fix pip feature

apps/weblibre/android/app/src/main/kotlin/eu/weblibre/gecko/MainActivity.kt

@@ -20,8 +20,10 @@
 package eu.weblibre.gecko
 
 import android.content.Context
+import android.content.Intent
 import android.os.Bundle
 import android.util.Log
+import eu.weblibre.flutter_mozilla_components.HomePressDispatcher
 import io.flutter.embedding.android.FlutterFragmentActivity
 import io.flutter.embedding.engine.FlutterEngine
 import io.flutter.embedding.engine.FlutterEngineCache
@@ -29,9 +31,12 @@ import io.flutter.embedding.engine.FlutterJNI
 import io.flutter.embedding.engine.dart.DartExecutor
 import io.flutter.plugin.common.MethodChannel
 
-class MainActivity: FlutterFragmentActivity() {
+class MainActivity : FlutterFragmentActivity() {
     companion object {
         private const val TAG = "MainActivity"
+
+        /** Marks the intent [checkAndExitPiP] sends to itself. */
+        private const val EXTRA_EXIT_PIP = "eu.weblibre.gecko.EXIT_PIP"
     }
 
     private val TRIM_MEMORY_CHANNEL = "eu.weblibre.flutter_mozilla_components/trim_memory"
@@ -48,6 +53,45 @@ class MainActivity: FlutterFragmentActivity() {
             "cachedEngine=${engineTag(FlutterEngineCache.getInstance().get(ENGINE_ID))}")
 
         super.onCreate(null)
+
+        // Restored straight into a pinned task (e.g. the process was killed while in PiP).
+        checkAndExitPiP()
+    }
+
+    override fun onNewIntent(intent: Intent) {
+        if (intent.hasExtra(EXTRA_EXIT_PIP)) {
+            // Our own intent from checkAndExitPiP, delivered back here because
+            // FLAG_ACTIVITY_REORDER_TO_FRONT re-delivers to a singleTask activity. It carries
+            // nothing for Flutter to handle, and acting on it again would recurse.
+            return
+        }
+
+        super.onNewIntent(intent)
+
+        checkAndExitPiP()
+    }
+
+    /**
+     * A picture-in-picture window cannot show a newly opened page, so an intent arriving
+     * while we are in PiP has to pull the task back to the foreground first.
+     */
+    private fun checkAndExitPiP() {
+        if (isInPictureInPictureMode) {
+            moveTaskToBack(false)
+            startActivity(
+                Intent(this, MainActivity::class.java)
+                    .setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT)
+                    .putExtra(EXTRA_EXIT_PIP, true)
+            )
+        }
+    }
+
+    override fun onUserLeaveHint() {
+        if (HomePressDispatcher.onUserLeaveHint(this)) {
+            return
+        }
+
+        super.onUserLeaveHint()
     }
 
     /**

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/BaseBrowserFragment.kt

@@ -25,19 +25,25 @@ import androidx.core.content.edit
 import androidx.fragment.app.Fragment
 import androidx.preference.PreferenceManager
 import eu.weblibre.flutter_mozilla_components.addons.WebExtensionPromptFeature
+import eu.weblibre.flutter_mozilla_components.activities.ExternalAppBrowserActivity
 import eu.weblibre.flutter_mozilla_components.databinding.FragmentBrowserBinding
 import eu.weblibre.flutter_mozilla_components.ext.EventSequence
 import eu.weblibre.flutter_mozilla_components.ext.getPreferenceKey
 import eu.weblibre.flutter_mozilla_components.ext.toPigeonDownloadState
 import eu.weblibre.flutter_mozilla_components.feature.BrowserHandlingScrollFeature
+import eu.weblibre.flutter_mozilla_components.feature.GestureAwareSwipeRefreshFeature
 import eu.weblibre.flutter_mozilla_components.feature.KeyboardVisibilityFeature
 import eu.weblibre.flutter_mozilla_components.feature.ReadabilityExtractFeature
 import eu.weblibre.flutter_mozilla_components.feature.WebExtensionToolbarFeature
 import eu.weblibre.flutter_mozilla_components.integration.ReaderViewIntegration
-import eu.weblibre.flutter_mozilla_components.activities.ExternalAppBrowserActivity
 import eu.weblibre.flutter_mozilla_components.services.DownloadService
 import io.flutter.Log
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.distinctUntilChangedBy
+import kotlinx.coroutines.flow.mapNotNull
 import mozilla.components.browser.state.selector.findCustomTabOrSelectedTab
+import mozilla.components.browser.state.selector.findTabOrCustomTabOrSelectedTab
+import mozilla.components.browser.state.state.SessionState
 import mozilla.components.browser.state.state.WebExtensionState
 import mozilla.components.browser.thumbnails.BrowserThumbnails
 import mozilla.components.concept.engine.EngineView
@@ -55,12 +61,12 @@ import mozilla.components.feature.prompts.file.AndroidPhotoPicker
 import mozilla.components.feature.session.FullScreenFeature
 import mozilla.components.feature.session.PictureInPictureFeature
 import mozilla.components.feature.session.SessionFeature
-import eu.weblibre.flutter_mozilla_components.feature.GestureAwareSwipeRefreshFeature
 import mozilla.components.feature.sitepermissions.SitePermissionsFeature
 import mozilla.components.feature.sitepermissions.SitePermissionsRules
 import mozilla.components.feature.sitepermissions.SitePermissionsRules.AutoplayAction
 import mozilla.components.feature.tabs.WindowFeature
 import mozilla.components.feature.webauthn.WebAuthnFeature
+import mozilla.components.lib.state.ext.flowScoped
 import mozilla.components.support.base.feature.ActivityResultHandler
 import mozilla.components.support.base.feature.PermissionsFeature
 import mozilla.components.support.base.feature.UserInteractionHandler
@@ -471,6 +477,12 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Activit
                 view = binding.root,
             )
 
