fix(slideshow) Use interface instead of EventBus

EventBus is considered deprecated by the maintainers and we want to get
rid of it eventually. So extending its usage is not the right approach.

Instead, a callback interface is defined. The pre-existing pattern of
looking up the enclosing activity via getTypedActivity() is used to find
the callback. Long-term, the getTypedActivity() might also be a pattern we
want to get rid of, but it would require a pretty thorough refactoring of
the FileDisplayActivity to make it work.

Signed-off-by: Philipp Hasper <vcs@hasper.info>

Author: PhilLab

app/src/main/java/com/owncloud/android/ui/activity/FileDisplayActivity.kt

@@ -121,7 +121,6 @@ import com.owncloud.android.ui.dialog.SendShareDialog.SendShareDialogDownloader
 import com.owncloud.android.ui.dialog.SortingOrderDialogFragment.OnSortingOrderListener
 import com.owncloud.android.ui.dialog.StoragePermissionDialogFragment
 import com.owncloud.android.ui.dialog.TermsOfServiceDialog
-import com.owncloud.android.ui.events.FilesRefreshEvent
 import com.owncloud.android.ui.events.SearchEvent
 import com.owncloud.android.ui.events.SyncEventFinished
 import com.owncloud.android.ui.events.TokenPushEvent
@@ -186,6 +185,7 @@ class FileDisplayActivity :
     OnEnforceableRefreshListener,
     OnSortingOrderListener,
     SendShareDialogDownloader,
+    FilesRefreshNeededListener,
     Injectable {
     private lateinit var binding: FilesBinding
 
@@ -1452,6 +1452,12 @@ class FileDisplayActivity :
     }
     // endregion
 
+    override fun onStop() {
+        Log_OC.v(TAG, "onStop()")
+        unregisterReceivers()
+        super.onStop()
+    }
+
     override fun onSortingOrderChosen(selection: FileSortOrder?) {
         val ocFileListFragment = this.listOfFilesFragment
         ocFileListFragment?.sortFiles(selection)
@@ -2760,11 +2766,6 @@ class FileDisplayActivity :
 
         registerReceivers()
 
-        // Register for the FilesRefreshEvent, only if not already registered
-        if (!EventBus.getDefault().isRegistered(this)) {
-            EventBus.getDefault().register(this)
-        }
-
         if (SettingsActivity.isBackPressed) {
             Log_OC.d(TAG, "User returned from settings activity, skipping reset content logic")
             return
@@ -2773,15 +2774,6 @@ class FileDisplayActivity :
         initFile()
     }
 
-    public override fun onStop() {
-        Log_OC.v(TAG, "onStop()")
-        if (EventBus.getDefault().isRegistered(this)) {
-            EventBus.getDefault().unregister(this)
-        }
-        unregisterReceivers()
-        super.onStop()
-    }
-
     private fun initFile() {
         val userOpt = user
         if (userOpt.isEmpty) {
@@ -3035,13 +3027,9 @@ class FileDisplayActivity :
         })
     }
 
-    // region EventBus
-    @Suppress("unused")
-    @Subscribe(threadMode = ThreadMode.MAIN)
-    fun onFilesRefreshNeeded(event: FilesRefreshEvent) {
+    override fun onFilesRefreshNeeded() {
         refreshCurrentDirectory()
     }
-    // endregion
 
     private fun handleEcosystemIntent(intent: Intent?) {
         ecosystemManager.receiveAccount(

app/src/main/java/com/owncloud/android/ui/activity/FilesRefreshNeededListener.kt

@@ -0,0 +1,12 @@
+/*
+ * Nextcloud - Android Client
+ *
+ * SPDX-FileCopyrightText: 2026 Your Name <your@email.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+package com.owncloud.android.ui.activity
+
+interface FilesRefreshNeededListener {
+    fun onFilesRefreshNeeded(): Unit
+}

app/src/main/java/com/owncloud/android/ui/dialog/RemoveFilesDialogFragment.kt

@@ -25,9 +25,8 @@ import com.owncloud.android.datamodel.FileDataStorageManager
 import com.owncloud.android.datamodel.OCFile
 import com.owncloud.android.ui.activity.FileActivity
 import com.owncloud.android.ui.activity.FileDisplayActivity
+import com.owncloud.android.ui.activity.FilesRefreshNeededListener
 import com.owncloud.android.ui.dialog.ConfirmationDialogFragment.ConfirmationDialogFragmentListener
-import com.owncloud.android.ui.events.FilesRefreshEvent
-import org.greenrobot.eventbus.EventBus
 import javax.inject.Inject
 
