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README.md

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 ![flutter-banner](https://github.com/Adyen/adyen-flutter/assets/13377878/6ca10143-9f75-43c6-bf6e-99011b09dd64)
 # Adyen Flutter (alpha)
+
+**This package is an alpha version. Please take into consideration that breaking changes could occur in future versions.**   
+
+Adyen Flutter provides you with the building blocks to create a checkout experience for your shoppers, allowing them to pay using the payment method of their choice.
+The building blocks support Android and iOS.
+
+You can integrate in two ways:
+
+- Drop-in: A wrapper for the native iOS and Android Adyen Drop-in - an all-in-one solution, the quickest way to accept payments in your app.
+- Card component: A wrapper for the native iOS and Android Adyen card components - A dedicated card widget, allowing card payments in your app.
+
+![preview](https://github.com/Adyen/adyen-android/assets/9079915/e6e18a07-b30f-41f0-b7ef-701b20e2e339)
+
+## Prerequisites
+
+For the integration into your app a [Client key](https://docs.adyen.com/development-resources/client-side-authentication#get-your-client-key) is required. Please be aware that you should not communicate with the Adyen API directly. Instead route the requests through your own backend. For that, you need an [Adyen account](https://www.adyen.com/signup) and an [API key](https://docs.adyen.com/development-resources/how-to-get-the-api-key).
+
+## Installation
+
+### Add package:
+
+With Flutter:
+```
+$ flutter pub add adyen_checkout
+```
+This will add a line like this to your package's pubspec.yaml (and run an implicit flutter pub get):
+```yaml
+dependencies:
+  adyen_checkout: ^0.0.1
+```
+Alternatively, your editor might support flutter pub get. Check the docs for your editor to learn more.
+
+### Use package
+Now in your Dart code, you can use:
+```dart
+import 'package:adyen_checkout/adyen_checkout.dart';
+```
+<br/>
+
+### Android integration (SDK >= 21)
+
+Adjust your activity to inherit from `FlutterFragmentActivity`: 
+  ```kotlin
+  import io.flutter.embedding.android.FlutterFragmentActivity
+
+  class MainActivity: FlutterFragmentActivity() {
+      // ...
+  }
+  ```
+
+When using the **card component**, it is necessary to declare the intent filter within `AndroidManifest.xml`. 
+  ```xml
+    <intent-filter>
+        <action android:name="android.intent.action.VIEW" />
+        <category android:name="android.intent.category.DEFAULT" />
+        <category android:name="android.intent.category.BROWSABLE" />
+        <data
+            android:host="YOUR_APPLICATION_ID e.g. com.adyen.checkout.flutter.example"
+            android:path="YOUR_CUSTOM_PATH e.g. /card"
+            android:scheme="adyencheckout" />
+    </intent-filter>
+  ```
+<br/>
+
+### iOS integration (SDK >= 12)
+
+Add return URL handler to your `AppDelegate.swift`: 
+
+```swift
+override func application(_: UIApplication, open url: URL, options _: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
+        RedirectComponent.applicationDidOpen(from: url)
+        return true
+}
+```
+Add [custom URL Scheme](https://developer.apple.com/documentation/xcode/defining-a-custom-url-scheme-for-your-app) to your app that matches the return URL. </br>
+When using a voucher payment method in **drop-in**, add a photo library usage description to the `Info.plist` file.  
+
+## Usage
+
+For general understanding of how the prebuilt UI of Adyen (Drop-in or components) work you can follow [our documentation](https://docs.adyen.com/online-payments/prebuilt-ui).
+Adyen offers two ways of proceeding payments within your app. Either through a `session` or through the `advanced` mode. 
+
+### Drop-in session: 
+
+1. Fetch a session from your backend. 
+2. Create the `DropInConfiguration`. 
+3. Request a session by using the package: 
+```dart
+final SessionCheckout sessionCheckout = await AdyenCheckout.session.create(
+    sessionId: sessionResponse.id,
+    sessionData: sessionResponse.sessionData,
+    configuration: dropInConfiguration,
+);
+```
+4. Start the Drop-in UI and wait for the payment result: 
+```dart 
+final PaymentResult paymentResult =  await AdyenCheckout.session.startDropIn(
+    dropInConfiguration: dropInConfiguration,
+    checkout: sessionCheckout,
+);
+```
+5. The payment flow is completed. Continue by handling the payment result. 
+
+
+### Drop-in advanced:
+
+1. Fetch payment methods from you backend. 
+2. Create the `DropInConfiguration`. 
+3. Create an `AdvancedCheckout` object. You must provide two callbacks (`postPayments` and `postPaymentsDetails`) bridging to your backend. These callbacks are being triggered during the payment process. 
+4. Start the Drop-in UI and wait for the payment result: 
+```dart 
+final paymentResult = await AdyenCheckout.advanced.startDropIn(
+    dropInConfiguration: dropInConfiguration,
+    paymentMethodsResponse: paymentMethodsResponse,
+    checkout: advancedCheckout,
+);
+```
+1. The payment flow is completed. Continue by handling the payment result. 
+
+<br>
+
+### Card component session:
+1. Fetch a session from your backend. 
+2. Create the `CardComponentConfiguration`. 
+3. Request a session by using the package: 
+```dart
+final sessionCheckout = await AdyenCheckout.session.create(
+    sessionId: sessionResponse.id,
+    sessionData: sessionResponse.sessionData,
+    configuration: cardComponentConfiguration,
+);
+```
+4. Extract the desired card payment method from the sessionCheckout.
+5. Create card component widget: 
+```dart
+AdyenCardComponent(
+    configuration: cardComponentConfiguration,
+    paymentMethod: paymentMethod,
+    checkout: sessionCheckout,
+    onPaymentResult: (paymentResult) async {
+        // handle paymentResult
+    },
+);
+``` 
+
+### Card component advanced:
+
+1. Fetch payment methods from you backend. 
+2. Extract the desired card payment method from the payment methods list.
+3. Create the `CardComponentConfiguration`. 
+4. Create an `AdvancedCheckout` object. You must provide two callbacks (`postPayments` and `postPaymentsDetails`) bridging to your backend. These callbacks are being triggered during the payment process. 
+5. Create card component widget: 
+```dart
+AdyenCardComponent(
+    configuration: cardComponentConfiguration,
+    paymentMethod: paymentMethod,
+    checkout: advancedCheckout,
+    onPaymentResult: (event) async {
+        // handle paymentResult
+    },
+);
+``` 
+
+
+## Support
+
+If you have a feature request, or spotted a bug or a technical problem, [create an issue here](https://github.com/Adyen/adyen-flutter/issues).
+
+For other questions, [contact our support team](https://www.adyen.help/hc/en-us/requests/new).
+
+## Analytics and data tracking
+
+Drop-in and Components integrations contain analytics and tracking features that are turned on by default. Find out more about [what we track and how you can control it](https://docs.adyen.com/online-payments/analytics-and-data-tracking). Analytics can be disabled by setting `AnalyticsOptions(enabled: false)` within the configuration object.
+
+## Contributing
+
+We merge every pull request into the `develop` branch. We aim to keep `develop` in good shape, which allows us to release a new version whenever we need to.
+
+We strongly encourage you to provide feedback or by contributing to our repository. Find out more in our [contribution guidelines](https://github.com/Adyen/.github/blob/master/CONTRIBUTING.md)
+
+## License
+
+This repository is available under the [MIT license](LICENSE).