Flutter SDK 8.x to 9.x migration guide

We've upgraded the Google Play Billing Library dependency for Android to version 7 in this release, leading to several changes in our SDK. These are described below.

Upgrading version

Increase the dependency version in your prodspec.yaml file to upgrade your Qonversion SDK to the latest

dependencies:
  qonversion_flutter: ^8.0.0

Android deployment upgrades

With the new Google Play Billing Library 7 we've increased our minSdkVersion to 21 and targetSdkVersion to 34 for Android.

If you were using lower minSdkVersion you should upgrade it to 21 to use the latest version of our SDK and Google Play Billing Library. If you have already targeted the 21+ version, you should do nothing.

Installment plans support

In the latest library version, Google introduces installment plans, when a customer commits to pay for several subsequent subscription periods. In our release, we've added a new field installmentPlanDetails to QProductOfferDetails with the details of the installment plan if they exist. It contains the following information:

We've also added an isInstallment flag to QProductStoreDetails to check if the current product has an installment plan or not.

Below is an example of those fields usage:

var products = await Qonversion.getSharedInstance().products();
var installmentProduct = products["installmentProductId"];
var storeDetails = installmentProduct?.storeDetails;
if (storeDetails?.isInstallment == true) {
  var installmentPlanDetails = storeDetails?.basePlanSubscriptionOfferDetails?.installmentPlanDetails;
  // Use the installment plan information
}

Fallback files

We're happy to introduce the fallback files support in this release to make our system reliability even higher. Fallback files allow your app to work as expected in rare cases of network connection or Qonversion API issues for new users without a cache available. This allows purchases and entitlements to be processed for new users even if the Qonversion API faces issues. This also makes it possible to receive remote configs for cases when the network connection is unavailable.

Fallback files are available both on iOS and Android.

Read more about the fallback files in the documentation.

Error codes

In this release, we have added the QErrorCode enum with the list of defined Qonversion error codes. Now you can compare any error code with the defined one to check any specific case as follows:

try {
  await Qonversion.getSharedInstance().purchase(...);
} catch (e) {
  if (e.code == QErrorCode.storeProductNotAvailable) {
    // The requested product is unavailable for purchase.
  }
}

We've also changed the type of QError.code field from String to QErrorCode.

The other changes

• Pending purchases support was added for prepaid subscriptions on Android.
• QEligibilityStatus nonIntroProduct was renamed to nonIntroOrTrialProduct to better reflect the meaning.