[webview_flutter] Add support for payment requests on Android #9679

mataku · 2025-07-26T12:55:40Z

Expose android native WebViewFeature#isFeatureSupported, WebSettingsCompat#setPaymentRequestEnabled and WebViewFeature#PAYMENT_REQUEST to allow developers to check if payment request feature is supported in WebView.

This change is for Google Pay integration in Android WebView.
Fixes flutter/flutter#172150

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Code Review

This PR adds support for checking and enabling the Payment Request API on Android. The changes look good overall, with new APIs on AndroidWebViewController and corresponding native implementations and tests. I've left a few comments to improve documentation, example code clarity, and changelog formatting to better align with the project's standards. Once these are addressed, this should be ready to merge.

gemini-code-assist · 2025-07-26T12:57:19Z

packages/webview_flutter/webview_flutter_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 4.9.0
+
+* Adds support to check payment request is supported.


This changelog entry could be more descriptive and follow the repository's style guide more closely (e.g., complete sentence, ending with a period, using code formatting for API names).

Suggested change

* Adds support to check payment request is supported.

* Adds support for the Payment Request API with `AndroidWebViewController.isWebViewFeatureSupported` and `AndroidWebViewController.setPaymentRequestEnabled`.

gemini-code-assist · 2025-07-26T12:57:19Z

packages/webview_flutter/webview_flutter_android/example/lib/main.dart

+    final bool paymentRequestEnabled = await androidController
+        .isWebViewFeatureSupported(WebViewFeatureType.paymentRequest);
+
+    // Call this method to enable the Payment Request API.
+    // if (paymentRequestEnabled) {
+    //   await androidController.setPaymentRequestEnabled(true);
+    // }
+
+    if (context.mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+        content: Text('Payment Request API enabled: $paymentRequestEnabled'),
+      ));


The variable name paymentRequestEnabled is a bit misleading as it stores the result of isWebViewFeatureSupported. A name like isPaymentRequestSupported would be clearer. Similarly, the snackbar message says 'enabled' but it's showing whether the feature is 'supported'. This could be confusing for developers looking at the example.

final bool isPaymentRequestSupported = await androidController .isWebViewFeatureSupported(WebViewFeatureType.paymentRequest); // Call this method to enable the Payment Request API. // if (isPaymentRequestSupported) { // await androidController.setPaymentRequestEnabled(true); // } if (context.mounted) { ScaffoldMessenger.of(context).showSnackBar(SnackBar( content: Text('Payment Request API supported: $isPaymentRequestSupported'), ));

gemini-code-assist · 2025-07-26T12:57:19Z

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

@@ -909,6 +938,12 @@ enum MixedContentMode {
  neverAllow,
 }

+/// See https://developer.android.com/reference/androidx/webkit/WebViewFeature#constants_1.
+enum WebViewFeatureType {
+  /// Feature for isFeatureSupported. This feature covers setPaymentRequestEnabled, getPaymentRequestEnabled, setHasEnrolledInstrumentEnabled, and getHasEnrolledInstrumentEnabled,


This comment is very long and could be wrapped to adhere to the 80-character line limit. Also, it mentions methods like getPaymentRequestEnabled which are not exposed in this PR, which could be confusing. Consider rephrasing to be more concise and accurate to what is currently exposed, for example, by linking to the setPaymentRequestEnabled method.

/// This feature covers [setPaymentRequestEnabled].

…led if the feature PAYMENT_REQUEST is present Ensures the function works correctly even when called without prior WebViewFeature.isFeatureSupported check. ref. https://developers.google.com/pay/api/android/guides/recipes/using-android-webview#enable-payment-request-api

bparrishMines

Thanks for the contribution! This looks good, just a handful of comments about documentation.

bparrishMines · 2025-07-31T19:35:31Z

...droid/android/src/main/java/io/flutter/plugins/webviewflutter/WebSettingsCompatProxyApi.java

+/**
+ * Host api implementation for {@link WebSettingsCompat}.
+ *
+ * <p>Handles static methods for {@link WebSettingsCompat}.
+ */


It looks like this was copied from the other api implementations which are actually incorrect. You can change this to:

Suggested change

/**

* Host api implementation for {@link WebSettingsCompat}.

*

* <p>Handles static methods for {@link WebSettingsCompat}.

*/

/**

* Proxy API implementation for {@link WebSettingsCompat}.

*

* <p>This class may handle instantiating and adding native object instances that are attached to a

* Dart instance or handle method calls on the associated native class or an instance of the class.