+            components.core.store.flowScoped(viewLifecycleOwner, Dispatchers.Main) { flow ->
+                flow.mapNotNull { state -> state.findTabOrCustomTabOrSelectedTab(sessionId) }
+                    .distinctUntilChangedBy { tab -> tab.content.pictureInPictureEnabled }
+                    .collect { tab -> pipModeChanged(tab) }
+            }
+
             mediaSessionFullscreenFeature.set(
                 feature = MediaSessionFullscreenFeature(
                     requireActivity(),
@@ -644,8 +656,12 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Activit
 
     override fun onPictureInPictureModeChanged(enabled: Boolean) {
         pictureInPictureFeature?.onPictureInPictureModeChanged(enabled)
-        if (lifecycle.currentState == androidx.lifecycle.Lifecycle.State.CREATED) {
+    }
+
+    private fun pipModeChanged(session: SessionState) {
+        if (!session.content.pictureInPictureEnabled && session.content.fullScreen && isAdded) {
             onBackPressed()
+            fullScreenChanged(false)
         }
     }
 
@@ -691,6 +707,17 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Activit
         keyboardVisibilityFeature?.checkKeyboardState()
     }
 
+    @CallSuper
+    override fun onStop() {
+        super.onStop()
+
+        components.core.store.state.findTabOrCustomTabOrSelectedTab(sessionId)?.let { session ->
+            if (!session.content.pictureInPictureEnabled && fullScreenFeature.onBackPressed()) {
+                fullScreenChanged(false)
+            }
+        }
+    }
+
     override fun onDestroyView() {
         super.onDestroyView()
 
@@ -702,6 +729,9 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Activit
         browserHandlingScrollFeature?.stop()
         browserHandlingScrollFeature = null
 
+        // Holds the Activity, so it must not outlive the view it was created with.
+        pictureInPictureFeature = null
+
         GlobalComponents.onPullToRefreshEnabledChanged = null
         GlobalComponents.onScreenshotProtectionEnabledChanged = null
         val engineView = fragmentEngineView

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/HomePressDispatcher.kt

@@ -0,0 +1,47 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+package eu.weblibre.flutter_mozilla_components
+
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentActivity
+import mozilla.components.support.base.feature.UserInteractionHandler
+
+/**
+ * Dispatches "the user is leaving the app" to the browser fragments so they can enter
+ * picture-in-picture.
+ *
+ * Lives in this package because Mozilla Components is an `implementation` dependency, so
+ * [UserInteractionHandler] is not on the app module's compile classpath.
+ */
+object HomePressDispatcher {
+    /**
+     * Returns true if a fragment handled the home press (i.e. entered picture-in-picture),
+     * in which case the caller must not run the default `onUserLeaveHint` behaviour.
+     */
+    fun onUserLeaveHint(activity: FragmentActivity): Boolean {
+        // Runtime permission prompts trigger onUserLeaveHint too. That is not the user
+        // leaving, so it must not put a playing fullscreen video into picture-in-picture.
+        if (GlobalComponents.components?.notificationsDelegate?.isRequestingPermission == true) {
+            return false
+        }
+
+        return activity.supportFragmentManager.fragments.any(::dispatch)
+    }
+
+    private fun dispatch(fragment: Fragment): Boolean {
+        // A hidden or paused fragment must not be able to grab picture-in-picture.
+        if (!fragment.isResumed) {
+            return false
+        }
+
+        if (fragment is UserInteractionHandler && fragment.onHomePressed()) {
+            return true
+        }
+
+        return fragment.childFragmentManager.fragments.any(::dispatch)
+    }
+}

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/activities/ExternalAppBrowserActivity.kt

@@ -16,6 +16,7 @@ import androidx.core.view.WindowCompat
 import eu.weblibre.flutter_mozilla_components.ColorSchemePreference
 import eu.weblibre.flutter_mozilla_components.ExternalAppBrowserFragment
 import eu.weblibre.flutter_mozilla_components.GlobalComponents
+import eu.weblibre.flutter_mozilla_components.HomePressDispatcher
 import eu.weblibre.flutter_mozilla_components.PwaConstants
 import eu.weblibre.flutter_mozilla_components.PwaSessionCreator
 import eu.weblibre.flutter_mozilla_components.R
@@ -122,6 +123,14 @@ open class ExternalAppBrowserActivity : AppCompatActivity() {
         showFragment(sessionId)
     }
 
+    override fun onUserLeaveHint() {
+        if (HomePressDispatcher.onUserLeaveHint(this)) {
+            return
+        }
+
+        super.onUserLeaveHint()
+    }
+
     private fun waitForComponents(sessionId: String) {
         coroutineScope.launch {
             var elapsedMs = 0L
@@ -271,12 +280,4 @@ open class ExternalAppBrowserActivity : AppCompatActivity() {
         }
     }
 
-    override fun onPictureInPictureModeChanged(isInPictureInPictureMode: Boolean) {
-        super.onPictureInPictureModeChanged(isInPictureInPictureMode)
-        val fragment = supportFragmentManager.findFragmentById(R.id.container)
-        if (fragment is ExternalAppBrowserFragment) {
-            fragment.onPictureInPictureModeChanged(isInPictureInPictureMode)
-        }
-    }
-
 }