BackupRestoreSettingsFragment: add UI options to import/export subscriptions

* create SubscriptionsImportExportHelper to share common code used in
  SubscriptionFragment and BackupRestoreSettingsFragment
* Add UI options for import/export in BackupRestoreSettingsFragment

app/src/main/java/org/schabi/newpipe/local/subscription/SubscriptionFragment.kt

@@ -1,6 +1,5 @@
 package org.schabi.newpipe.local.subscription
 
-import android.app.Activity
 import android.content.Context
 import android.content.DialogInterface
 import android.os.Bundle
@@ -14,8 +13,6 @@ import android.view.View
 import android.view.ViewGroup
 import android.webkit.MimeTypeMap
 import android.widget.Toast
-import androidx.activity.result.ActivityResult
-import androidx.activity.result.contract.ActivityResultContracts.StartActivityForResult
 import androidx.annotation.StringRes
 import androidx.appcompat.app.AlertDialog
 import androidx.lifecycle.ViewModelProvider
@@ -26,9 +23,6 @@ import com.xwray.groupie.GroupAdapter
 import com.xwray.groupie.Section
 import com.xwray.groupie.viewbinding.GroupieViewHolder
 import io.reactivex.rxjava3.disposables.CompositeDisposable
-import java.text.SimpleDateFormat
-import java.util.Date
-import java.util.Locale
 import org.schabi.newpipe.R
 import org.schabi.newpipe.database.feed.model.FeedGroupEntity.Companion.GROUP_ALL_ID
 import org.schabi.newpipe.databinding.DialogTitleBinding
@@ -52,10 +46,6 @@ import org.schabi.newpipe.local.subscription.item.FeedGroupCarouselItem
 import org.schabi.newpipe.local.subscription.item.GroupsHeader
 import org.schabi.newpipe.local.subscription.item.Header
 import org.schabi.newpipe.local.subscription.item.ImportSubscriptionsHintPlaceholderItem
-import org.schabi.newpipe.local.subscription.workers.SubscriptionExportWorker
-import org.schabi.newpipe.local.subscription.workers.SubscriptionImportInput
-import org.schabi.newpipe.streams.io.NoFileManagerSafeGuard
-import org.schabi.newpipe.streams.io.StoredFileHelper
 import org.schabi.newpipe.util.NavigationHelper
 import org.schabi.newpipe.util.OnClickGesture
 import org.schabi.newpipe.util.ServiceHelper
@@ -68,6 +58,7 @@ class SubscriptionFragment : BaseStateFragment<SubscriptionState>() {
 
     private lateinit var viewModel: SubscriptionViewModel
     private lateinit var subscriptionManager: SubscriptionManager
+    private lateinit var importExportHelper: SubscriptionsImportExportHelper
     private val disposables: CompositeDisposable = CompositeDisposable()
 
     private val groupAdapter = GroupAdapter<GroupieViewHolder<FeedItemCarouselBinding>>()
@@ -76,11 +67,6 @@ class SubscriptionFragment : BaseStateFragment<SubscriptionState>() {
     private lateinit var feedGroupsSortMenuItem: GroupsHeader
     private val subscriptionsSection = Section()
 
-    private val requestExportLauncher =
-        registerForActivityResult(StartActivityForResult(), this::requestExportResult)
-    private val requestImportLauncher =
-        registerForActivityResult(StartActivityForResult(), this::requestImportResult)
-
     @State
     @JvmField
     var itemsListState: Parcelable? = null
@@ -100,6 +86,7 @@ class SubscriptionFragment : BaseStateFragment<SubscriptionState>() {
     override fun onAttach(context: Context) {
         super.onAttach(context)
         subscriptionManager = SubscriptionManager(requireContext())
+        importExportHelper = SubscriptionsImportExportHelper(this)
     }
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
@@ -139,7 +126,7 @@ class SubscriptionFragment : BaseStateFragment<SubscriptionState>() {
         // -- Import --
         val importSubMenu = menu.addSubMenu(R.string.import_from)
 
-        addMenuItemToSubmenu(importSubMenu, R.string.previous_export) { onImportPreviousSelected() }
+        addMenuItemToSubmenu(importSubMenu, R.string.previous_export) { importExportHelper.onImportPreviousSelected() }
             .setIcon(R.drawable.ic_backup)
 
         for (service in ServiceList.all()) {
@@ -157,7 +144,7 @@ class SubscriptionFragment : BaseStateFragment<SubscriptionState>() {
         // -- Export --
         val exportSubMenu = menu.addSubMenu(R.string.export_to)
 
