
  reqData: requestString,
  txnType: 0, // Purchase
  signature: signatureData,
  listener: ComEventListenerss(
    onEvent: (event) => print("Event: $event"),
    onSuccess: (response) => print("Success: $response"),
    onFailure: (error, code) => print("Error: $error"),
  ),
);

Transaction Flow

connectTCP() / connect() → Register (17) → Start Session (18) → doTransaction() → ComEventListener

⚠️ Legacy vs Adapter Separation

Legacy ECR integrations require Register (17) and Start Session (18).
Adapter/Middleware integrations (Local REST API, Cloud REST API) do not require these steps.

Request and Response Details

When performing a transaction, include:

Date (ddMMyyHHmmss)
ECR Reference Number
Amount (Integer in halalas, e.g., 100 = SAR 1.00)

Responses return:

Response Code (Approved/Failed)
Approval Code
Receipt Data

Transaction Type Codes

Code	Transaction Type
0	Purchase
1	Purchase with Naqd/Cashback
2	Refund
3	Authorization
4	Purchase Advice (Full)
5	Purchase Advice (Partial)
6	Auth Extension
7	Auth Void
9	Cash Advance
10	Reconciliation
11	Reversal
15	Bill Payment
17	Register (Legacy only)
18	Start Session (Legacy only)
19	End Session
23	Duplicate / Previous Txn
24	Check Status
25	Health Check