 /**
@@ -46,6 +45,7 @@ class RemoveFilesDialogFragment :
 
     @Inject
     lateinit var connectivityService: ConnectivityService
+
     private var positiveButton: MaterialButton? = null
 
     override fun onStart() {
@@ -102,6 +102,7 @@ class RemoveFilesDialogFragment :
 
         val fileActivity = getTypedActivity(FileActivity::class.java)
         val fda = getTypedActivity(FileDisplayActivity::class.java)
+        val filesRefreshNeededListener = getTypedActivity(FilesRefreshNeededListener::class.java)
         connectivityService.isNetworkAndServerAvailable { isAvailable ->
             if (isAvailable) {
                 fileActivity?.showLoadingDialog(fileActivity.getString(R.string.wait_a_moment))
@@ -115,7 +116,7 @@ class RemoveFilesDialogFragment :
                 }
 
                 if (offlineFiles.isNotEmpty()) {
-                    EventBus.getDefault().post(FilesRefreshEvent())
+                    filesRefreshNeededListener?.onFilesRefreshNeeded()
                 }
 
                 fileActivity?.dismissLoadingDialog()
@@ -127,7 +128,7 @@ class RemoveFilesDialogFragment :
                         fileDataStorageManager.addRemoveFileOfflineOperation(file)
                     }
                 }
-                EventBus.getDefault().post(FilesRefreshEvent())
+                filesRefreshNeededListener?.onFilesRefreshNeeded()
             }
 
             finishActionMode()

app/src/main/java/com/owncloud/android/ui/events/FilesRefreshEvent.kt

@@ -46,17 +46,14 @@ import com.owncloud.android.operations.RemoveFileOperation
 import com.owncloud.android.operations.SynchronizeFileOperation
 import com.owncloud.android.ui.activity.FileActivity
 import com.owncloud.android.ui.activity.FileDisplayActivity
-import com.owncloud.android.ui.events.FilesRefreshEvent
+import com.owncloud.android.ui.activity.FilesRefreshNeededListener
 import com.owncloud.android.ui.fragment.FileFragment
 import com.owncloud.android.ui.fragment.GalleryFragment
 import com.owncloud.android.ui.fragment.OCFileListFragment
 import com.owncloud.android.ui.preview.model.PreviewImageActivityState
 import com.owncloud.android.utils.DisplayUtils
 import com.owncloud.android.utils.MimeTypeUtil
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings
-import org.greenrobot.eventbus.EventBus
-import org.greenrobot.eventbus.Subscribe
-import org.greenrobot.eventbus.ThreadMode
 import java.io.Serializable
 import javax.inject.Inject
 import kotlin.math.max
@@ -70,6 +67,7 @@ class PreviewImageActivity :
     FileActivity(),
     FileFragment.ContainerActivity,
     OnRemoteOperationListener,
+    FilesRefreshNeededListener,
     Injectable {
     private var livePhotoFile: OCFile? = null
     private var viewPager: ViewPager2? = null
@@ -213,13 +211,9 @@ class PreviewImageActivity :
         }
     }
 
-    // region EventBus
-    @Suppress("unused")
-    @Subscribe(threadMode = ThreadMode.MAIN)
-    fun onFilesRefreshNeeded(event: FilesRefreshEvent) {
+    override fun onFilesRefreshNeeded() {
         initViewPager()
     }
-    // endregion
 
     fun initViewPager() {
         if (user.isPresent) {
@@ -273,11 +267,6 @@ class PreviewImageActivity :
         super.onStart()
         registerReceivers()
 
-        // Register for the FilesRefreshEvent, only if not already registered
-        if (!EventBus.getDefault().isRegistered(this)) {
-            EventBus.getDefault().register(this)
-        }
-
         val optionalUser = user
         if (optionalUser.isPresent) {
             var file: OCFile? = file ?: throw IllegalStateException("Instanced with a NULL OCFile")
@@ -418,10 +407,6 @@ class PreviewImageActivity :
             downloadFinishReceiver = null
         }
 
-        if (EventBus.getDefault().isRegistered(this)) {
-            EventBus.getDefault().unregister(this)
-        }
-
         super.onStop()
     }