-        addMenuItemToSubmenu(exportSubMenu, R.string.file) { onExportSelected() }
+        addMenuItemToSubmenu(exportSubMenu, R.string.file) { importExportHelper.onExportSelected() }
             .setIcon(R.drawable.ic_save)
     }
 
@@ -193,48 +180,10 @@ class SubscriptionFragment : BaseStateFragment<SubscriptionState>() {
         NavigationHelper.openSubscriptionsImportFragment(fragmentManager, serviceId)
     }
 
-    private fun onImportPreviousSelected() {
-        NoFileManagerSafeGuard.launchSafe(
-            requestImportLauncher,
-            StoredFileHelper.getPicker(activity, JSON_MIME_TYPE),
-            TAG,
-            requireContext()
-        )
-    }
-
-    private fun onExportSelected() {
-        val date = SimpleDateFormat("yyyyMMddHHmm", Locale.ENGLISH).format(Date())
-        val exportName = "newpipe_subscriptions_$date.json"
-
-        NoFileManagerSafeGuard.launchSafe(
-            requestExportLauncher,
-            StoredFileHelper.getNewPicker(activity, exportName, JSON_MIME_TYPE, null),
-            TAG,
-            requireContext()
-        )
-    }
-
     private fun openReorderDialog() {
         FeedGroupReorderDialog().show(parentFragmentManager, null)
     }
 
-    private fun requestExportResult(result: ActivityResult) {
-        val data = result.data?.data
-        if (data != null && result.resultCode == Activity.RESULT_OK) {
-            SubscriptionExportWorker.schedule(activity, data)
-        }
-    }
-
-    private fun requestImportResult(result: ActivityResult) {
-        val data = result.data?.dataString
-        if (data != null && result.resultCode == Activity.RESULT_OK) {
-            ImportConfirmationDialog.show(
-                this,
-                SubscriptionImportInput.PreviousExportMode(data)
-            )
-        }
-    }
-
     // ////////////////////////////////////////////////////////////////////////
     // Fragment Views
     // ////////////////////////////////////////////////////////////////////////

app/src/main/java/org/schabi/newpipe/local/subscription/SubscriptionsImportExportHelper.kt

@@ -0,0 +1,82 @@
+package org.schabi.newpipe.local.subscription
+
+import android.app.Activity
+import android.content.Context
+import androidx.activity.result.ActivityResult
+import androidx.activity.result.contract.ActivityResultContracts.StartActivityForResult
+import androidx.fragment.app.Fragment
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+import org.schabi.newpipe.local.subscription.SubscriptionFragment.Companion.JSON_MIME_TYPE
+import org.schabi.newpipe.local.subscription.workers.SubscriptionExportWorker
+import org.schabi.newpipe.local.subscription.workers.SubscriptionImportInput
+import org.schabi.newpipe.streams.io.NoFileManagerSafeGuard
+import org.schabi.newpipe.streams.io.StoredFileHelper
+
+/**
+ * This class has to be created in onAttach() or onCreate().
+ *
+ * It contains registerForActivityResult calls and those
+ * calls are only allowed before a fragment/activity is created.
+ */
+class SubscriptionsImportExportHelper(
+    val fragment: Fragment
+) {
+    val context: Context = fragment.requireContext()
+
+    companion object {
+        val TAG: String =
+            SubscriptionsImportExportHelper::class.java.simpleName + "@" + Integer.toHexString(
+                hashCode()
+            )
+    }
+
+    private val requestExportLauncher =
+        fragment.registerForActivityResult(StartActivityForResult(), this::requestExportResult)
+    private val requestImportLauncher =
+        fragment.registerForActivityResult(StartActivityForResult(), this::requestImportResult)
+
+    private fun requestExportResult(result: ActivityResult) {
+        val data = result.data?.data
+        if (data != null && result.resultCode == Activity.RESULT_OK) {
+            SubscriptionExportWorker.schedule(context, data)
+        }
+    }
+
+    private fun requestImportResult(result: ActivityResult) {
+        val data = result.data?.dataString
+        if (data != null && result.resultCode == Activity.RESULT_OK) {
+            ImportConfirmationDialog.show(
+                fragment,
+                SubscriptionImportInput.PreviousExportMode(data)
+            )
+        }
+    }
+
+    fun onExportSelected() {
+        val date = SimpleDateFormat("yyyyMMddHHmm", Locale.ENGLISH).format(Date())
+        val exportName = "newpipe_subscriptions_$date.json"
+
+        NoFileManagerSafeGuard.launchSafe(
+            requestExportLauncher,
+            StoredFileHelper.getNewPicker(
+                context,
+                exportName,
+                JSON_MIME_TYPE,
+                null
+            ),
+            TAG,
+            context
+        )
+    }
+
+    fun onImportPreviousSelected() {
+        NoFileManagerSafeGuard.launchSafe(
+            requestImportLauncher,
+            StoredFileHelper.getPicker(context, JSON_MIME_TYPE),
+            TAG,
+            context
+        )
+    }
+}

