Draft: add support for adding a LaunchActivity to Android expo apps

package.json

@@ -71,7 +71,7 @@
     "react-native-webview": "^13.16.0"
   },
   "devDependencies": {
-    "@expo/config-plugins": "^9.0.16",
+    "@expo/config-plugins": "^54.0.3",
     "@react-native/babel-preset": "^0.81.0",
     "@react-native/eslint-config": "^0.81.1",
     "@types/jest": "^29.5.14",

src/plugin/with-android-launch-activity/LaunchActivity.kt.template

@@ -0,0 +1,23 @@
+package {{package}}
+import {{package}}.MainApplication
+
+import android.app.Activity
+import android.content.Intent
+import android.os.Bundle
+
+class LaunchActivity : Activity() {
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        val application = application as MainApplication
+
+        // check that MainActivity is not started yet
+        if (!application.isActivityInBackStack(MainActivity::class.java)) {
+            val intent = Intent(this, MainActivity::class.java)
+            startActivity(intent)
+        }
+
+        finish()
+    }
+}

src/plugin/with-android-launch-activity/withAndroidLaunchActivity.ts

@@ -0,0 +1,186 @@
+import {
+  AndroidConfig,
+  ConfigPlugin,
+  withAndroidManifest,
+  withDangerousMod,
+  withMainActivity,
+  withMainApplication,
+  CodeGenerator,
+} from '@expo/config-plugins';
+import fs from 'node:fs';
+import path from 'node:path';
+
+const LAUNCH_ACTIVITY_TEMPLATE = fs.readFileSync(
+  path.join(__dirname, 'LaunchActivity.kt.template'),
+  'utf-8'
+);
+
+export const withAndroidLaunchActivity: ConfigPlugin<{
+  addLaunchActivity?: boolean;
+}> = (expoConfig, { addLaunchActivity = false }) => {
+  if (!addLaunchActivity) return expoConfig;
+  const androidPackage = expoConfig.android?.package;
+  if (!androidPackage) return expoConfig;
+
+  let resultConfig = withDangerousMod(expoConfig, [
+    'android',
+    async (config) => {
+      const appSrcDir = path.join(
+        config.modRequest.platformProjectRoot,
+        'app/src/main/java/',
+        ...config.android!.package!.split('.')
+      );
+      const filePath = path.join(appSrcDir, 'LaunchActivity.kt');
+      fs.mkdirSync(appSrcDir, { recursive: true });
+      const fileContent = LAUNCH_ACTIVITY_TEMPLATE.replace(
+        /{{package}}/g,
+        config.android!.package!
+      );
+      fs.writeFileSync(filePath, fileContent);
+      return config;
+    },
+  ]);
+
+  resultConfig = withAndroidManifest(resultConfig, (config) => {
+    const mainApplication = config?.modResults?.manifest?.application?.[0];
+
+    if (!mainApplication) throw new Error('MainApplication missing!');
+    if (!mainApplication.activity)
+      throw new Error('MainApplication has no activities!');
+
+    const mainActivityIndex = mainApplication.activity?.findIndex(
+      (activity) => activity.$['android:name'] === '.MainActivity'
+    );
+    if (mainActivityIndex === -1) throw new Error('Missing MainActivity!');
+
+    const mainActivity = mainApplication.activity[mainActivityIndex];
+    removeIntentFilter(mainActivity, 'android.intent.category.LAUNCHER');
+    ensureLaunchActivity(mainApplication);
+
+    return config;
+  });
+
+  resultConfig = withMainApplication(resultConfig, (config) => {
+    const { modResults } = config;
+
+    if (
+      config.modResults.contents.includes(
+        '@generated begin @stripe/stripe-react-native'
+      )
+    )
+      return config;
+
+    const merged = CodeGenerator.mergeContents({
+      src: modResults.contents,
+      comment: '  //',
+      tag: '@stripe/stripe-react-native',
+      offset: 0,
+      anchor: / {2}override val reactNativeHost:/,
+      newSrc: `  private val runningActivities = ArrayList<Class<*>>()
+
+  fun addActivityToStack(cls: Class<*>) {
