Fix memory leaks by clearing view bindings and references in fragments

app/src/main/java/fr/free/nrw/commons/bookmarks/BookmarkListRootFragment.java

@@ -258,6 +258,12 @@ public void onBackStackChanged() {
 
     }
 
+    @Override
+    public void onDestroyView() {
+        super.onDestroyView();
+        binding = null;
+    }
+
     @Override
     public void onDestroy() {
         super.onDestroy();

app/src/main/java/fr/free/nrw/commons/bookmarks/locations/BookmarkLocationsFragment.kt

@@ -143,6 +143,11 @@ class BookmarkLocationsFragment : DaggerFragment() {
         }
     }
 
+    override fun onDestroyView() {
+        super.onDestroyView()
+        binding = null
+    }
+
     override fun onDestroy() {
         super.onDestroy()
         // Make sure to null out the binding to avoid memory leaks

app/src/main/java/fr/free/nrw/commons/bookmarks/pictures/BookmarkPicturesFragment.java

@@ -67,6 +67,12 @@ public void onStop() {
         controller.stop();
     }
 
+    @Override
+    public void onDestroyView() {
+        super.onDestroyView();
+        binding = null;
+    }
+
     @Override
     public void onDestroy() {
         super.onDestroy();

app/src/main/java/fr/free/nrw/commons/contributions/ContributionsFragment.kt

@@ -685,14 +685,23 @@ class ContributionsFragment : CommonsDaggerSupportFragment(), FragmentManager.On
     override fun onDestroy() {
         try {
             compositeDisposable.clear()
+            // Remove child fragment safely
+            contributionsListFragment?.let {
+                childFragmentManager.beginTransaction()
+                    .remove(it)
+                    .commitAllowingStateLoss()
+            }
             childFragmentManager.removeOnBackStackChangedListener(this)
-            locationManager!!.unregisterLocationManager()
-            locationManager!!.removeLocationListener(this)
-            super.onDestroy()
+            locationManager?.unregisterLocationManager()
+            locationManager?.removeLocationListener(this)
+            // Nullify locationManager to prevent leaks
+            locationManager = null
         } catch (exception: IllegalArgumentException) {
             Timber.e(exception)
         } catch (exception: IllegalStateException) {
             Timber.e(exception)
+        } finally {
+            super.onDestroy()
         }
     }
 
@@ -757,7 +766,9 @@ class ContributionsFragment : CommonsDaggerSupportFragment(), FragmentManager.On
 
     override fun onDestroyView() {
         super.onDestroyView()
-        presenter!!.onDetachView()
+        presenter?.onDetachView()
+        binding = null
+        contributionsListFragment = null
     }
 
     override fun notifyDataSetChanged() {

app/src/main/java/fr/free/nrw/commons/contributions/MainActivity.kt

@@ -527,6 +527,11 @@ after opening the app.
         quizChecker!!.cleanup()
         locationManager!!.unregisterLocationManager()
         // Remove ourself from hashmap to prevent memory leaks
+        try {
+            locationManager?.unregisterLocationManager()
+        } catch (e: Exception) {
+            Timber.e(e, "Error while cleaning up locationManager")
+        }
         locationManager = null
         super.onDestroy()
     }

app/src/main/java/fr/free/nrw/commons/media/MediaDetailFragment.kt

@@ -190,8 +190,13 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
 
     private var initialListTop: Int = 0
 
+    /**
+     * Holds the view binding reference for this fragment.
+     * Use bindingOrNull for safe access after view destruction.
+     */
     private var _binding: FragmentMediaDetailBinding? = null
     private val binding get() = _binding!!
+    private val bindingOrNull get() = _binding
 
     private var descriptionHtmlCode: String? = null
 
@@ -340,25 +345,27 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
 
         handleBackEvent(view)
 
