The Easiest Implementation of Subscriptions for Flutter

Add the plugin to your Flutter app:

 $ flutter pub add linkfive_purchases

Getting Started

Initialize the SDK. Read our more detailed docs

await LinkFivePurchases.init("LinkFive Api Key");

Get your API key after Sign up. It's free!

Fetch all available subscriptions from LinkFive. The result will be passed to the stream or returned as a Future. Fetch Docs

LinkFivePurchases.fetchProducts();

// or also

LinkFiveProducts? products = await LinkFivePurchases.fetchProducts(); 

Product Streams

LinkFive mainly uses streams to send data to your application. Active Subscriptions Docs

// Stream of subscriptions to offer to the user
LinkFivePurchases.products

// Stream of purchased subscriptions
LinkFivePurchases.activeProducts

// to listen to a stream do the following:
LinkFivePurchases.products.listen((LinkFiveProducts products) {
  print(products);
});

// or for all active Products
LinkFivePurchases.activeProducts.listen((LinkFiveActiveProducts activeProducts) {
  print(activeProducts);
});

Purchase a Subscription

Simply call purchase with the productDetails from the retrieved subscriptions. Purchase Docs

await LinkFivePurchases.purchase( productDetails );

Restore a Purchases

All restored subscriptions will be available through activeProducts. Restore Docs

LinkFivePurchases.restore();

Switch from one subscription plan to another

You can switch from one Subscription plan to another. Example: from currently a 1 month subscription to a 3 months subscription.

  • On iOS: you can only switch to a plan which is in the same Subscription Family

The Proration Mode is Google Only. On default, it replaces immediately the subscription and the remaining time will be prorated and credited to the user. You can specify a different proration mode.

LinkFivePurchases.switchPlan(
  oldPurchaseDetails, 
  linkFiveProductDetails.productDetails,
  prorationMode: ProrationMode.immediateWithTimeProration
);

Provider usage

We offer a Provider Plugin which you can implement and use out of the box or you can create your own provider.

LinkFive Provider Package

Check out linkfive_purchases_provider

You just have to register the Provider with our API key and you're all set to use it

MultiProvider(
  providers: [
    // ...
    ChangeNotifierProvider(
      create: (context) => LinkFiveProvider("API_KEY"),
      lazy: false,
    ),
  ]
)

Provider example

class LinkFiveProvider extends ChangeNotifier {
  LinkFivePurchasesMain linkFivePurchases = LinkFivePurchasesMain();

  LinkFiveProducts? products;
  LinkFiveActiveProducts? activeProducts;

  List<StreamSubscription> _streams = [];

  LinkFiveProvider() {
    linkFivePurchases.init("keys.linkFiveApiKey");
    linkFivePurchases.fetchProducts();
    _streams.add(linkFivePurchases.products.listen(_productsUpdate));
    _streams.add(linkFivePurchases.activeProducts.listen(_activeProductsUpdate));
  }

  void _productsUpdate(LinkFiveProducts data) async {
    products = data;
    notifyListeners();
  }

  void _activeProductsUpdate(LinkFiveActiveProducts data) {
    activeProducts = data;
    notifyListeners();
  }

  Future<LinkFiveProducts?> fetchProducts() {
    return LinkFivePurchases.fetchProducts();
  }

  restoreSubscriptions() {
    return LinkFivePurchases.restore();
  }

  Future<bool> purchase(ProductDetails productDetail) async {
    return LinkFivePurchases.purchase(productDetail);
  }

  switchPlan(LinkFivePlan oldPurchasePlan, LinkFiveProductDetails productDetails,
      {ProrationMode? prorationMode}) {
    return LinkFivePurchases.switchPlan(oldPurchasePlan, productDetails,
        prorationMode: prorationMode);
  }

  @override
  void dispose() {
    _streams.forEach((element) async {
      await element.cancel();
    });
    _streams = [];
    super.dispose();
  }
}

StreamBuilder Example

If you're mainly using a StreamBuilder. You can implement LinkFive in the following way:

Show all available Products:

StreamBuilder<LinkFiveProducts>(
  stream: LinkFivePurchases.products,
  builder: (context, snapshot) {
    if (snapshot.hasData) {
     var productData = snapshot.data;
      if(productData != null) {
      // productData to offer
     }
    }
  return Center(child: Text('Loading...'));
  })

Get all Active products

StreamBuilder<LinkFiveActiveProducts>(
  stream: LinkFivePurchases.activeProducts,
  builder: (BuildContext context, snapshot) {
    if (snapshot.hasData) {
      var activeProductsData = snapshot.data;
      if (activeProductsData != null) {
        // activeProductsData to offer
      }
    }
    return Center(child: Text('Loading...'));
  },
)

Easy Integration with the Paywall UI package

Integrate linkfive_purchases with package in_app_purchases_paywall_ui.

  • it's working with just passing the LinkFive client to the UI library
  • Automatic purchase state management
  • The UI is fully customizable
  • You can control the UI on our Website

Purchase Page

Simple Paywall

Success Page

Simple Success page Paywall

Page State Management

Simple Paywall Success state

Example usage with Paywall UI

usage with in_app_purchases_paywall_ui.


// get subscription data from your provider or from your stream (as described above)
LinkFiveProducts? products = // your products you got through the products Stream

SimplePaywall(
  // ...
  // basically just the linkFivePurchases class
  callbackInterface: LinkFivePurchases.callbackInterface,

  // you can use your own strings or use the intl package to automatically generate the subscription strings
  subscriptionListData: products?.paywallUIHelperData(context: context) ?? [],
  // ...
);

That‘s it. Now the page will automatically offer the subscriptions to the user or if the user already bought the subscription, the paywall will show the success page.

Libraries

default_purchase_handler
initialize_extension
linkfive_active_products
linkfive_app_data_store
linkfive_billing_client
linkfive_billing_client_interface
linkfive_billing_client_test
linkfive_client
linkfive_client_interface
linkfive_client_test
linkfive_plan
linkfive_prefs
linkfive_products
linkfive_purchases
linkfive_purchases
LinkFive Purchases Package
linkfive_purchases_main
linkfive_response
linkfive_restore_apple_item
linkfive_restore_google_item
linkfive_store
linkfive_user_management
linkfive_verified_receipt
subscription_duration_convert
upgrade_downgrade_purchases