+      if (!runningActivities.contains(cls)) {
+          runningActivities.add(cls)
+      }
+  }
+
+  fun removeActivityFromStack(cls: Class<*>) {
+      runningActivities.remove(cls)
+  }
+
+  fun isActivityInBackStack(cls: Class<*>): Boolean {
+      return runningActivities.contains(cls)
+  }`,
+    });
+    config.modResults.contents = merged.contents;
+
+    return config;
+  });
+
+  resultConfig = withMainActivity(resultConfig, (config) => {
+    if (
+      config.modResults.contents.includes(
+        '@generated begin @stripe/stripe-react-native'
+      )
+    )
+      return config;
+    const { modResults } = config;
+    const { language } = modResults;
+
+    if (
+      config.modResults.contents.includes(
+        '@generated begin @stripe/stripe-react-native'
+      )
+    )
+      return config;
+
+    const withImports = AndroidConfig.CodeMod.addImports(
+      modResults.contents,
+      [`${androidPackage}.MainApplication`],
+      language === 'java'
+    );
+
+    const merged = CodeGenerator.mergeContents({
+      src: withImports,
+      comment: '    //',
+      tag: '@stripe/stripe-react-native',
+      offset: 1,
+      anchor: /super\.onCreate\(null\)/,
+      newSrc: `\
+    val app = application as MainApplication
+    app.addActivityToStack(this::class.java)
+  }
+
+  override fun onDestroy() {
+    super.onDestroy()
+    val app = application as MainApplication
+    app.removeActivityFromStack(this::class.java)
+`,
+    });
+
+    config.modResults.contents = merged.contents;
+    return config;
+  });
+
+  return resultConfig;
+};
+
+/** Removes all intent-filters with an action matching the specified name */
+function removeIntentFilter(
+  activity: AndroidConfig.Manifest.ManifestActivity,
+  intentFilterCategoryName: string
+) {
+  if (!activity['intent-filter']) return;
+  activity['intent-filter'] = activity['intent-filter'].filter(
+    (filter) =>
+      !filter.category?.find(
+        (category) => category.$['android:name'] === intentFilterCategoryName
+      )
+  );
+}
+
+function ensureLaunchActivity(
+  application: AndroidConfig.Manifest.ManifestApplication
+) {
+  application.activity ??= [];
+  const activities = application.activity;
+  const hasLaunchActivity = activities.some(
+    (activity) => activity.$['android:name'] === '.LaunchActivity'
+  );
+  if (hasLaunchActivity) return;
+
+  activities.push({
+    '$': {
+      'android:exported': 'true',
+      'android:name': '.LaunchActivity',
+    },
+    'intent-filter': [
+      {
+        action: [{ $: { 'android:name': 'android.intent.action.MAIN' } }],
+        category: [
+          { $: { 'android:name': 'android.intent.category.LAUNCHER' } },
+        ],
+      },
+    ],
+  });
+}

src/plugin/withStripe.ts

@@ -9,6 +9,7 @@ import {
   withPodfile,
 } from '@expo/config-plugins';
 import path from 'path';
+import { withAndroidLaunchActivity } from './with-android-launch-activity/withAndroidLaunchActivity';
 
 const {
   addMetaDataItemToMainApplication,
@@ -32,12 +33,23 @@ type StripePluginProps = {
    * Defaults to false.
    */
   includeOnramp?: boolean;
+  /**
+   * If true, an extra activity will be added to the AndroidManifest.xml,
+   * to support re-opening your app during ongoing/finished 3DS2 verification.
+   * See [docs/android-chrome-tab-closes-on-background.md](docs/android-chrome-tab-closes-on-background.md)
+   * for more details.
+   *
+   *
+   * Defaults to false.
+   */
+  addLaunchActivity?: boolean;
 };
 
 const withStripe: ConfigPlugin<StripePluginProps> = (config, props) => {
   config = withStripeIos(config, props);
   config = withNoopSwiftFile(config);
   config = withStripeAndroid(config, props);
+  config = withAndroidLaunchActivity(config, props);
   return config;
 };