-        //set onCLick listeners
-        binding.mediaDetailLicense.setOnClickListener { onMediaDetailLicenceClicked() }
-        binding.mediaDetailCoordinates.setOnClickListener { onMediaDetailCoordinatesClicked() }
-        binding.sendThanks.setOnClickListener { sendThanksToAuthor() }
-        binding.dummyCaptionDescriptionContainer.setOnClickListener { showCaptionAndDescription() }
-        binding.mediaDetailImageView.setOnClickListener {
-            launchZoomActivity(
-                binding.mediaDetailImageView
-            )
+        /**
+         * Safely sets click listeners on media detail UI elements using bindingOrNull.
+         * Prevents potential crashes caused by view being destroyed during delayed callbacks.
+         */
+        bindingOrNull?.let { binding ->
+            binding.mediaDetailLicense.setOnClickListener { onMediaDetailLicenceClicked() }
+            binding.mediaDetailCoordinates.setOnClickListener { onMediaDetailCoordinatesClicked() }
+            binding.sendThanks.setOnClickListener { sendThanksToAuthor() }
+            binding.dummyCaptionDescriptionContainer.setOnClickListener { showCaptionAndDescription() }
+            binding.mediaDetailImageView.setOnClickListener {
+                launchZoomActivity(binding.mediaDetailImageView)
+            }
+            binding.categoryEditButton.setOnClickListener { onCategoryEditButtonClicked() }
+            binding.depictionsEditButton.setOnClickListener { onDepictionsEditButtonClicked() }
+            binding.seeMore.setOnClickListener { onSeeMoreClicked() }
+            binding.mediaDetailAuthor.setOnClickListener { onAuthorViewClicked() }
+            binding.nominateDeletion.setOnClickListener { onDeleteButtonClicked() }
+            binding.descriptionEdit.setOnClickListener { onDescriptionEditClicked() }
+            binding.coordinateEdit.setOnClickListener { onUpdateCoordinatesClicked() }
+            binding.copyWikicode.setOnClickListener { onCopyWikicodeClicked() }
         }
-        binding.categoryEditButton.setOnClickListener { onCategoryEditButtonClicked() }
-        binding.depictionsEditButton.setOnClickListener { onDepictionsEditButtonClicked() }
-        binding.seeMore.setOnClickListener { onSeeMoreClicked() }
-        binding.mediaDetailAuthor.setOnClickListener { onAuthorViewClicked() }
-        binding.nominateDeletion.setOnClickListener { onDeleteButtonClicked() }
-        binding.descriptionEdit.setOnClickListener { onDescriptionEditClicked() }
-        binding.coordinateEdit.setOnClickListener { onUpdateCoordinatesClicked() }
-        binding.copyWikicode.setOnClickListener { onCopyWikicodeClicked() }
-
         binding.fileUsagesComposeView.apply {
             setViewCompositionStrategy(ViewCompositionStrategy.DisposeOnViewTreeLifecycleDestroyed)
             setContent {
@@ -404,14 +411,19 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
         /**
          * Gets the height of the frame layout as soon as the view is ready and updates aspect ratio
          * of the picture.
+         * Updated to use bindingOrNull inside delayed callbacks to prevent crashes
+         * when view is destroyed before post/postDelayed is executed.
          */
-        view.post{
-            val width = binding.mediaDetailScrollView.width
+        view.post {
+            val safeBinding = bindingOrNull ?: return@post
+            val width = safeBinding.mediaDetailScrollView.width
             if (width > 0) {
-                frameLayoutHeight = binding.mediaDetailFrameLayout.measuredHeight
+                frameLayoutHeight = safeBinding.mediaDetailFrameLayout.measuredHeight
                 updateAspectRatio(width)
             } else {
-                view.postDelayed({ updateAspectRatio(binding.root.width) }, 1)
+                view.postDelayed({
+                    bindingOrNull?.let { updateAspectRatio(it.root.width) }
+                }, 1)
             }
         }
 
@@ -526,45 +538,56 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
             binding.sendThanks.visibility = View.VISIBLE
         }
 