*/

bparrishMines · 2025-07-31T19:36:12Z

..._android/android/src/main/java/io/flutter/plugins/webviewflutter/WebViewFeatureProxyApi.java

+/**
+ * Host api implementation for {@link WebViewFeature}.
+ *
+ * <p>Handles creating {@link WebViewFeature}s that intercommunicate with a paired Dart object.
+ */


Same for here:

Suggested change

/**

* Host api implementation for {@link WebViewFeature}.

*

* <p>Handles creating {@link WebViewFeature}s that intercommunicate with a paired Dart object.

*/

/**

* Proxy API implementation for {@link WebViewFeature}.

*

* <p>This class may handle instantiating and adding native object instances that are attached to a

* Dart instance or handle method calls on the associated native class or an instance of the class.

*/

bparrishMines · 2025-07-31T19:47:20Z

packages/webview_flutter/webview_flutter_android/example/lib/main.dart

nit: I don't think we need to update the example app, because there is nothing to print or display to verify it is actually working. This just checks that the method is called, but this is already covered by unit tests.

I agree. removed in 3f68c0e

bparrishMines · 2025-07-31T19:52:36Z

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

+  ///
+  /// Before calling this method, you should check if the feature is supported using
+  /// [isWebViewFeatureSupported] with [WebViewFeatureConstants.paymentRequest].
+  Future<void> setPaymentRequestEnabled(bool enabled) {


The docs show that the manifest also needs to be updated: https://developer.android.com/reference/androidx/webkit/WebSettingsCompat#setPaymentRequestEnabled(android.webkit.WebSettings,boolean)

I would also include the manifest update in the docs here.

Thank you for the feedback! I've also added the content of the AndroidManifest update: 28f8889

bparrishMines · 2025-07-31T19:52:54Z

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

@@ -909,6 +938,12 @@ enum MixedContentMode {
  neverAllow,
 }

+/// See https://developer.android.com/reference/androidx/webkit/WebViewFeature#constants_1.
+enum WebViewFeatureType {
+  /// Feature for isFeatureSupported. This feature covers [WebSettingsCompat.setPaymentRequestEnabled].


nit: Space after first sentence.

Suggested change

/// Feature for isFeatureSupported. This feature covers [WebSettingsCompat.setPaymentRequestEnabled].

/// Feature for isFeatureSupported.

///

/// This feature covers [WebSettingsCompat.setPaymentRequestEnabled].

bparrishMines · 2025-07-31T19:56:56Z

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

@@ -909,6 +938,12 @@ enum MixedContentMode {
  neverAllow,
 }

+/// See https://developer.android.com/reference/androidx/webkit/WebViewFeature#constants_1.


I would include a description like:

Suggested change

/// See https://developer.android.com/reference/androidx/webkit/WebViewFeature#constants_1.

/// WebView support library feature types used to query for support on the device.

///

/// See https://developer.android.com/reference/androidx/webkit/WebViewFeature#constants_1.

bparrishMines · 2025-07-31T19:59:49Z

packages/webview_flutter/webview_flutter_android/pigeons/android_webkit.dart

+@ProxyApi(
+  kotlinOptions: KotlinProxyApiOptions(
+    fullClassName: 'androidx.webkit.WebSettingsCompat',
+  ),
+)
+abstract class WebSettingsCompat {


This also needs docs like the other proxyapis. A one-liner and a link is usually fine:

/// Compatibility version of `WebSettings`. /// /// See https://developer.android.com/reference/kotlin/androidx/webkit/WebSettingsCompat

bparrishMines · 2025-07-31T19:59:59Z

packages/webview_flutter/webview_flutter_android/pigeons/android_webkit.dart

+    fullClassName: 'androidx.webkit.WebViewFeature',
+  ),
+)
+abstract class WebViewFeature {


Same for here

method doc is enough

bparrishMines

LGTM with a couple more comments on docs.

@stuartmorgan-g This is ready for a secondary review.

bparrishMines · 2025-08-01T15:57:12Z

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

+  /// This method uses [android_webview.WebViewFeature.isFeatureSupported] to check
+  /// if the specified WebView feature is available on the current device and WebView version.
+  ///
+  /// See [WebViewFeatureConstants] for available feature constants.


I think you meant to use type here since it is apart of the exported api.

Suggested change

/// See [WebViewFeatureConstants] for available feature constants.

/// See [WebViewFeatureType] for available feature constants.

bparrishMines · 2025-08-01T15:57:28Z

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_controller.dart

+  /// to enable or disable the Payment Request API for the WebView.
+  ///
+  /// Before calling this method, you should check if the feature is supported using
+  /// [isWebViewFeatureSupported] with [WebViewFeatureConstants.paymentRequest].


