Refactor example app UI and improve context handling

Redesigned the example app with new Section, Field, and ToggleRow components for a more organized and modern UI, updated styles for a light theme, and improved the display of security capabilities and stored items. On Android, ReactContextHolder now tracks FragmentActivity more robustly and manages lifecycle listeners to ensure correct activity references for biometric prompts. Removed unnecessary FragmentActivity check in BiometricAuthenticator.

Author: mCodex

android/src/main/java/com/sensitiveinfo/internal/auth/BiometricAuthenticator.kt

@@ -172,9 +172,6 @@ internal class BiometricAuthenticator {
   private fun currentFragmentActivity(): FragmentActivity {
     val activity = ReactContextHolder.currentActivity()
       ?: throw IllegalStateException("Unable to show authentication prompt: no active React activity.")
-    if (activity !is FragmentActivity) {
-      throw IllegalStateException("Current activity does not support FragmentManager required for biometric prompts.")
-    }
     return activity
   }
 

android/src/main/java/com/sensitiveinfo/internal/util/ReactContextHolder.kt

@@ -2,6 +2,8 @@ package com.sensitiveinfo.internal.util
 
 import android.app.Activity
 import com.facebook.react.bridge.ReactApplicationContext
+import com.facebook.react.bridge.LifecycleEventListener
+import androidx.fragment.app.FragmentActivity
 import java.lang.ref.WeakReference
 import java.util.concurrent.atomic.AtomicReference
 
@@ -16,23 +18,59 @@ import java.util.concurrent.atomic.AtomicReference
 internal object ReactContextHolder {
   // Keep only a weak reference so the React instance can be GC'd after teardown.
   private val contextRef = AtomicReference<WeakReference<ReactApplicationContext>?>(null)
+  private val activityRef = AtomicReference<WeakReference<FragmentActivity>?>(null)
+  private val lifecycleListener = object : LifecycleEventListener {
+    override fun onHostResume() {
+      captureActivity(contextRef.get()?.get()?.currentActivity)
+    }
+
+    override fun onHostPause() {
+      // No-op. We keep the last resumed activity to support prompts during pauses triggered by UI overlays.
+    }
+
+    override fun onHostDestroy() {
+      clearActivity()
+    }
+  }
 
   fun install(context: ReactApplicationContext) {
     val current = contextRef.get()?.get()
     if (current === context) {
       return
     }
+    current?.removeLifecycleEventListener(lifecycleListener)
+    context.addLifecycleEventListener(lifecycleListener)
     contextRef.set(WeakReference(context))
+    captureActivity(context.currentActivity)
   }
 
   fun clear() {
-    contextRef.set(null)
+    contextRef.getAndSet(null)?.get()?.removeLifecycleEventListener(lifecycleListener)
+    clearActivity()
   }
 
   fun requireContext(): ReactApplicationContext {
     return contextRef.get()?.get()
       ?: throw IllegalStateException("ReactApplicationContext not yet available for SensitiveInfo.")
   }
 
-  fun currentActivity(): Activity? = contextRef.get()?.get()?.currentActivity
+  fun currentActivity(): FragmentActivity? {
+    val active = activityRef.get()?.get()
+    if (active != null && !active.isFinishing && !active.isDestroyed) {
+      return active
+    }
+
+    val contextActivity = contextRef.get()?.get()?.currentActivity as? FragmentActivity
+    captureActivity(contextActivity)
+    return contextActivity
+  }
+
+  private fun captureActivity(activity: Activity?) {
+    val fragmentActivity = activity as? FragmentActivity ?: return
+    activityRef.set(WeakReference(fragmentActivity))
+  }
+
+  private fun clearActivity() {
+    activityRef.getAndSet(null)?.clear()
+  }
 }