-        binding.mediaDetailScrollView.viewTreeObserver.addOnGlobalLayoutListener(
+        /**
+         * Sets a one-time global layout listener to safely access view dimensions.
+         * Uses bindingOrNull to avoid crash if the fragment view is destroyed
+         * before the callback is executed.
+         */
+        bindingOrNull?.mediaDetailScrollView?.viewTreeObserver?.addOnGlobalLayoutListener(
             object : OnGlobalLayoutListener {
                 override fun onGlobalLayout() {
+                    val safeBinding = bindingOrNull ?: return
                     if (context == null) {
                         return
                     }
-                    binding.mediaDetailScrollView.viewTreeObserver.removeOnGlobalLayoutListener(
+                    safeBinding.mediaDetailScrollView.viewTreeObserver.removeOnGlobalLayoutListener(
                         this
                     )
-                    oldWidthOfImageView = binding.mediaDetailScrollView.width
-                    if (media != null) {
+                    oldWidthOfImageView = safeBinding.mediaDetailScrollView.width
+                    media?.filename?.let {
                         displayMediaDetails()
-                        fetchFileUsages(media?.filename!!)
+                        fetchFileUsages(it)
                     }
                 }
             }
         )
-        binding.progressBarEdit.visibility = View.GONE
+        bindingOrNull?.progressBarEdit?.visibility = View.GONE
     }
 
     override fun onConfigurationChanged(newConfig: Configuration) {
         super.onConfigurationChanged(newConfig)
-        binding.mediaDetailScrollView.viewTreeObserver.addOnGlobalLayoutListener(
+        /**
+         * Sets a global layout listener to update the aspect ratio when device configuration changes.
+         * Uses bindingOrNull to avoid crashes in case the view is destroyed before callback.
+         */
+        bindingOrNull?.mediaDetailScrollView?.viewTreeObserver?.addOnGlobalLayoutListener(
             object : OnGlobalLayoutListener {
                 override fun onGlobalLayout() {
+                    val safeBinding = bindingOrNull ?: return
                     /**
                      * We update the height of the frame layout as the configuration changes.
                      */
-                    binding.mediaDetailFrameLayout.post {
-                        frameLayoutHeight = binding.mediaDetailFrameLayout.measuredHeight
-                        updateAspectRatio(binding.mediaDetailScrollView.width)
+                    safeBinding.mediaDetailFrameLayout.post {
+                        frameLayoutHeight = safeBinding.mediaDetailFrameLayout.measuredHeight
+                        updateAspectRatio(safeBinding.mediaDetailScrollView.width)
                     }
-                    if (binding.mediaDetailScrollView.width != oldWidthOfImageView) {
+                    if (safeBinding.mediaDetailScrollView.width != oldWidthOfImageView) {
                         if (newWidthOfImageView == 0) {
-                            newWidthOfImageView = binding.mediaDetailScrollView.width
+                            newWidthOfImageView = safeBinding.mediaDetailScrollView.width
                             updateAspectRatio(newWidthOfImageView)
                         }
-                        binding.mediaDetailScrollView.viewTreeObserver.removeOnGlobalLayoutListener(
-                            this
+                        safeBinding.mediaDetailScrollView.viewTreeObserver.removeOnGlobalLayoutListener(
+                        this
                         )
                     }
                 }
@@ -613,7 +636,7 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
     }
 
     private fun onMediaRefreshed(media: Media) {
-        media.categories = this.media!!.categories
+        media.categories = this.media?.categories
         this.media = media
         setTextFields(media)
         compositeDisposable.addAll(
@@ -627,29 +650,30 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
     }
 
     private fun onDiscussionLoaded(discussion: String) {
-        binding.mediaDetailDisc.text = prettyDiscussion(discussion.trim { it <= ' ' })
+        bindingOrNull?.mediaDetailDisc?.text = prettyDiscussion(discussion.trim { it <= ' ' })
     }
 