app/src/main/java/org/schabi/newpipe/settings/BackupRestoreSettingsFragment.java

@@ -27,6 +27,7 @@ import org.schabi.newpipe.R;
 import org.schabi.newpipe.error.ErrorInfo;
 import org.schabi.newpipe.error.ErrorUtil;
 import org.schabi.newpipe.error.UserAction;
+import org.schabi.newpipe.local.subscription.SubscriptionsImportExportHelper;
 import org.schabi.newpipe.settings.export.BackupFileLocator;
 import org.schabi.newpipe.settings.export.ImportExportManager;
 import org.schabi.newpipe.streams.io.NoFileManagerSafeGuard;
@@ -57,8 +58,15 @@ public class BackupRestoreSettingsFragment extends BasePreferenceFragment {
     private final ActivityResultLauncher<Intent> requestExportPathLauncher =
             registerForActivityResult(new ActivityResultContracts.StartActivityForResult(),
                     this::requestExportPathResult);
+    private SubscriptionsImportExportHelper importExportHelper;
 
 
+    @Override
+    public void onAttach(@NonNull final Context context) {
+        super.onAttach(context);
+        importExportHelper = new SubscriptionsImportExportHelper(this);
+    }
+
     @Override
     public void onCreatePreferences(@Nullable final Bundle savedInstanceState,
                                     @Nullable final String rootKey) {
@@ -123,6 +131,21 @@ public class BackupRestoreSettingsFragment extends BasePreferenceFragment {
             alertDialog.show();
             return true;
         });
+
+        final Preference exportSubsPreference =
+                requirePreference(R.string.export_subscriptions_key);
+        exportSubsPreference.setOnPreferenceClickListener(reference -> {
+            importExportHelper.onExportSelected();
+            return true;
+        });
+
+        final Preference importSubsPreference =
+                requirePreference(R.string.import_subscriptions_key);
+        importSubsPreference.setOnPreferenceClickListener(preference -> {
+            importExportHelper.onImportPreviousSelected();
+            return true;
+        });
+
     }
 
     private void requestExportPathResult(final ActivityResult result) {

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

@@ -413,6 +413,8 @@
     <string name="import_export_data_path">import_export_data_path</string>
     <string name="import_data">import_data</string>
     <string name="export_data">export_data</string>
+    <string name="import_subscriptions_key">import_subscriptions_key</string>
+    <string name="export_subscriptions_key">export_subscriptions_key</string>
 
     <string name="clear_cookie_key">clear_cookie</string>
 

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

@@ -520,6 +520,11 @@
     <string name="export_ongoing">Exporting…</string>
     <string name="import_file_title">Import file</string>
     <string name="previous_export">Previous export</string>
+    <string name="import_subscriptions_title">Import subscriptions"</string>
+    <string name="export_subscriptions_title">Export subscriptions</string>
+    <string name="import_subscriptions_summary">Import subscriptions from a previous .json export"</string>
+    <string name="export_subscriptions_summary">Export your subscriptions to a .json file</string>
+    <string name="import_from_previous_export">Import from previous export</string>
     <string name="subscriptions_import_unsuccessful">Could not import subscriptions</string>
     <string name="subscriptions_export_unsuccessful">Could not export subscriptions</string>
     <string name="import_youtube_instructions">Import YouTube subscriptions from Google takeout:

app/src/main/res/xml/backup_restore_settings.xml

@@ -22,4 +22,18 @@
         android:summary="@string/reset_settings_summary"
         app:singleLineTitle="false"
         app:iconSpaceReserved="false" />
+
+    <Preference
+        android:key="@string/export_subscriptions_key"
+        android:title="@string/export_subscriptions_title"
+        android:summary="@string/export_subscriptions_summary"
+        app:singleLineTitle="false"
+        app:iconSpaceReserved="false" />
+
+    <Preference
+        android:key="@string/import_subscriptions_key"
+        android:title="@string/import_subscriptions_title"
+        android:summary="@string/import_subscriptions_summary"
+        app:singleLineTitle="false"
+        app:iconSpaceReserved="false" />
 </PreferenceScreen>