Same here

Suggested change

/// [isWebViewFeatureSupported] with [WebViewFeatureConstants.paymentRequest].

/// [isWebViewFeatureSupported] with [WebViewFeatureType.paymentRequest].

stuartmorgan-g

This should get a short section in the package's README describing it; platform-specific extensions are non-obvious, so we should highlight them in the README in general.

stuartmorgan-g · 2025-08-05T19:35:58Z

...droid/android/src/main/java/io/flutter/plugins/webviewflutter/WebSettingsCompatProxyApi.java

+
+  @Override
+  public void setPaymentRequestEnabled(@NonNull WebSettings webSettings, boolean enabled) {
+    if (WebViewFeature.isFeatureSupported(WebViewFeature.PAYMENT_REQUEST)) {


Why is this check being done internally on the native side, rather than being a straight pass-through? I would expect this to work the same way the SDK works, which is that clients are responsible for this.

@stuartmorgan-g This was to address Android lint's RequiresFeature, but as you pointed out, since it's natural to use it after checking WebViewFeature.isFeatureSupported, it was indeed excessive checking. Therefore, I will address it with SuppressLint.

mataku added 7 commits July 26, 2025 18:42

Add wrapper for androidx.webkit.WebSettingsCompat

2d07746

Add wrapper for androidx.webkit.WebViewFeature

1a01f13

Expose wrappers

d098b47

Add native unit tests for payment request feature

8fa5fe1

Add sample menu for payment request

381ae6f

Prepare CHANGELOG

5eee7b3

Run auto-formatter

d43bde1

github-actions bot added platform-android p: webview_flutter labels Jul 26, 2025

gemini-code-assist bot reviewed Jul 26, 2025

View reviewed changes

mataku added 2 commits July 26, 2025 22:00

Simplify method description

a20f0fb

Specify details with added methods

103e29f

mataku changed the title ~~[webview_flutter_android] Add support to check payment request is supported~~ [webview_flutter_android] Add support to check whether payment request is supported in WebView Jul 26, 2025

mataku force-pushed the feature/expose-payment-request-enabled branch from f79ef2c to 8c73517 Compare July 26, 2025 14:24

Fix format

5ed43ab

mataku marked this pull request as ready for review July 26, 2025 15:00

mataku requested a review from bparrishMines as a code owner July 26, 2025 15:00

bparrishMines requested changes Jul 31, 2025

View reviewed changes

mataku added 3 commits August 1, 2025 14:56

Fix doc comments to correspond to the method

28f8889

Remove sample for WebSettingsCompat and WebViewFeature.

3f68c0e

method doc is enough

Update generated files according to comment update

878fd38

mataku requested a review from bparrishMines August 1, 2025 06:46

bparrishMines approved these changes Aug 1, 2025

View reviewed changes

mataku added 2 commits August 2, 2025 14:37

Specify collect type

b0388bc

Merge main into feature/expose-payment-request-enabled

5f7f689

stuartmorgan-g changed the title ~~[webview_flutter_android] Add support to check whether payment request is supported in WebView~~ [webview_flutter] Add support for payment requests on Android Aug 5, 2025

stuartmorgan-g requested changes Aug 5, 2025

View reviewed changes

		@@ -1,3 +1,7 @@
		## 4.9.0

		* Adds support to check payment request is supported.

	* Adds support to check payment request is supported.
	* Adds support for the Payment Request API with `AndroidWebViewController.isWebViewFeatureSupported` and `AndroidWebViewController.setPaymentRequestEnabled`.

-/**
- * Host api implementation for {@link WebSettingsCompat}.
- *
- * <p>Handles static methods for {@link WebSettingsCompat}.
- */
+/**
+ * Proxy API implementation for {@link WebSettingsCompat}.
+ *
+ * <p>This class may handle instantiating and adding native object instances that are attached to a
+ * Dart instance or handle method calls on the associated native class or an instance of the class.
+ */

	/// See [WebViewFeatureConstants] for available feature constants.
	/// See [WebViewFeatureType] for available feature constants.

	/// [isWebViewFeatureSupported] with [WebViewFeatureConstants.paymentRequest].
	/// [isWebViewFeatureSupported] with [WebViewFeatureType.paymentRequest].

[webview_flutter] Add support for payment requests on Android #9679

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mataku commented Jul 26, 2025 •

edited by stuartmorgan-g

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