     private fun onDeletionPageExists(deletionPageExists: Boolean) {
-        if (getUserName(requireContext()) == null && getUserName(requireContext()) != media!!.author) {
-            binding.nominateDeletion.visibility = View.GONE
-            binding.nominatedDeletionBanner.visibility = View.GONE
+        val safeBinding = bindingOrNull ?: return
+
+        if (getUserName(requireContext()) == null && getUserName(requireContext()) != media?.author) {
+            safeBinding.nominateDeletion.visibility = View.GONE
+            safeBinding.nominatedDeletionBanner.visibility = View.GONE
         } else if (deletionPageExists) {
             if (applicationKvStore.getBoolean(
-                    String.format(NOMINATING_FOR_DELETION_MEDIA, media!!.imageUrl), false
+                    String.format(NOMINATING_FOR_DELETION_MEDIA, media?.imageUrl), false
                 )
             ) {
                 applicationKvStore.remove(
-                    String.format(NOMINATING_FOR_DELETION_MEDIA, media!!.imageUrl)
+                    String.format(NOMINATING_FOR_DELETION_MEDIA, media?.imageUrl)
                 )
-                binding.progressBarDeletion.visibility = View.GONE
+                safeBinding.progressBarDeletion.visibility = View.GONE
             }
-            binding.nominateDeletion.visibility = View.GONE
-
-            binding.nominatedDeletionBanner.visibility = View.VISIBLE
+            safeBinding.nominateDeletion.visibility = View.GONE
+            safeBinding.nominatedDeletionBanner.visibility = View.VISIBLE
         } else if (!isCategoryImage) {
-            binding.nominateDeletion.visibility = View.VISIBLE
-            binding.nominatedDeletionBanner.visibility = View.GONE
+            safeBinding.nominateDeletion.visibility = View.VISIBLE
+            safeBinding.nominatedDeletionBanner.visibility = View.GONE
         }
     }
 
@@ -784,14 +808,18 @@ class MediaDetailFragment : CommonsDaggerSupportFragment(), CategoryEditHelper.C
         }
     }
 
+    /**
+     * Clears binding and removes layout listener to prevent memory leaks
+     * or crashes from delayed UI callbacks after the view is destroyed.
+     */
     override fun onDestroyView() {
-        if (layoutListener != null && view != null) {
-            requireView().viewTreeObserver.removeGlobalOnLayoutListener(layoutListener) // old Android was on crack. CRACK IS WHACK
+        layoutListener?.let {
+            view?.viewTreeObserver?.removeOnGlobalLayoutListener(it)
             layoutListener = null
         }
 
         compositeDisposable.clear()
-
+        _binding = null
         super.onDestroyView()
     }
 
@@ -2263,4 +2291,4 @@ fun FileUsagesContainer(
         }
 
     }
-}
+}

app/src/main/java/fr/free/nrw/commons/profile/ProfileActivity.kt

@@ -122,6 +122,10 @@ class ProfileActivity : BaseActivity() {
     public override fun onDestroy() {
         super.onDestroy()
         compositeDisposable.clear()
+        // Nullify fragment references to avoid memory leaks
+        if (::achievementsFragment.isInitialized) achievementsFragment.setHasOptionsMenu(false)
+        if (::leaderboardFragment.isInitialized) leaderboardFragment.setHasOptionsMenu(false)
+        contributionsFragment = null
     }
 
     override fun onCreateOptionsMenu(menu: Menu): Boolean {

app/src/main/java/fr/free/nrw/commons/upload/UploadActivity.kt

@@ -882,6 +882,8 @@ class UploadActivity : BaseActivity(), UploadContract.View, UploadBaseFragment.C
             uploadCategoriesFragment!!.callback = null
         }
         onBackPressedCallback.remove()
+        locationManager?.unregisterLocationManager()
+        UploadMediaPresenter.presenterCallback = null // Clearing reference
     }
 
     /**

app/src/main/res/values/strings.xml

@@ -381,8 +381,8 @@
   <string name="statistics_thanks">Thanks Received</string>
   <string name="statistics_featured">Featured Images</string>
   <string name="statistics_wikidata_edits">Images via \"Nearby Places\"</string>
-  <string name="level">Level %d</string>
-  <string name="profileLevel">%s (Level %s)</string>
+  <string name="level" formatted="false">Level %d</string>
+  <string name="profileLevel" formatted="false">%s (Level %s)</string>
   <string name="images_uploaded">Images Uploaded</string>
   <string name="image_reverts">Images Not Reverted</string>
   <string name="images_used_by_wiki">Images Used</string>